WO2023015461A1 - Base station, central station, and nonlinear signal processing method - Google Patents

Base station, central station, and nonlinear signal processing method Download PDF

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Publication number
WO2023015461A1
WO2023015461A1 PCT/CN2021/111907 CN2021111907W WO2023015461A1 WO 2023015461 A1 WO2023015461 A1 WO 2023015461A1 CN 2021111907 W CN2021111907 W CN 2021111907W WO 2023015461 A1 WO2023015461 A1 WO 2023015461A1
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signal
radio frequency
module
target
nonlinear
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PCT/CN2021/111907
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French (fr)
Chinese (zh)
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李建平
郭少南
胡克彬
黄丹
于香起
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华为技术有限公司
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Priority to PCT/CN2021/111907 priority Critical patent/WO2023015461A1/en
Priority to CN202180101438.7A priority patent/CN117941291A/en
Publication of WO2023015461A1 publication Critical patent/WO2023015461A1/en

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B10/00Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/25Arrangements specific to fibre transmission
    • H04B10/2507Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B10/00Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50Transmitters
    • H04B10/58Compensation for non-linear transmitter output

Definitions

  • the present application relates to the technical field of communication, and in particular to a base station, a central station and a nonlinear signal processing method.
  • nonlinear components on the wireless communication link in the wireless communication system such as low-noise amplifier, power amplifier (Power Amplifier, PA), photoelectric conversion (Optical-Electro, O/E) components, electro-optical conversion (Electro- Optical, E/O) components, etc.
  • These nonlinear components may cause nonlinear distortion of the signal on the communication link. Specifically, the output signal of the nonlinear component will appear in the output signal of a new frequency that is not in the input signal.
  • the component signal is a nonlinear distortion signal, which will interfere with the subsequent processing of some normal signals and affect the performance of the wireless communication system.
  • the nonlinear characteristics of the nonlinear components in the system can be corrected by analog predistortion to reduce the nonlinear distortion caused by the nonlinear components.
  • Analog predistortion refers to processing the signal input to the nonlinear components in advance, so that the signal change caused by the processing and the nonlinear distortion generated after the signal is input to the nonlinear components cancel each other, so that the nonlinear distortion caused by the nonlinear components Distortion is corrected.
  • the link for correcting the nonlinear index of nonlinear components is generally fixed, and the fitting ability of nonlinear distortion in the process of analog predistortion is limited, and can only be targeted to a certain extent Improve the characteristics of certain types of nonlinear components, so this method has a low ability to correct nonlinear distortion.
  • the application provides a base station, a central station, and a nonlinear signal processing method to improve the accuracy of calculating nonlinear distortion signals caused by nonlinear components, thereby further improving the correction of nonlinear distortion caused by nonlinear components or compensated performance.
  • the present application provides a base station, including: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2; each radio frequency link is used for Receive one signal of the corresponding frequency band through the antenna, and send the one signal to the optical module after performing radio frequency processing on the one signal;
  • the signal is subjected to electro-optical conversion processing to obtain an optical signal including the processed multi-channel signal;
  • the optical module includes nonlinear components, and there are a first radio frequency link and at least one radio frequency link among the plurality of radio frequency links
  • the second radio frequency link, the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal corresponds to the frequency band of the first radio frequency link
  • the optical signal also includes the nonlinear distortion signal; sending the optical signal to the central station, and performing photoelectric conversion processing on the optical signal to obtain an electrical signal
  • the base station can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component based on the signal that has previously passed through the nonlinear component and the nonlinear distortion signal caused by the nonlinear component, which can improve
  • the accuracy of the determined nonlinear distortion prediction signal can further predistort the signal transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the detection of the signal generated when the signal on the transmission link passes through nonlinear components
  • the correction of nonlinear distortion problem improves the accuracy of nonlinear distortion correction.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency
  • the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links
  • the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links
  • the second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component nonlinear distortion characteristics; calculate the target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameter The target prediction signal is corrected to obtain the nonlinear distortion prediction signal.
  • the base station calculates the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear components and the nonlinear distortion signal actually generated after the signal passes through the nonlinear components, which can improve the determination of nonlinear components.
  • the accuracy of the nonlinear distortion characteristics of the device is improved, thereby improving the accuracy of correcting the target prediction signal based on the nonlinear distortion characteristic parameters of the nonlinear components.
  • the iterative calculation module when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
  • the base station predicts the nonlinear distortion signal generated by the useful signal through the nonlinear components by using the useful signal and the distorted signal for modeling calculation, and can obtain the required calculation simply, quickly and accurately through the calculation model target prediction signal.
  • the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
  • the base station can further improve the accuracy of the determined nonlinear distortion prediction signal by correcting the predicted nonlinear distortion signal according to the nonlinear distortion characteristic parameters of the nonlinear components.
  • the optical module includes: an electro-optical conversion module, a photoelectric conversion module, a first port, a second port, and a third port; Conversion processing, the electro-optical conversion module includes the nonlinear components; the photoelectric conversion module is used to perform photoelectric conversion processing on the optical signal; the first port is used to receive the multi-channel signal; The second port is used to send the optical signal to the central station; the third port is used to send the electrical signal to the feature calculation module.
  • the electrical signal corresponding to the optical signal sent by the base station to the central station can be obtained, so that useful signals can be obtained from the electrical signal
  • the nonlinear distortion signal generated after passing through the nonlinear components of the optical module is fed back to the digital link of the base station, which is convenient for modeling and pre-distortion correction of nonlinear components.
  • the feature calculation module further includes a filtering module; the filtering module is configured to filter the electrical signal to obtain the target signal.
  • the base station performs filtering processing on the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and thus improve the accuracy of signal processing.
  • the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  • the base station can ensure that the non-linear distortion prediction signal determined according to the target signal and the at least one second radio frequency link signal have a time delay correction process on the target signal and at least one second radio frequency link signal are corresponding, so as to avoid errors caused by delay problems in the signal processing process.
  • the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module;
  • a signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator;
  • the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal;
  • the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed;
  • the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment
  • the base station can determine the time delay existing between the target signal and the signal of the at least one second radio frequency link through time delay calculation, and then calculate the time delay between the target signal and the at least one second radio frequency link according to the time delay
  • the time delay of the link signal is corrected, and at the same time, the timing update of the time delay calculation process is controlled by the lock number control method, which reduces a certain amount of signal processing.
  • the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
  • the threshold decision module of the base station controls the triggering of the lock module according to the magnitude of the correlation value of the nonlinear distortion signal and the correlation signal corresponding to the signal of at least one second radio frequency link, which can be based on the actual scene
  • the actual signal situation controls the update situation of the lock number to improve the accuracy of related control and scene adaptability.
  • the first radio frequency link when the first radio frequency link performs predistortion processing on the signal in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, it is specifically used to:
  • the nonlinear distortion prediction signal is subtracted from the signal in the frequency band corresponding to the radio frequency link to obtain a signal after predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link.
  • the present application provides a base station, including: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2; each radio frequency link is used for Receive one signal of the corresponding frequency band through the antenna, and send the one signal to the optical module after performing radio frequency processing on the one signal;
  • the signal is subjected to electro-optical conversion processing to obtain an optical signal including the processed multi-channel signal;
  • the optical module includes nonlinear components, and there are a first radio frequency link and at least one radio frequency link among the plurality of radio frequency links
  • the second radio frequency link, the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal corresponds to the frequency band of the first radio frequency link There is overlap, and the optical signal also includes the nonlinear distortion signal; sending the optical signal to the central station, receiving the target signal from the central station, and performing photoelectric
  • the base station sends the signal after passing through the nonlinear components to the central station, and then receives the signal containing the useful signal and the nonlinear distortion signal caused by the nonlinear component that is looped back by the central station, which can be based on the previous
  • the signal of the nonlinear component and the nonlinear distortion signal caused by the nonlinear component can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component, which can improve the accuracy of the determined nonlinear distortion prediction signal
  • the signal transmitted on the transmission link can be pre-distorted according to the determined nonlinear distortion prediction signal, so as to realize the correction of the nonlinear distortion problem generated when the signal on the transmission link passes through nonlinear components, and improve the performance of nonlinear distortion. Accuracy of linear distortion correction.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency
  • the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links
  • the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links
  • the second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component nonlinear distortion characteristics; calculate the target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameter The target prediction signal is corrected to obtain the nonlinear distortion prediction signal.
  • the iterative calculation module when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
  • the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
  • the feature calculation module further includes a filtering module; the filtering module is configured to filter the electrical signal to obtain the target signal.
  • the optical module when the optical module receives the target signal from the central station, performs photoelectric conversion processing on the target signal, and sends the processed target signal to the feature calculation module, Specifically used for: receiving a downlink signal from the central station, performing photoelectric conversion processing on the downlink signal, and sending the processed downlink signal to the feature calculation module, wherein the downlink signal includes the The target signal and other signals to be sent to the base station; when the feature calculation module receives the target signal from the optical module, it is specifically used to: receive the downlink signal from the optical module, and The downlink signal is filtered to obtain the target signal.
  • the base station can extract the target signal from the signal from the central station, which facilitates subsequent processing of the target signal, and avoids interference from other signals on the processing process of the target signal, thereby improving the accuracy of signal processing.
  • the target signal is looped back through the central station, so the nonlinear distortion problems of some related nonlinear components in the central station can also be corrected to a certain extent.
  • the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  • the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module;
  • a signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator;
  • the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal;
  • the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed;
  • the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment
  • the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
  • the first radio frequency link when the first radio frequency link performs predistortion processing on the signal in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, it is specifically used to:
  • the nonlinear distortion prediction signal is subtracted from the signal in the frequency band corresponding to the radio frequency link to obtain a signal after predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link.
  • the present application provides a central station, including: an optical module and a signal processing module; the optical module is used to perform photoelectric conversion processing on the optical signal to obtain an electrical signal after receiving an optical signal from a base station, and send the optical signal to the The signal processing module sends the electrical signal; wherein, the electrical signal includes nonlinear distortion signals, multiple signals received by the multiple radio frequency links of the base station through antennas, and the multiple radio frequency links of the multiple radio frequency links
  • the number is greater than or equal to 2, there are a first radio frequency link and at least one second radio frequency link in the plurality of radio frequency links, the base station contains nonlinear components, and the signal of the at least one second radio frequency link
  • the nonlinear distortion signal is generated after passing through the nonlinear components, and the frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link; the signal processing module is used to receive signals from the The electrical signal of the optical module, extracting the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal
  • the central station and the base station can form a loopback link, and the central station loops back the signal from the base station to the base station, so that the base station can correct the nonlinear distortion generated when the subsequent signal passes through the nonlinear components based on the actual signal
  • the signal is predicted and calculated, and the signal transmitted on the transmission link is pre-distorted according to the predicted nonlinear distortion signal, so as to improve the accuracy of the nonlinear distortion correction of the communication link between the base station and the central station. While correcting the nonlinear distortion problem in the base station, it can also correct some nonlinear distortion problems in the central station, and improve the accuracy of communication between the central station and the base station.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency
  • the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links
  • the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links
  • the second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the signal processing module includes a filtering module, and the filtering module is configured to receive the electrical signal from the optical module, filter the electrical signal, and obtain the target signal;
  • the optical module performs electro-optical conversion processing on the target signal, and sends the processed target signal to the base station, it is specifically used to: perform the target signal and other signals to be sent to the base station Electro-optical conversion processing, obtaining a downlink signal including the target signal and other signals to be sent to the base station, and sending the downlink signal to the base station.
  • the central station filters the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and improve the accuracy of signal processing.
  • the central station can send the target signal and other signals to the base station in one wave, which can make full use of the existing transmission link, avoid the overhead of adding an additional transmission link, and improve resource utilization.
  • the present application provides a central station, including: an optical module, a signal processing module, and a feature calculation module; the optical module is configured to receive an optical signal from at least one base station, and perform an operation on each of the at least one base station The optical signal of the base station is subjected to photoelectric conversion processing to obtain the electrical signal of each base station; wherein, the electrical signal of any base station includes a nonlinear distortion signal, and multiple signals received by multiple radio frequency links of the base station through the antenna, The number of the plurality of radio frequency links is greater than or equal to 2, there are a first radio frequency link and at least one second radio frequency link in the plurality of radio frequency links, the base station contains nonlinear components, and the at least A signal of a second radio frequency link passes through the nonlinear component to generate the nonlinear distortion signal, and the frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link; The electrical signals of the base stations are sent to the signal processing module and the feature calculation module; the feature calculation
  • the central station when the central station processes the signal from at least one base station, it can process the subsequent signal through the non-linear component based on the signal that has previously passed through the nonlinear component in the base station and the nonlinear distortion signal caused by the nonlinear component. Prediction and calculation of the nonlinear distortion signal generated by the linear components can improve the accuracy of the determined nonlinear distortion prediction signal, and furthermore, the signal transmitted from at least one base station can be more accurately calculated according to the determined nonlinear distortion prediction signal Distortion correction processing.
  • the central station can perform distortion correction processing on the signals from different base stations, and can effectively correct the nonlinear distortion problem of the base station and the central station.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency
  • the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links
  • the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links
  • the second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component The nonlinear distortion characteristic; calculate the target prediction signal according to at least one signal from the at least one second radio frequency link, wherein, the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameters to modify the target prediction signal to obtain the nonlinear distortion prediction signal.
  • the central station calculates the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear components and the nonlinear distortion signal actually generated after the signal passes through the nonlinear components, which can improve the determination of nonlinear
  • the accuracy of the nonlinear distortion characteristic of the component is improved, and then the accuracy of correcting the target prediction signal based on the nonlinear distortion characteristic parameter of the nonlinear component is improved.
  • the iterative calculation module when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
  • the central station predicts the nonlinear distortion signal generated by the useful signal through the nonlinear components by using the useful signal and the distorted signal for modeling calculation, and can obtain the required information easily, quickly and accurately through the calculation model. Calculated target prediction signal.
  • the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
  • the central station can further improve the accuracy of the determined nonlinear distortion prediction signal by correcting the predicted nonlinear distortion signal according to the nonlinear distortion characteristic parameters of the nonlinear components.
  • the feature calculation module further includes a filtering module; the filtering module is configured to filter the combined electrical signal to obtain the target signal.
  • the central station filters the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and improve the accuracy of signal processing.
  • the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  • the central station can ensure that the non-linear distortion prediction signal determined according to the target signal and the at least one second radio frequency link signal are within a time delay correction process for the target signal and at least one second radio frequency link signal.
  • the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module;
  • a signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator;
  • the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal;
  • the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed;
  • the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment
  • the central station can determine the time delay existing between the target signal and the signal of the at least one second radio frequency link through time delay calculation, and then calculate the time delay between the target signal and the at least one second radio frequency link according to the time delay.
  • the delay is corrected for the signal of the radio frequency link, and at the same time, the timing update of the delay calculation process is controlled by the lock number control method, which reduces a certain amount of signal processing.
  • the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
  • the threshold decision module of the central station controls the triggering of the lock module according to the magnitude of the correlation value of the nonlinear distortion signal and the correlation signal corresponding to the signal of at least one second radio frequency link, which can be based on the actual scene According to the actual signal situation, the update situation of the number of locks is controlled, and the accuracy of related control and scene adaptability are improved.
  • the at least one base station includes a first base station and a second base station
  • the signal processing module sequentially processes the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station.
  • the distortion correction processing it is specifically used to: perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal;
  • the nonlinear distortion prediction signal performs distortion correction processing on the first target combined signal to obtain a second target combined signal.
  • the signal processing module when the signal processing module performs distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal, specifically It is used for: subtracting the nonlinear distortion prediction signal corresponding to the first base station from the target combined signal to obtain the first target combined signal.
  • the present application provides a nonlinear signal processing method, which is applied to a base station or a central station.
  • the method includes: calculating target parameters according to the target signal, wherein the target signal includes: a first signal, at least one second signal is a nonlinear distortion signal generated after passing through a nonlinear component, the frequency band of the nonlinear distortion signal overlaps with the frequency band of the first signal, and the target parameter is used to characterize the nonlinear distortion signal Non-linear distortion characteristics of linear components; calculating a target prediction signal according to the at least one second signal, wherein the target prediction signal is a prediction signal of the nonlinear distortion signal; predicting the target according to the target parameter The signal is corrected to obtain a nonlinear distortion prediction signal; wherein, the nonlinear distortion prediction signal is a modified prediction signal of the nonlinear distortion signal.
  • calculating the target parameter according to the target signal includes: calculating the target parameter according to the set first calculation model and the target signal, wherein the first calculation model is used to represent the input non- Correspondence between one signal among the multiple signals of the linear component, the nonlinear distortion signal output by the nonlinear component with the same frequency band as the one signal, and the nonlinear distortion characteristic parameters of the nonlinear component relation.
  • calculating the target prediction signal according to the at least one second signal includes: calculating the target prediction signal according to a set second calculation model and the at least one second signal, wherein the The second calculation model is used to represent the corresponding relationship between at least one signal passing through the nonlinear component and the nonlinear distortion signal generated after the at least one signal passes through the nonlinear component.
  • correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal includes: multiplying the target parameter by the target prediction signal to obtain the Nonlinear distortion prediction signal.
  • the present application provides a device, the device includes a memory and a processor; the memory is used to store computer programs; the processor is used to execute the computer programs stored in the memory, to achieve the fifth aspect or Any possible design of the fifth aspect describes the method.
  • the present application provides a communication system, the communication system comprising: the base station described in the above first aspect or any possible design of the first aspect, or the above second aspect or any possible design of the second aspect
  • beneficial effects of the second aspect please refer to the description of the relevant beneficial effects of the above-mentioned first aspect, and for the above-mentioned beneficial effects of the fifth to seventh aspects, please refer to the description of the above-mentioned beneficial effects of the first to fourth aspects. Repeat it again.
  • FIG. 1 is a schematic diagram of the architecture of an ROF system
  • Fig. 2 is a schematic diagram of radio frequency signal transmission in an ROF system
  • Fig. 3 is the example diagram of three kinds of scenes that produce IMD2 in ROF system
  • Fig. 4a is a structural schematic diagram of an analog predistortion nonlinear correction link
  • Fig. 4b is a structural schematic diagram of a nonlinear distortion correction link based on a push-pull structure joint adaptive post-compensation
  • FIG. 5 is a schematic structural diagram of an ROF system provided in an embodiment of the present application.
  • FIG. 6 is a schematic diagram of a base station provided in an embodiment of the present application.
  • FIG. 7 is a schematic diagram of a feedback module in a base station provided by an embodiment of the present application.
  • FIG. 8 is a schematic diagram of an ROF system provided in an embodiment of the present application.
  • FIG. 9 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • FIG. 10 is a comparative schematic diagram of an optical module structure provided by an embodiment of the present application.
  • FIG. 11 is a simplified structural schematic diagram of a base station structure provided by an embodiment of the present application.
  • FIG. 12 is a schematic diagram of a base station and a central station provided in an embodiment of the present application.
  • FIG. 13 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • FIG. 14 is a schematic diagram of a central station provided by an embodiment of the present application.
  • FIG. 15 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • FIG. 16 is a schematic diagram of a nonlinear signal processing method provided by an embodiment of the present application.
  • Nonlinear distortion which means that the output signal of a component (or electronic component) does not have a linear relationship with the input signal, which is caused by the nonlinear characteristics of the component.
  • Nonlinear distortion is manifested as multiple signals of the same or different frequencies passing through nonlinear components (such as laser diodes, photodiodes, amplifiers, etc.), generating new harmonic components or interference signals of new frequency components.
  • Nonlinear distortion includes harmonic distortion (harmonic distortion, HD), intermodulation distortion (intermodulation distortion, IMD), and intermodulation distortion.
  • the intermodulation distortion is the distortion of the sum of the frequency components or the difference of the frequency components of an input signal introduced by the nonlinear components.
  • the nonlinear characteristics of the nonlinear components will cause the mutual (modulation) effect between the signals, and generate additional signals that are not in the original signal. This additional signal may affect the original signal. Some signals are causing interference.
  • the nonlinear components include, but are not limited to, an optoelectronic converter (electronic-optical converter, O-E), an electro-optical converter, an amplifier, and the like.
  • the photoelectric converter can be a photodiode (photo-diode, PD);
  • the electro-optical converter can be a laser diode (laser diode, LD), and the amplifier can be a low noise amplifier (low noise amplifier, LNA).
  • Pre-distortion means that before the signal passes through the nonlinear components, the signal is subjected to a preprocessing process whose characteristics are opposite to the nonlinear distortion characteristics caused by the nonlinear components, so that it is different from the non-linear distortion generated when the signal passes through the nonlinear components.
  • the linear distortion compensates each other, so as to reduce or avoid the nonlinear distortion caused by the nonlinear components.
  • At least one in the embodiments of the present application refers to one or more, and “multiple” refers to two or more.
  • “And/or” describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A, B can be singular or plural.
  • the character “/” generally indicates that the contextual objects are an “or” relationship.
  • At least one (item) of the following” or similar expressions refer to any combination of these items, including any combination of single item(s) or plural item(s).
  • At least one item (unit) of a, b or c can represent: a, b, c, a and b, a and c, b and c, or a, b and c, wherein a, b, c Can be single or multiple.
  • ROF is a wireless access technology that combines optical fiber communication and wireless communication.
  • the ROF system generally includes a center station (center station, CS) and a base station (base station, BS), which communicate through optical fibers.
  • the central station/base station can modulate the radio frequency electrical signal into an optical signal and then transmit the signal to the opposite end, and can realize the simultaneous ultra-wideband transmission of wireless carrier signals in multiple frequency bands by means of carrier multiplexing, which helps to reduce communication costs. System cost, power consumption and complexity etc.
  • ROF is widely used in mobile wireless communication systems, cable television (CATV) systems, and satellite communication systems.
  • Fig. 1 shows a schematic diagram of the architecture of an ROF system.
  • the ROF system may include a central station, a base station, and may also include user equipment.
  • the base station may also be called a head end, an analog head end, or a remote radio unit (remote radio unit, RRU).
  • the central station may also be called a mother end, an analog mother end, or a baseband unit (BBU).
  • the central station can modulate the radio frequency electrical signal (also called electromagnetic wave/microwave) to the laser, and then the modulated light wave can be transmitted to the base station through an optical fiber link
  • the base station receives the light wave signal from the central station, it demodulates the light wave signal through photoelectric conversion to obtain an electrical signal, and then transmits it to the user equipment through the antenna for use by the user equipment.
  • the communication downlink process is opposite to the above communication uplink process, and will not be repeated here.
  • the optical carrier link such as optical fiber or optical hybrid cable is used as the transmission link between the central station and the base station, and the optical carrier can be directly used to transmit radio frequency signals, thereby reducing signal transmission loss.
  • the above-mentioned optical link only plays the role of signal transmission, and the processing of signal exchange, control and signal regeneration can be concentrated in the central station, and the base station can realize the optical-electrical format conversion of the signal, so that complex and high-level The cost devices are concentrated in the central station, so that multiple base stations can share the resources of the central station, thereby reducing the power consumption and cost of the base station.
  • ROF system uses optical transmission technology for signal transmission, which has lower transmission loss than electrical transmission technology (usually the fiber attenuation is less than 0.4dB/km); ROF system supports ultra- Broadband signal bearing and transmission capability (transmission frequency can reach 0-40GHz); ROF system is easy to install and maintain (the weight of optical fiber is about one tenth of that of coaxial cable, and the cost of optical fiber is low), and ROF system has strong confidentiality (transmission The signal is carried by optical fiber, which can resist electromagnetic interference and enhance safety and confidentiality).
  • the ROF system also has some disadvantages.
  • the ROF system is an analog transmission system, so it is prone to signal impairments (such as noise and distortion); nonlinear effects such as dispersion may occur in optical links; electrical–optical (electrical–optical, E-O) and optical-electrical (O-E) conversion increase the complexity of processing and increase the deployment cost of the ROF system; some nonlinear components in the ROF system will cause nonlinear distortion of the signal and reduce the performance of the ROF system .
  • FIG. 2 is a schematic diagram of radio frequency (radio frequency, RF) signal transmission in an ROF system.
  • some nonlinear components such as laser diodes, photodiodes, radio frequency amplifiers, etc. can be used to implement functions such as signal processing and transmission.
  • these nonlinear components may cause nonlinear distortion of the signal during signal processing and transmission, affecting the accurate processing of the signal, especially in the case of multiple users, which will seriously reduce the performance of the ROF system.
  • IMD2 second-order intermodulation distortion
  • Fig. 3 is an example diagram of three scenarios in which IMD2 is generated in the ROF system.
  • IMD2 is the distortion of the sum of signal frequency components in two frequency bands passing through the nonlinear component.
  • the center frequency of the signal S F1 is F1
  • the signal frequency range of the signal S F1 is the frequency band F11-F12
  • the center frequency of the signal S F2 is F2
  • the signal frequency range of the signal S F2 is the frequency band F21-F22
  • the signal S F1 and The IMD2 signal may be generated after the signal S F2 passes through the nonlinear components at the same time.
  • the frequency range of the IMD2 signal is between (F11+F21) ⁇ (F12+F22).
  • the IMD2 signal generated after the signal S F1 and the signal S F2 pass through the nonlinear components will hit the signal S F3 , causing damage to the signal S F3 Interference affects subsequent normal processing of the signal S F3 .
  • IMD2 is the distortion of the difference between the signal frequency components of the two frequency bands passing through the nonlinear component.
  • the frequency range of the IMD2 signal generated by the above-mentioned signal S F1 and the signal S F2 passing through the nonlinear components at the same time is between (F11-F21) ⁇ (F12-F22), and the frequency band of the IMD2 signal is the same as that of the above-mentioned signal S F3
  • the frequency bands overlap they will also hit the signal S F3 , causing interference to the signal S F3 and affecting subsequent normal processing of the signal S F3 .
  • IMD2 is the distortion of the sum of frequency components of signals in a frequency band passing through nonlinear components.
  • the frequency range of the IMD2 signal generated by the signal S F1 after passing through the nonlinear components is the frequency range 2F11-2F12, and the frequency range of the IMD2 signal is the same as the above-mentioned signal S
  • the frequency bands of F3 overlap, they will also hit the signal S F3 , causing interference to the signal S F3 and affecting subsequent normal processing of the signal S F3 .
  • the second-order intermodulation distortion signals in the above three scenarios will affect the normal processing of useful signals, thereby affecting the performance of the ROF system.
  • one solution is to correct the nonlinear distortion in the ROF system through analog pre-distortion, and another solution is to combine the push-pull structure with the automatic The post-adaptive compensation method corrects the nonlinear distortion in the ROF system.
  • Fig. 4a is a schematic structural diagram of an analog predistortion nonlinear correction link.
  • the analog predistortion correction link can be built by using pre-designed analog components with fixed parameters and component characteristics to realize the analog predistortion function, which can improve some nonlinear distortion problems to a certain extent.
  • the pre-distortion correction link since the pre-distortion correction link is generally fixed, it can only correct the nonlinear distortion caused by certain types of nonlinear components in a targeted manner, and cannot achieve self-adaptation for the nonlinear distortion caused by different nonlinear components. Iterative correction processing, the scope of use is relatively limited. At the same time, the fitting capability of the fixed analog pre-distortion correction link to the nonlinear distortion signal is relatively limited, resulting in limited correction performance of the analog pre-distortion correction link. In addition, the analog predistortion correction chain cannot adaptively fit the nonlinear effects caused by temperature changes.
  • Fig. 4b is a schematic structural diagram of a nonlinear distortion correction link based on a push-pull structure combined with adaptive post-compensation.
  • the phase difference between the uplink and downlink in the system is maintained at around 180 degrees through the push-pull structure , the receiver uses balanced detection to suppress all even-order nonlinear distortions, and then uses an adaptive compensation algorithm to suppress the main odd-order nonlinear distortions.
  • the scheme can adaptively suppress the even-order distortion (such as second-order intermodulation distortion IMD2 and second-order harmonic distortion HD2) and odd-order distortion (such as third-order intermodulation distortion) generated by the nonlinearity of nonlinear components in the system simultaneously.
  • IMD3, XMD3, etc. two sets of LDs and PDs in the correction link of this solution need to be deployed, which has the problems of high system deployment cost and large deployment area of components.
  • an embodiment of the present application provides a base station, a central station, and a nonlinear signal processing method to implement the deployment of a nonlinear distortion correction system at a lower deployment cost, and at the same time improve the accuracy of calculating the nonlinear distortion signal, thereby The performance of correcting or compensating the nonlinear distortion according to the determined nonlinear distortion signal is further improved.
  • the base station, the central station and the nonlinear signal processing method provided in the embodiments of the present application are introduced in detail.
  • the base station, central station and nonlinear signal processing method provided in the embodiments of the present application are not limited to be applied to the ROF system, and can also be applied to the ROF-based analog optical wireless communication network architecture, similar central stations and distributed base station unit groups
  • network architectures such as the communication network architecture of the network, the communication network architecture in which multiple analog heads connect to a small number of central stations through optical transmission media (such as optical fiber or optical hybrid cable) (such as the network architecture in which multiple analog heads connect to a central station), etc. .
  • the base station, the central station, and the nonlinear signal processing method provided in the embodiments of the present application can also be applied to various other wireless communication systems, so as to solve the problem of nonlinear distortion caused by nonlinear components in the wireless communication system.
  • the wireless communication system may be, for example, a long term evolution (long term evolution, LTE) system, a 2G, 3G, 4G, 5G communication system, or a next generation communication system (such as a 6G system).
  • the base station, central station, and nonlinear signal processing method provided in the embodiments of the present application are not limited to solving the second-order intermodulation distortion problem, and can also solve harmonic distortion (such as HD2), intermodulation distortion (such as IMD3) and other nonlinear distortion problems.
  • FIG. 5 is a schematic structural diagram of an ROF system provided by an embodiment of the present application.
  • the ROF system adopts a digital-analog hybrid architecture.
  • the base station is mainly composed of optical modules, digital links, analog links and other parts. These parts constitute the downlink transmit (transport, TX) link and uplink receive (receive, RX) link in the base station.
  • the base station can send the signal from the user equipment to the central station through the uplink receive link, or through the downlink
  • the transmit link sends the signal from the central station to the user equipment.
  • the optical module is mainly used to convert the radio frequency electrical signal into an optical signal and then send it to the central station, or receive the optical signal from the central station and convert it into a radio frequency electrical signal.
  • the digital link part can be realized by way of field programmable gate array (field programmable gate array, FPGA) or application specific integrated circuit (application specific integrated circuit, ASIC) or digital signal processing (digital signal processor, DSP) circuit.
  • the digital link part can realize functions such as digital filtering, channel selection, and digital processing.
  • the analog link part includes at least components or modules such as amplifiers (such as power amplifiers (PA), LNA, etc.), and the analog link can be used for preliminary processing of the signal received by the base station and transmits the signal to the digital link. way for further processing.
  • PA power amplifiers
  • LNA low noise amplifier
  • the central station mainly includes optical modules, signal processing modules, etc.
  • the optical module is mainly used to convert the radio frequency electrical signal into an optical signal and then send it to the base station, or receive the optical signal from the base station and convert it into a radio frequency electrical signal.
  • the signal processing module is mainly used to implement conversion processing among baseband (baseband, BB) signals, intermediate frequency (intermediate frequency, IF) signals, and radio frequency (radio frequency) signals.
  • the base station and the central station may be connected through an optical transmission medium, wherein the optical transmission medium may be an optical fiber, a photoelectric hybrid cable, or the like.
  • the base station is a head-end architecture with a digital-analog hybrid design.
  • the base station has greater flexibility in function design and has unique advantages in performance, especially for non-standard systems.
  • the problem of linear correction will be described in detail below in conjunction with specific embodiments.
  • FIG. 6 is a schematic diagram of a base station provided by an embodiment of the present application.
  • the base station may include multiple radio frequency links (such as radio frequency link 1, radio frequency link 2, and radio frequency link 3 shown in FIG. 6), optical modules, and feature A computing module; wherein, the number of the plurality of radio frequency links is greater than or equal to two.
  • each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and transmit the one signal to the optical module after performing radio frequency processing on the one signal.
  • any one or more signals may be signals from one user equipment, and signals of different channels may be signals from different user equipments.
  • the optical module is configured to perform electro-optical conversion processing on the multi-channel signals from the plurality of radio frequency links to obtain an optical signal including the processed multi-channel signals, and send the optical signal to the central station, and Performing photoelectric conversion processing on the optical signal to obtain an electrical signal and sending the electrical signal to the feature calculation module; wherein, there are a first radio frequency link and at least one second radio frequency link among the plurality of radio frequency links , the optical module includes a nonlinear component, and the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal is the same as that of the first The frequency bands corresponding to the radio frequency links overlap; the optical signal includes the nonlinear distortion signal and the multichannel signal.
  • the base station further includes a combiner module (not shown in FIG. 6 ), the combiner module is configured to receive multiple signals from the multiple radio frequency links, and combine the multiple signals Perform combination processing to obtain a combination signal, and send the combination signal to the optical module.
  • the optical module is used to receive the combined signal from the combined module, and perform electro-optical conversion processing on the combined signal to obtain the optical signal.
  • the combining module may be a combiner.
  • Each second radio frequency link is further configured to perform radio frequency processing on a received signal of a corresponding frequency band, and then send the obtained signal to the feature calculation module.
  • the feature calculation module is configured to extract a target signal from the electrical signal from the optical module, wherein the target signal is a signal of a frequency band corresponding to the first radio frequency link included in the electrical signal ; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and send the nonlinear distortion prediction signal to the first radio frequency link, wherein the The nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
  • the first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
  • the radio frequency processing performed by the radio frequency link may include one or more of filtering, power or energy amplification, frequency conversion, analog-to-digital conversion, transmission rate adjustment, power adjustment, and digital-to-analog conversion.
  • the frequency band corresponding to the first radio frequency link overlaps with the frequency band of the nonlinear distortion signal, the starting frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the The cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency.
  • the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link
  • the second frequency is twice the cutoff frequency of the frequency band corresponding to the one second radio frequency link; for example, the scenario 3 shown in FIG. 3 .
  • the first frequency is the sum of the starting frequencies of the corresponding frequency bands of the two second radio frequency links
  • the second frequency is the sum of the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links, for example, the case of scenario 1 as shown in FIG. 3 ; or, the first frequency is the sum of the two second radio frequency links
  • the difference between the start frequencies of the frequency bands corresponding to the two radio frequency links, and the second frequency is the difference between the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links, for example, the scenario 2 shown in FIG. 3 .
  • the first radio frequency link when there is a second radio frequency link among the plurality of radio frequency links, the first radio frequency link may be the radio frequency link 3 shown in FIG. 6 , and the second radio frequency link may be It is radio frequency link 1 or radio frequency link 2 shown in FIG.
  • the frequency band of the linear distortion signal overlaps with the frequency band of the signal on the radio frequency link 3 .
  • the first radio frequency link may be the radio frequency chain 3 shown in FIG. 6, and the two second radio frequency links may be respectively shown in FIG.
  • the radio frequency link 1 and the radio frequency link 2 shown in 6 the signals on the radio frequency link 1 and the radio frequency link 2 generate a nonlinear distortion signal after passing through the nonlinear components, and the nonlinear distortion
  • the frequency band of the signal overlaps with the frequency band of the signal on the radio frequency link 3 .
  • the optical module may include an electro-optic conversion module, a photoelectric conversion module, a first port, a second port, and a third port.
  • the first port is used to receive the multiple signals from the multiple radio frequency links and transmit them to the electro-optic conversion module.
  • the electro-optic conversion module is connected to the first port, and is used to perform electro-optical conversion processing on the multi-channel signal to obtain an optical signal
  • the electro-optic conversion module includes the nonlinear component, and the nonlinear component It can be used for electrical-optical conversion processing of signals.
  • the nonlinear component is an electro-optical converter, such as an LD.
  • the first port is connected to the combining module, and the first port is used to receive the combining module from the combining module. signal and transmit it to the electro-optical conversion module.
  • the electro-optical conversion module is used to perform electro-optical conversion processing on the combined signal to obtain the optical signal.
  • the second port is connected to the electro-optical conversion module, and is used to send the optical signal obtained by the electro-optical conversion module, for example, to send the optical signal to a central station through an optical transmission medium.
  • the photoelectric conversion module is configured to receive the optical signal from the electro-optical conversion module, and perform photoelectric conversion processing on the optical signal to obtain the electrical signal.
  • the photoelectric conversion module is a photoelectric converter, such as a PD.
  • the optical signal received by the photoelectric conversion module from the electro-optic conversion module may be obtained by sampling an optical signal obtained by performing electro-optic conversion processing by the electro-optic conversion module.
  • the third port is connected to the photoelectric conversion module, and is used to send the electrical signal obtained by the photoelectric conversion module to the feature calculation module.
  • the feature calculation module includes a filter module and an iterative calculation module.
  • the filtering module is configured to receive the electrical signal sent by the photoelectric conversion module through the third port, and filter the electrical signal to obtain the target signal.
  • the filtering module is a filter.
  • the filtering module when it performs filtering processing on the electrical signal, it may use the signal frequency band of the first radio frequency link as a reference to perform filtering, so as to filter out the electrical signal that is related to the electrical signal.
  • the feature calculation module may further include a power amplification module, which is connected after the filter and used to amplify the power or energy of the target signal obtained by the filter.
  • the power amplification module may be an LNA.
  • the iterative calculation module can be used to: receive the target signal from the filter, and receive at least one signal from the at least one second radio frequency link, and according to the target signal calculating a target parameter, calculating a target prediction signal according to at least one signal of the at least one second radio frequency link, and then correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal.
  • the target parameter is used to characterize the nonlinear distortion characteristic of the nonlinear component
  • the target prediction signal is the second prediction signal of the nonlinear distortion signal.
  • the iterative calculation module calculates the target parameter according to the set first calculation model and the target signal, and calculates the target parameter according to the set second calculation model and the at least one first calculation model.
  • Calculate the target prediction signal for at least one signal of two radio frequency links wherein the first calculation model is used to represent one of the multiple signals input to the nonlinear component, and the output of the nonlinear component.
  • the second calculation model is used to represent the relationship between at least one signal passing through the nonlinear component and Correspondence between the nonlinear distortion signals generated after the at least one signal passes through the nonlinear components.
  • the above set first calculation model and the set second calculation model can be obtained by performing model training in advance.
  • the target parameter is multiplied by the target prediction signal to obtain the nonlinear distortion prediction signal.
  • the target parameter is a nonlinear distortion coefficient obtained according to at least one signal actually passing through the nonlinear component and the nonlinear distortion signal actually generated after the at least one signal passes through the nonlinear component, which can more accurately reflect Nonlinear distortion characteristics of nonlinear components.
  • the target prediction signal is obtained only by predicting a nonlinear distortion signal generated after the at least one signal passes through a nonlinear component based on at least one signal of the at least one second radio frequency link.
  • the corresponding target parameters are further used to correct the estimated nonlinear distortion prediction signal, and a more accurate nonlinear distortion prediction signal (that is, the second prediction signal) can be obtained.
  • the first prediction signal so as to greatly improve the accuracy of pre-distortion processing on the signal of the first radio frequency link according to the finally obtained nonlinear distortion prediction signal.
  • the feature calculation module further includes a feedback module, and the feedback module can be used to perform delay correction on signals received by the radio frequency link in the base station.
  • the feedback module may be located between the iterative calculation module and the filter, and the feedback module is used to receive the target signal from the filter and at least one channel from the at least one second radio frequency link signal, and perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link to obtain the target signal and at least one signal of the at least one second radio frequency link with consistent delays signal, and send the obtained signal to the iterative calculation module.
  • the feedback module may include a lock module, a correlator, a threshold decision module, a delay calculation module, and a delay alignment module.
  • the locking module is configured to respectively latch signals with a set time slot length from the at least one second radio frequency link, and send the latched signals to the correlator.
  • the number lock module can be realized by a latch.
  • the number lock module can use a fixed time slot lock number, for example, the number lock module can be based on a wireless communication frame structure, with a set duration (such as 10ms) synchronization signal as a reference, a fixed delay Collecting and respectively latching signals from the at least one second radio frequency link, wherein different delays correspond to signals of different time slots. For example, when the fixed delay is 5 ms, after the lock module collects signals with a total time length of 10 ms between the 10th and 20 ms, in the next collection, it collects signals with a total time length of 10 ms between the 15th and 25 ms .
  • a set duration such as 10ms
  • a fixed delay Collecting and respectively latching signals from the at least one second radio frequency link, wherein different delays correspond to signals of different time slots. For example, when the fixed delay is 5 ms, after the lock module collects signals with a total time length of 10 ms between the 10th and 20 ms, in the next collection, it
  • the lock module may perform signal acquisition and latch according to the control of the threshold judgment module, which will be described in detail below.
  • the correlator is configured to perform correlation processing on the target signal and the signal from the lock module to obtain a correlation signal, and send the correlation signal to the threshold judgment module, wherein the correlation signal is Nonlinear component signal.
  • the correlator when the correlator performs correlation processing on the target signal and the signal from the number-locking module, firstly, according to the signal from the number-locking module, that is, at least one channel of the at least one second radio frequency link signal to determine the target prediction signal, and then perform correlation processing on the target signal and the target prediction signal to obtain the correlation signal.
  • the correlator may determine the target prediction signal in the same manner as the iterative calculation module.
  • the threshold judgment module is configured to receive the correlation signal from the correlator, and judge whether the correlation value (or accumulation value or correlation accumulation value) of the received correlation signal is greater than or equal to a set value, and if so, Then send the related signal to the delay calculation module, otherwise, do not process the related signal.
  • the threshold decision module may also be used to perform latch control on the lock module. Specifically, when the threshold determination module determines that the correlation value of the correlation signal is greater than or equal to the set value, it instructs the lock module to start latching or perform latch update, and respectively latches signals from the at least one
  • the second radio frequency link sets the signal of the time slot length, and replaces the previously latched signal with the currently latched signal.
  • the set time slot length can be flexibly set according to actual needs.
  • the threshold judgment module determines that the correlation value of the correlation signal is less than the set value, instruct the lock module to suspend the latch signal, that is, stop latching the settings from the at least one second radio frequency link time slot length until the threshold judgment module again determines that the correlation value of the correlation signal from the correlator is greater than the set threshold, then the threshold judgment module instructs the lock module to continue latching the signal and updating the lock stored signal.
  • the delay calculation module is configured to calculate the signal of the first radio frequency link and the at least one second radio frequency link according to the correlation signal when receiving the correlation signal from the threshold judgment module The time delay between the signals of the set time slot length, and send the time delay to the time delay alignment module.
  • the delay alignment module is configured to, after receiving the delay from the delay calculation module, remove the setting between the target signal and the at least one second radio frequency link according to the delay. Signals with the time delay in the signals with a fixed slot length, and respectively removing the signals with the time delay with the target signal in the signals with the set time slot length of each second radio frequency link, thereby respectively retaining The target signal is a signal with the same time delay as the signal of the at least one second radio frequency link.
  • the above iterative calculation module calculates the nonlinear distortion prediction signal, it sends the nonlinear distortion prediction signal to the first radio frequency link, and the first radio frequency link receives the nonlinear distortion prediction signal, according to
  • the nonlinear distortion prediction signal performs pre-distortion processing on signals in a frequency band corresponding to the first radio frequency link. Specifically, after the first radio frequency link subtracts the nonlinear distortion prediction signal from the signal in the frequency band corresponding to the first radio frequency link, the predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link. after the signal.
  • the first radio frequency link performs radio frequency processing on the predistorted signal, and then sends it to the optical module, and the optical module can send the signal to the central station.
  • the first radio frequency link includes a pre-distortion processing module
  • the pre-distortion processing module is configured to perform pre-distortion processing on a signal in a frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal .
  • the pre-distortion processing module may be an adder, a multiplier, or a multiplication-add combination module, wherein the multiplication-add combination module has functions of a multiplier and an adder.
  • the base station can calculate the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear component and the nonlinear distortion signal actually generated after the signal passes through the nonlinear component, which can improve the determination of nonlinear The accuracy of the nonlinear distortion characteristics of a component.
  • the base station After the base station determines the nonlinear distortion parameter of the nonlinear component, it combines the parameter with the signal currently transmitted on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear component, which can improve the determined nonlinear
  • the accuracy of the distortion prediction signal can further pre-distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components
  • the correction of the problem can improve the accuracy of nonlinear distortion correction.
  • the method has a wide range of applications, and can more accurately predict the nonlinear distortion signals caused by various nonlinear components, and is also convenient for various nonlinear distortion signals.
  • the nonlinear distortion problem caused by linear components is corrected, so the method has strong versatility and adaptability.
  • the base station provided in the foregoing embodiments of the present application will be described below in combination with specific application scenarios and by taking two second radio frequency links among the plurality of radio frequency links as an example.
  • Fig. 8 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • the base station provided by the embodiment of the present application can be applied in a ROF system, and the base station includes at least three radio frequency links, which are respectively the first radio frequency link and the two second radio frequency links link.
  • the three radio frequency links can respectively receive signals of three different frequency bands through the antenna.
  • the second signal and the third signal are denoted as f2 and f3 respectively.
  • the base station shown in Figure 6 When the base station shown in Figure 6 is applied to the ROF system, the base station may also include some components or modules in the ROF system shown in Figure 5 above, as well as other components or modules for signal processing, the following example illustrate.
  • Each radio frequency link in the base station includes a digital link and an analog link.
  • the digital link may be implemented as a DSP shown in FIG. 8
  • the analog link may be implemented as an LNA shown in FIG. 8 .
  • LNA can be used as a high frequency or intermediate frequency preamplifier or amplifying circuit, which can amplify the power or energy of the signal, and has the advantages of low noise and high gain.
  • each radio frequency link in the base station may further include a filter, an adder, a data processing module, and the like.
  • the filter can be used to perform filtering processing on the signal, and keep or filter out the signal of a specific frequency band (or frequency).
  • the adder may be used to subtract the nonlinear distortion prediction signal from the signal in the frequency band corresponding to the first radio frequency link, so as to implement pre-distortion processing on the signal in the frequency band corresponding to the first radio frequency link.
  • the data processing module can be used to adjust the transmission rate, gain and other characteristics of the signal on the radio frequency link.
  • other components or modules may also be included in the radio frequency link. As for which components or modules are specifically included in the radio frequency link, it can be flexibly adjusted according to actual needs, and will not be described in detail here.
  • the combiner module in the base station is a combiner, and the combiner is used to combine the signals of the three radio frequency links to obtain a combined signal, or the combiner is used to combine the signals in the base station Signals of multiple radio frequency links including the three radio frequency links are combined and processed to obtain a combined signal.
  • the function of the combiner may be implemented by an adder, that is, the combiner may be an adder.
  • the optical module in the base station may include an electro-optic conversion component such as an LD, and the optical module may send the signal converted by the electro-optic conversion component to the central station.
  • the optical module in the base station may further include a photoelectric conversion component such as a PD, and the photoelectric conversion component is used to convert a signal from the central station into an electrical signal.
  • the feature calculation module in the base station may include a photoelectric converter, a filter module, a power amplification module, an analog feedback module, a digital feedback module, an iterative calculation module, and the like.
  • the analog feedback module is mainly used to perform analog-to-digital conversion on the signal, which can be realized by an analog-to-digital converter;
  • the digital feedback module is the above-mentioned feedback module, which is used to perform delay correction processing on the signal.
  • the signal f1 of the first radio frequency link and the signals f2 and f3 received by the two second radio frequency links are sent to the combiner after a series of radio frequency processing, and the combined The circuit breaker completes the combination to obtain the electrical signal of the combination of the signal f1, the signal f2 and the signal f3.
  • the feature calculation module since the feature calculation module has not sampled the signal for calculation, the feature calculation module has no output, and the signal f1 does not change when passing through the adder.
  • the combined electrical signal of signal f1, signal f2 and signal f3 is transmitted to the electro-optical converter of the optical module, and the electro-optical converter can convert the electrical signal into an optical signal and send it to the central station through the optical transmission medium.
  • the feature calculation module can sample the optical signal converted by the electro-optical converter, and convert the sampled optical signal into an electrical signal through the photoelectric converter.
  • the electro-optic converter is a nonlinear component. Due to the nonlinear characteristics of the electro-optic converter, in the process of electro-optical conversion of the electrical signal combined with the signal f1, the signal f2 and the signal f3, the signal f2 and the signal f3 will interact with each other.
  • the modulation effect produces a nonlinear distortion signal of second-order intermodulation
  • the nonlinear distortion signal is expressed as imd2 (the frequency band of the signal imd2 overlaps with the frequency band of the signal f1)
  • the output signal of the photoelectric converter includes the signal f1 and the signal f2 , signal f3 and signal imd2
  • the signal output by the photoelectric converter after photoelectric conversion of the optical signal also includes signal f1, signal f2, signal f3 and signal imd2.
  • the signal containing only the same frequency band as the signal f1 can be obtained, that is, the target signal, which includes part or all of the signal f1 and the signal imd2 in the same frequency band as the signal f1 (for For convenience of description, it is still referred to as the signal imd2) in the embodiment of the present application.
  • the target signal reaches the digital feedback module after corresponding processing by the power amplification module and the analog feedback module. After the digital feedback module performs delay correction processing on the target signal, signal f2 and signal f3, it sends the obtained corrected target signal, signal f2 and signal f3 to the iterative calculation module.
  • the iterative calculation module calculates the first nonlinear distortion prediction signal according to the corrected target signal, signal f2, and signal f3, and sends the calculated first nonlinear distortion prediction signal to the predistortion processing module on the first radio frequency link such as in the adder. Thereafter, the signal f1 received on the first radio frequency link is processed by an adder, and after being subtracted from the first nonlinear distortion prediction signal (predicted imd2 signal), it is transmitted to the electro-optical converter of the optical module through related components.
  • the generated imd2 signal and the previously subtracted first nonlinear distortion signal compensate each other, so that the imd2 signal is basically removed from the optical signal obtained by the electro-optical converter, thereby Avoid the interference of imd2 signal to signal f1 as much as possible.
  • the reception of signals by the first radio frequency link and the two second radio frequency links is synchronous, that is, the three radio frequency links receive corresponding three-way signals at the same time.
  • the digital feedback module samples and latches the signals of the two second radio frequency links through the latch module, and sends the latched signals to the correlator, wherein the latched two second
  • the signals of the radio frequency link are represented as the signal f2_latch and the signal f3_latch respectively, and the correlator predicts and calculates the nonlinear distortion signal generated after the signal f2_latch and the signal f3_latch pass through the electro-optical converter, and obtains the corresponding nonlinear distortion prediction signal, and
  • the nonlinear distortion signal and the target signal fb are subjected to correlation processing to obtain a correlation signal of a nonlinear component, and when the threshold judgment module determines that the correlation value of the correlation signal is greater than or equal to a set threshold, the correlation signal is sent to the delay calculation module .
  • the time delay calculation module calculates the time delays between the target signal fb and the signals f2 and f3 according to the relevant signals, and sends them to the time delay alignment module.
  • the time delay alignment module can extract signals with consistent time delays from the target signal fb, signal f2, and signal f3 respectively according to the time delays, and send them to the iterative calculation module.
  • the signal extracted by the delay alignment module from the target signal is the signal fb_align
  • the signal extracted from the signal f2_latch is the signal f2_latch_align
  • the signal extracted from the signal f3_latch is the signal f3_latch_align
  • there is no difference between the signal fb_align, the signal f2_latch_align and the signal f3_latch_align There is a delay.
  • FIG. 8 or FIG. 9 is only an illustration of the system architecture applicable to the embodiment of the present application.
  • the system architecture applicable to the embodiment of the application Other entities can also be added, or some entities can be reduced, and other structures can also be added or some structures (or components) can be reduced in the terminal structure shown in FIG. 8 or FIG. 9 .
  • the various components shown in Fig. 8 or Fig. 9 above are only examples of components that can realize corresponding functions, and each component can also be replaced with other components that can realize corresponding functions.
  • the base station has a mixed digital-analog structure, so in terms of the function design of the base station, it has greater flexibility than the base station architecture with a conventional pure analog design, and at the same time has unique advantages in performance.
  • the receiving link of the ROF system by designing a feedback channel including the photoelectric conversion module and the feature calculation module in the optical module, the coupling sampling of the nonlinear component signal is realized through the internal feedback coupling of the optical module, and through the feedback The channel is looped back to the head-end digital link (for example, the above-mentioned first radio frequency link), so that the modeling calculation of the nonlinear distortion signal and the pre-distortion correction of the radio frequency link signal are realized at the base station side.
  • the head-end digital link for example, the above-mentioned first radio frequency link
  • the nonlinear distortion correction scheme shown in FIG. 8 or FIG. 9 may also be called a small loop correction scheme.
  • the nonlinear distortion generated by the nonlinear components in the base station can be solved, and the impact of the head-end nonlinearity on the entire ROF system can be reduced.
  • the application of the nonlinear signal processing structure and method provided by the present application in the receiving link of the ROF system is used as an example for illustration.
  • the nonlinear signal processing structure provided by the above embodiments The sum method can also be applied in the transmission link of the ROF system.
  • the nonlinear signal processing structure and method provided by the above embodiments can be applied not only at the base station side, but also at the central station side. For specific applications, refer to relevant introductions in the above embodiments, and details will not be repeated here.
  • FIG. 10 is a comparative schematic diagram of an optical module structure provided by an embodiment of the present application.
  • the single-transmit-single-receive (1T1R, that is, one antenna is responsible for signal transmission and reception) analog optical module in the current base station structure is a three-port module, including one for uplink An input electrical port for receiving electrical signals in the link, an output electrical port for sending signals in the downlink, and a transmission optical port for transmitting optical signals, which are respectively port 1 shown in (a) schematic diagram , port 2, and port 3.
  • the optical module in the base station is a four-port module, including an input electrical port for receiving electrical signals in the uplink, and an output electrical port for sending signals in the downlink.
  • port a transmission optical port for transmitting optical signals
  • an electrical signal coupling port for transmitting sampling which are respectively port 1, port 2, port 3 and port 4 shown in (b) schematic diagram.
  • the port 2, the port 3 and the port 4 are respectively the first port, the second port and the third port described in the above embodiment.
  • each 1T1R may correspond to one feedback channel (including the feature calculation module and front and back links), or multiple 1T1Rs may share one feedback channel.
  • FIG. 11 is a schematic diagram of a simplified structure of a base station structure provided by an embodiment of the present application.
  • the structure on each radio frequency link can be divided into an analog link and a forward link , where the analog link is mainly used to implement analog signal processing functions such as signal transmission and analog-to-digital conversion, and the forward link is used to implement digital signal processing functions related to nonlinear distortion signal prediction and pre-distortion correction.
  • the two first The forward link part of the second radio frequency link may be used to send signals to the feature calculation module, etc., and the forward link part of the first radio frequency link may be used for predistortion correction processing.
  • the optical module mainly includes an electro-optical conversion module and a photoelectric conversion module. Reference may be made to the introduction in the foregoing embodiments.
  • the feedback link can be combined with the existing system link to build a feedback channel, and realize the time delay alignment of the useful signal and the nonlinear distortion signal, mainly including the above-mentioned feedback module.
  • the calculation link can use the useful signal processed by the feedback link and the nonlinear distortion signal to perform calculation modeling, calculate the nonlinear distortion prediction signal, and feed it back to the forward link of the first radio frequency link, so that the first radio frequency
  • the forward link of the radio frequency link performs predistortion processing on the signal on the first radio frequency link according to the nonlinear distortion prediction signal, so as to compensate the nonlinear distortion in the link.
  • each functional module in each embodiment of the present application may be a separate It exists physically, or two or more modules can be integrated in one module.
  • Fig. 12 is a schematic diagram of a base station and a central station provided by an embodiment of the present application.
  • the base station may include multiple radio frequency links (such as the radio frequency chain shown in Fig. 12 1, radio frequency link 2), optical module, feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2.
  • each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and transmit the one signal to the optical module after performing radio frequency processing on the one signal.
  • the optical module is configured to perform electro-optic conversion processing on the multiple signals from the multiple radio frequency links, obtain an optical signal including the processed multiple signals, and send the optical signal to the center Station, receives the target signal from the central station, performs photoelectric conversion processing on the target signal, and sends the processed target signal to the feature calculation module, wherein there are The first radio frequency link and at least one second radio frequency link, the optical module includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate a nonlinear distorted signal, The frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link, and the optical signal also includes the nonlinear distortion signal; the target signal includes the frequency band corresponding to the first radio frequency link signal in the frequency band.
  • the base station further includes a combiner module (not shown in FIG. 12 ), the combiner module is used to receive multiple signals from the multiple radio frequency links, and combine the multiple signals Perform combination processing to obtain a combination signal, and send the combination signal to the optical module.
  • the optical module is used to receive the combined signal from the combined module, and perform electro-optical conversion processing on the combined signal to obtain the optical signal.
  • the combining module may be a combiner.
  • Each second radio frequency link is further configured to perform radio frequency processing on a received signal of a corresponding frequency band, and then send the obtained signal to the feature calculation module.
  • the feature calculation module is configured to receive the target signal from the optical module; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and calculate the The nonlinear distortion prediction signal is sent to the first radio frequency link, wherein the nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
  • the first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
  • the optical module includes an electro-optical conversion module, the electro-optical conversion module is used to perform electro-optical conversion processing on the multi-channel signal to obtain an optical signal, and the electro-optical conversion module includes the nonlinear component , the nonlinear component can be used to perform electro-optical conversion processing on signals.
  • the electro-optic conversion module may be an LD.
  • the optical module After the optical module sends the converted optical signal to the central station, it can receive the target signal from the central station, perform photoelectric conversion processing on the target signal, and send the processed target signal to the Feature calculation module.
  • the optical module may directly receive the target signal from the central station, and send the target signal to the feature calculation module.
  • the optical module may receive a downlink signal from the central station, perform photoelectric conversion processing on the downlink signal, and send the processed downlink signal to the feature calculation module, wherein the downlink signal includes the target signal and other signals to be sent to the base station.
  • the feature calculation module may obtain the target signal by receiving the downlink signal from the optical module and performing filtering processing on the downlink signal.
  • the feature calculation module includes a filter module and an iterative calculation module.
  • the filtering module is configured to receive the downlink signal from the optical module, and filter the downlink signal to obtain the target signal.
  • the filtering module is a filter.
  • the feature calculation module may also include a frequency division module, the frequency division module is connected to the optical module and the filter module, and the frequency division module may be used to receive the downlink from the optical module signal, performing frequency division processing on the downlink signal to obtain a signal in the frequency band corresponding to the first radio frequency link, and sending the signal in the frequency band corresponding to the first radio frequency link to the filter, then the filter It can be used to perform filtering processing on the signal in the frequency band corresponding to the first radio frequency link to obtain the target signal.
  • a frequency division module the frequency division module is connected to the optical module and the filter module, and the frequency division module may be used to receive the downlink from the optical module signal, performing frequency division processing on the downlink signal to obtain a signal in the frequency band corresponding to the first radio frequency link, and sending the signal in the frequency band corresponding to the first radio frequency link to the filter, then the filter It can be used to perform filtering processing on the signal in the frequency band corresponding to the first radio frequency link to obtain the target signal.
  • the feature calculation module further includes a feedback module.
  • a feedback module For the structure and function of the feedback module, please refer to the description of the feedback module in the first embodiment above, and will not be repeated here.
  • the central station may include an optical module and a signal processing module.
  • the optical module is configured to receive an optical signal from the base station, perform photoelectric conversion processing on the optical signal to obtain an electrical signal, and send the electrical signal to the signal processing module, wherein the electrical signal contains a nonlinear Distorted signals, multiple signals received by multiple radio frequency links of the base station through antennas, the number of the multiple radio frequency links is greater than or equal to 2, and the first radio frequency link and the first radio frequency link exist in the multiple radio frequency links
  • the base station includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate the nonlinear distortion signal, and the nonlinear distortion
  • the frequency band of the signal overlaps with the frequency band corresponding to the first radio frequency link.
  • the optical module of the central station may include a photoelectric conversion module, and the photoelectric conversion module is configured to receive an optical signal from a base station and convert the optical signal into an electrical signal.
  • the photoelectric conversion module includes nonlinear components.
  • the photoelectric conversion module may be a PD.
  • the optical module of the base station obtains an optical signal through the electro-optical conversion module
  • the optical signal is sent to the central station, and the optical module of the central station transmits the optical signal through the photoelectric conversion module
  • the optical signal is converted into an electrical signal and sent to a signal processing module.
  • the signal processing module is configured to receive the electrical signal from the optical module, extract the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal, and send the target signal to the Described optical module.
  • the signal processing module includes a filtering module, and the filtering module is configured to receive the electrical signal from the optical module, perform filtering processing on the electrical signal, obtain the target signal, and send it to the Described optical module.
  • the optical module is further configured to perform electro-optical conversion processing on the target signal, and send the processed target signal to the base station. Specifically, after the optical module receives the target signal from the signal processing module, as an optional implementation manner, the optical module may directly and separately send the target signal to the base station. As another optional implementation manner, the optical module may perform electrical-optical conversion processing on the target signal and other signals to be sent to the base station, to obtain the target signal and other signals to be sent to the base station the downlink signal of the signal, and send the downlink signal to the base station.
  • the optical module of the central station may further include an electrical-to-optical conversion module, and the electrical-to-optical conversion module is configured to convert an electrical signal into an optical signal, and then send the optical signal to the base station.
  • the electro-optic conversion module includes nonlinear components.
  • the electro-optic conversion module may be an LD.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency.
  • the first frequency is the sum of starting frequencies of corresponding frequency bands of the two second radio frequency links
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, so The second frequency is the difference between the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the central station after the base station sends the signal passing through the nonlinear components and the nonlinear distortion signal generated by the signal passing through the nonlinear components to the central station, the central station obtains the target signal based on the signal, and then sends the target signal back to base station, and the base station calculates the nonlinear distortion characteristic parameters of the nonlinear components according to the target signal.
  • the accuracy of the nonlinear distortion characteristics of linear components is the accuracy of the nonlinear distortion characteristics of linear components.
  • the base station After the base station determines the nonlinear distortion parameter of the nonlinear component, it combines the parameter with the signal currently transmitted on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear component, which can improve the determined nonlinear
  • the accuracy of the distortion prediction signal can further pre-distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components
  • the correction of the problem improves the accuracy of nonlinear distortion correction.
  • the signal on which the base station calculates the nonlinear distortion characteristic parameters is passed back by the central station, so the transmission path of the signal includes some transmission links in the central station, and the nonlinear distortion problem in the base station
  • the correction method can correct the entire link where the nonlinear components are located. Therefore, while correcting the nonlinear distortion problems in the base station, this scheme can also correct some nonlinear distortion problems in the central station, thereby improving the communication between the central station and the central station. The accuracy of communication between base stations.
  • the base station and the central station provided in the above embodiments of the present application will be described below in combination with specific application scenarios, taking one second radio frequency link among the plurality of radio frequency links as an example, in combination with specific examples.
  • Fig. 13 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • the base station and the central station provided by the embodiment of the present application can be applied in a ROF system, and the base station includes at least two radio frequency links, which are respectively a first radio frequency link and a second radio frequency link road.
  • the two radio frequency links can respectively receive signals of two different frequency bands through antennas.
  • the road signal is denoted as f5.
  • the base station shown in Figure 13 When the base station shown in Figure 13 is applied to the ROF system, the base station may also include some components or modules in the ROF system shown in Figure 5 above, and other components or modules for signal processing, specifically Refer to the relevant introduction in the first embodiment above, which will not be repeated here.
  • the signal f4 received by the first radio frequency link and the signal f5 received by the second radio frequency link are sent to the combiner after a series of radio frequency processes, and the combiner completes Combined to obtain the electrical signal of signal f4 and signal f5 combined, the electrical signal is transmitted to the electro-optical converter of the optical module, the electro-optical converter can convert the electrical signal into an optical signal and send it to the central station through the optical transmission medium.
  • the electro-optical converter is a nonlinear component.
  • the frequency component of the signal f5 will undergo intermodulation.
  • the nonlinear distortion signal of the second-order intermodulation the nonlinear distortion signal is expressed as imd2 (the frequency band of the signal imd2 overlaps with the frequency band of the signal f4)
  • the signal sent by the electro-optical converter of the base station to the central station includes the signal f4, Signal f5 and signal imd2.
  • the photoelectric conversion module of the central station converts the optical signal into an electrical signal, and sends the electrical signal to the signal processing module.
  • the signal processing module of the central station can obtain the signal containing only the same frequency band as the signal f4 after filtering the electrical signal through a filter, that is, the target signal, which includes the signal f4 and the signal imd2 in the same frequency band as the signal f4 Part or all of the signals (for ease of description, it is still referred to as the signal imd2 in this embodiment of the application).
  • the target signal and other signals to be sent to the base station are sent to the base station together after passing through the electro-optic converter of the central station.
  • the photoelectric converter of the base station receives the signal from the central station, it performs photoelectric conversion processing on the signal to obtain a corresponding electrical signal, and sends it to the feature calculation module.
  • the characteristic calculation module of the base station performs frequency division processing on the electrical signal through the frequency division module to obtain a signal corresponding to the frequency band of the first radio frequency link, and performs filtering processing on the signal through a filter to obtain a target signal, and the target signal is passed through the power After corresponding processing by the amplification module and the analog feedback module, it reaches the digital feedback module. After the digital feedback module performs delay correction processing on the target signal and signal f5, the obtained signal is sent to the iterative calculation module.
  • the iterative calculation module calculates the first nonlinear distortion prediction signal according to the target signal and signal f5, and sends the calculated first nonlinear distortion prediction signal to the adder on the first radio frequency link, and processes it through the adder, After subtracting the first nonlinear distortion prediction signal (predicted imd2 signal) from the signal f4 on the first radio frequency link, it is transmitted to the electro-optical converter of the optical module through related components.
  • the generated imd2 signal and the previously subtracted first nonlinear distortion signal compensate each other, so that the imd2 signal is basically removed from the optical signal obtained by the electro-optical converter, thereby Avoid the interference of imd2 signal to signal f4 as much as possible.
  • the photoelectric converter and the electro-optical converter are also nonlinear components, if the signal from the base station passes through the photoelectric converter or the electro-optical converter also generates If there is a non-linear distortion signal overlapping the frequency band of the signal f4, part or all of the signals in the non-linear distortion signal overlapping the frequency band of the signal f4 will also be carried in the target signal and sent back to the base station, then the base station When calculating the nonlinear distortion prediction signal based on the target signal, the nonlinear distortion problem in the process of the signal passing through the central station can be considered, and some nonlinear distortion in the central station can be corrected during the pre-distortion process, so as to further Improve performance in correcting nonlinear distortions of ROF systems.
  • the signal starts from the receiving port of the air interface antenna of the base station, undergoes a radio frequency link in the base station, and the electro-optical converter of the optical module generates nonlinearity, and then transmits through the optical fiber, receives it at the photoelectric converter of the central station, and then passes through the central station.
  • the signal processing of the station is sent by the electro-optical converter on the transmitting side, and then received by the photoelectric converter of the base station through the optical fiber loopback. After frequency division, it is coupled to the feedback link through the feedback channel for nonlinear distortion signal prediction and other processing.
  • the original optical modules of the base station and the central station can be used to realize the large-loop sampling of the nonlinear distortion signal, which is sent to the feature calculation module of the base station to predict the nonlinear distortion signal. Therefore, the modeling calculation of the nonlinear distortion signal on the link between the base station and the central station and the pre-distortion correction of the radio frequency link signal are realized on the base station side. Therefore, the above nonlinear distortion correction scheme shown in FIG. 13 may also be referred to as a giant loop correction scheme.
  • the nonlinear distortion generated by the nonlinear components in the base station and the central station can be solved, and the influence of the nonlinearity in the base station and the central station on the entire ROF system can be reduced.
  • FIG. 14 is a schematic diagram of a central station provided by an embodiment of the present application.
  • the central station may include an optical module, a signal processing module, and a feature calculation module.
  • the optical module is configured to receive an optical signal from at least one base station, perform photoelectric conversion processing on the optical signal of each base station in the at least one base station, obtain an electrical signal of each base station, and convert the electrical signal of each base station to sent to the signal processing module and the feature calculation module.
  • the electrical signal of any base station includes nonlinear distortion signals, multiple signals received by multiple radio frequency links of the base station through antennas, the number of the multiple radio frequency links is greater than or equal to 2, and the multiple There are a first radio frequency link and at least one second radio frequency link in the radio frequency links, the base station contains nonlinear components, and the signal of the at least one second radio frequency link is generated after passing through the nonlinear components For the nonlinear distorted signal, a frequency band of the nonlinear distorted signal overlaps with a frequency band corresponding to the first radio frequency link.
  • the optical module sends the electrical signal of each base station to the signal processing module respectively through different links.
  • the optical module sends the electrical signal of each base station to the feature calculation module through different links.
  • the feature calculation module is used to respectively receive the electrical signal from each base station of the optical module; respectively perform feature calculation processing on the electrical signal of each base station to obtain a nonlinear distortion prediction signal corresponding to each base station, and respectively The nonlinear distortion prediction signal corresponding to each base station is sent to the signal processing module; wherein, the feature calculation processing on the electrical signal of any base station includes the following steps: extracting the first radio frequency chain from the electrical signal target signal in a corresponding frequency band, and at least one signal from the at least one second radio frequency link is respectively extracted from the electrical signal; according to the target signal and at least one signal of the at least one second radio frequency link One channel of signals calculates the nonlinear distortion prediction signal, wherein the nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
  • the signal processing module is configured to respectively receive electrical signals from each base station of the optical module; perform radio frequency processing on the electrical signals of the at least one base station to obtain a target combining signal; wherein, the target combining signal includes The signal of the frequency band corresponding to the first radio frequency link; the radio frequency processing may include combination processing and frequency division processing; respectively receive the nonlinear distortion prediction signal corresponding to each base station from the feature calculation module; The nonlinear distortion prediction signals corresponding to the base stations perform distortion correction processing on the target combined signal.
  • the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency
  • the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency
  • the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link
  • the second frequency is the The second radio frequency link corresponds to twice the cutoff frequency of the frequency band.
  • the first frequency is the sum of starting frequencies of corresponding frequency bands of the two second radio frequency links
  • the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, so The second frequency is the difference between the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links.
  • the optical module includes a photoelectric conversion module, and the photoelectric conversion module is configured to respectively perform photoelectric conversion processing on the optical signals from the at least one base station to obtain electrical signals.
  • the photoelectric conversion module includes nonlinear components, and the nonlinear components can be used to perform photoelectric conversion processing on signals.
  • the photoelectric conversion module may be a PD.
  • the signal processing module includes a radio frequency processing module, a digital processing and compensation module.
  • the radio frequency processing module is configured to perform radio frequency processing on the signal corresponding to each base station received by the optical module, for example, it may include: performing combination processing on the electrical signals of the at least one base station to obtain a combined signal, and The combined signal is subjected to frequency division processing to obtain a signal of a frequency band corresponding to each radio frequency link.
  • the signal of the frequency band corresponding to each radio frequency link includes the signal of the frequency band corresponding to the at least one base station and the non-linear distortion signal overlapping with the frequency band. For example, as shown in FIG.
  • the digital processing and compensation module is used to sequentially perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station. Specifically, the digital processing and compensation module sequentially subtracts the nonlinear distortion prediction signal corresponding to each base station from the target combined signal to obtain the target combined signal from which the nonlinear distortion signal has been removed.
  • the signal sent by the first base station to the central station includes the signal of the first base station A signal on the first radio frequency link, a signal of the second radio frequency link of the first base station, and a nonlinear distorted signal generated after the signal of the second radio frequency link passes through a nonlinear component.
  • the signal sent by the second base station to the central station includes the signal on the first radio frequency link of the second base station, the signal of the second radio frequency link of the first base station, and the signal of the second radio frequency link after passing through the nonlinear components The resulting non-linear distortion signal.
  • the combined signal obtained by combining the electrical signals of the at least one base station by the radio frequency processing module includes at least the above six signals.
  • the radio frequency processing module performs frequency division processing on the combined signal to obtain the target combined signal (including the signal of the first radio frequency link of the first base station, the nonlinear distortion signal from the first base station, and the second The signal of the first radio frequency link of the base station, the nonlinear distortion signal from the second base station), and then perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station.
  • the signal processing module may first perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal, and then according to the second base station The corresponding nonlinear distortion prediction signal performs distortion correction processing on the first target combined signal to obtain a second target combined signal.
  • the signal processing module obtains the first target combined signal by subtracting the target combined signal from the nonlinear distortion prediction signal corresponding to the first base station, and obtains the first target combined signal by Subtracting the nonlinear distortion prediction signal corresponding to the second base station to obtain the second target combined signal.
  • the radio frequency processing module when it performs radio frequency processing on the signals corresponding to each base station received by the optical module, it may also perform combined processing on the electrical signals of the at least one base station to obtain combined signal. Then the combined signal is sent to the digital processing and compensation module as the target combined signal. The digital processing and compensation module is used to sequentially subtract the target combined signal from the nonlinear distortion prediction signal corresponding to each base station to obtain the combined signal of the at least one base station after the nonlinear distortion signal is removed. During subsequent processing of the combined signal of the at least one base station, the central station may perform frequency division processing on the signal to obtain a signal in a frequency band corresponding to each radio frequency link.
  • the signal processing module may also only include a digital processing and compensation module, and then the digital processing and compensation module may separately receive the optical module according to the nonlinear distortion prediction signal corresponding to each base station. Distortion correction processing is performed on the signals of each base station, thereby realizing independent processing of signals from different base stations.
  • the feature calculation module may further include a signal control module in addition to the specific structure described in the first or second embodiment above.
  • the signal control module is used to selectively control the electrical signal from the at least one base station of the optical module, so that the feature calculation module only receives the electrical signal from one base station at a time.
  • the signal control module may be a single-pole multi-throw switch, wherein the fixed end of the single-pole multi-throw switch is connected to the filter module in the characteristic calculation module, and the movable end of the single-pole multi-throw switch is respectively connected to the transmission of the at least one The link connection of the electrical signal of the base station.
  • the electrical signal of a certain base station transmitted by a certain link can be selected to be transmitted to the characteristic calculation module through the single-pole multi-throw switch, so as to facilitate the calculation of the nonlinear distortion prediction signal for the base station.
  • the central station sets a corresponding feature calculation module for each connected base station, and then the photoelectric conversion module of the central station obtains electrical signals from at least one base station.
  • the central station couples the signal to the corresponding feature calculation module on the transmission link corresponding to each signal, and calculates the nonlinear distortion prediction signal of the corresponding base station through the feature calculation module.
  • the feature calculation module corresponding to each base station determines the nonlinear distortion prediction signal corresponding to the base station, it sends the determined nonlinear distortion prediction signal to the signal processing module respectively.
  • the signal processing module can respectively perform distortion correction processing on the electrical signal of each base station according to the nonlinear distortion prediction signal corresponding to each base station, so that each individual signal component can be nonlinearly constructed. Mode and distortion correction processing, so as to ensure the best performance.
  • the signal processing module after the signal processing module performs combination processing and frequency division processing on the electrical signal of the at least one base station, it sequentially performs frequency division
  • the obtained electrical signal is subjected to distortion correction processing, so that the signals after aggregation and channel separation can be separated to achieve the equivalent effect of multi-channel signal separation, and then nonlinear modeling and distortion correction processing can be performed for each component signal, which can Avoid setting up additional physical channels.
  • the structures, functions, and characteristics of some modules can refer to the relevant introductions in the above-mentioned Embodiment 1 or Embodiment 2, and will not be described in detail in this embodiment.
  • the central station can calculate the nonlinear distortion of the nonlinear component based on the signal actually passing through the nonlinear component (in the base station or the central station) and the nonlinear distortion signal actually generated after the signal passes through the nonlinear component
  • the characteristic parameter can improve the accuracy of determining the nonlinear distortion characteristic of the nonlinear component.
  • the central station determines the nonlinear distortion parameters of the nonlinear components, it combines the parameters with the current transmission signal on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear components, which can improve the determined nonlinear distortion parameters.
  • the accuracy of the linear distortion prediction signal can further distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components
  • the correction of the problem improves the accuracy of nonlinear distortion correction.
  • the central station can perform nonlinear distortion correction processing on signals from multiple base stations, which improves the performance and efficiency of nonlinear distortion correction.
  • the base station provided by the above-mentioned embodiments of the present application will be described below in combination with specific application scenarios, taking a first radio frequency link and a second radio frequency link in each base station as an example, and specific examples.
  • Fig. 15 is a schematic diagram of an ROF system provided by an embodiment of the present application.
  • the central station provided by the embodiment of the present application can be applied to an ROF system, and the central station includes an optical module, a feature calculation module, and a signal processing module.
  • the ROF system further includes n base stations, where n is a positive integer.
  • each base station includes two radio frequency links, namely a first radio frequency link and a second radio frequency link.
  • the two radio frequency links can respectively receive signals of two different frequency bands through the antenna. For example, as shown in FIG.
  • the second signal received by the channel is expressed as f2_N, where N is less than or equal to n and is a positive integer.
  • N is less than or equal to n and is a positive integer.
  • the frequency bands corresponding to the first radio frequency links of each base station are the same, and the second radio frequency links of each base station
  • the frequency bands corresponding to the channels are the same, and the signals of the second radio frequency links of each base station pass through nonlinear components to generate nonlinear distortion signals overlapping with the frequency bands corresponding to the first radio frequency links.
  • the signal f1_N received by the first radio frequency link of the Nth base station and the signal f2_N received by the second radio frequency link are sent to the combiner after a series of radio frequency processing, and then The combiner completes the combination to obtain the combined electrical signal of signal f1_N and signal f2_N, and the electrical signal is transmitted to the electro-optical converter of the optical module, which can convert the electrical signal into an optical signal and send it to central station.
  • the electro-optical converter is a nonlinear component.
  • the frequency component of the signal f2_N will undergo intermodulation.
  • the nonlinear distortion signal of the second-order intermodulation the nonlinear distortion signal is expressed as imd2_N (the frequency band of the signal imd2_N overlaps with the frequency band of the signal f1_N), then the signal actually sent by the electro-optical converter of the base station to the central station contains the signal f1_N , signal f2_N and signal imd2_N, expressed as f1_N+f2_N+imd2_N.
  • the photoelectric conversion module of the central station After receiving the optical signal, the photoelectric conversion module of the central station converts the optical signal into an electrical signal, and sends the electrical signal to the signal processing module.
  • the signal processing module of the central station performs combination processing and frequency division processing on the electrical signals of the at least one base station through the radio frequency processing module to obtain signals corresponding to frequency bands of different radio frequency links.
  • the signal obtained after frequency division at least includes a signal of a frequency band corresponding to the first radio frequency link and a signal of a frequency band corresponding to the second radio frequency link.
  • the feature calculation module calculates the nonlinear distortion prediction signal corresponding to each base station according to the electrical signal (f1_N+f2_N+imd2_N) of each base station, and sends it to the signal processing module.
  • the signal processing module sequentially subtracts the nonlinear distortion prediction signal corresponding to each base station from the signal in the frequency band corresponding to the first radio frequency link to implement nonlinear distortion correction for the signal in the frequency band corresponding to the first radio frequency link.
  • both are one-to-one nonlinear distortion correction, that is, one nonlinear distortion correction structure corresponds to one base station module or communication link.
  • a central station is connected to multiple base stations (for example, a central station is connected to eight base stations, etc.), and these multiple base stations share the resources of a central station, so the signals of multiple base stations will eventually converge. to a central station.
  • the central station by setting the correction link at the central station, one driver and multiple corrections at the central station are realized, that is, the central station can not only correct the nonlinear distortion caused by the nonlinear device in the base station, but also correct the Nonlinear distortion caused by nonlinear devices.
  • a new ROF architecture based on digital-analog hybrid is provided, which is conducive to adopting flexible digital links, more accurately solving the nonlinear distortion problem of analog devices in the ROF network, and solving the non-linear distortion caused by optical devices and the like.
  • the constraint of the linear component on the frequency planning of the ROF system realizes the high-performance and low-cost design of ROF, which can improve the performance of 5G and future multi-mode large-bandwidth high-speed transmission and enable low-cost deployment of sites.
  • the solution to the nonlinear distortion problem caused by the nonlinear components in the optical module of the base station is used as an example to introduce the solution provided by the application, but the application scenario of the solution in the application is not limited to this .
  • the scheme provided by this application can effectively solve it.
  • the scheme provided by this application is mainly described according to the correction of nonlinear distortion components.
  • the scheme provided in this application can also be applied to linear distortion component correction.
  • this embodiment of the present application also provides a nonlinear signal processing method, which can be applied to a base station or a central station.
  • a nonlinear signal processing method which can be applied to a base station or a central station.
  • the method includes:
  • the base station calculates target parameters according to the target signal, wherein the target signal includes: a first signal passing through a nonlinear component, and a nonlinear distortion signal generated after at least one second signal passes through a nonlinear component, and the nonlinear The frequency band of the distorted signal overlaps with the frequency band of the first signal, and the target parameter is used to characterize the nonlinear distortion characteristic of the nonlinear component.
  • the frequency band of the first signal is the first frequency band
  • the frequency bands of the signals in the at least one second signal may be the same or different.
  • the first signal may be the signal S F3 in the scene one shown in FIG. 3
  • the at least one second signal may include the signal S F1 and the signal S F2 in the scene two shown in FIG. 3
  • the first signal may be the signal S F3 in the second scene shown in FIG. 3
  • the at least one second signal may include the signal S F1 and the signal S F2 in the second scene shown in FIG. 3
  • the first signal may be the signal S F3 in the third scene shown in FIG. 3
  • the at least one second signal may include the signal S F1 in the third scene shown in FIG. 3 .
  • the base station may calculate the target parameters according to the set first calculation model and the target signal, wherein the first calculation model is used to represent the multi-channel signals input to the nonlinear components The corresponding relationship between one channel of signal, the nonlinear distortion signal output by the nonlinear component with the same frequency band as the one of the signal, and the nonlinear distortion characteristic parameters of the nonlinear component.
  • the base station calculates a target prediction signal according to the at least one second signal, where the target prediction signal is a prediction signal of the nonlinear distortion signal.
  • the base station may calculate the target prediction signal according to the set second calculation model and the at least one second signal, wherein the second calculation model is used to represent the relationship between the at least one signal passing through the nonlinear component and the The corresponding relationship between the nonlinear distortion signals generated after the at least one signal passes through the nonlinear components.
  • the base station corrects the target prediction signal according to the target parameter to obtain a nonlinear distortion prediction signal.
  • the nonlinear distortion prediction signal is a modified prediction signal of the nonlinear distortion signal.
  • the base station may multiply the target parameter by the target prediction signal to obtain the nonlinear distortion prediction signal.
  • the base station can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component based on the nonlinear distortion signal caused by the nonlinear component, which can improve the accuracy of the determined nonlinear distortion prediction signal Further, the useful signal can be pre-distorted according to the determined nonlinear distortion prediction signal, so as to realize the correction of the nonlinear distortion problem caused by the nonlinear components and improve the accuracy of nonlinear distortion correction.
  • an embodiment of the present application also provides a device, the device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory , realizing the nonlinear signal processing method shown in FIG. 16 above.
  • this embodiment of the present application also provides a chip
  • the chip may include the components or modules included in the base station in the first embodiment above; or the chip may include the components or modules in the second embodiment above The components or modules included in the base station; or the chip may include the components or modules included in the central station in the second embodiment above; or the chip may include the components included in the central station in the third embodiment above or modules.
  • the embodiments of the present application also provide a communication system, the communication system at least includes: the base station provided in the first embodiment above, or the base station and the central station provided in the second embodiment above, Or the central station provided in the third embodiment above.

Abstract

The present application discloses a base station, a central station, and a nonlinear signal processing method. The base station comprises multiple radio frequency links, an optical module, and a feature calculation module; the optical module is used to execute electro-optical conversion on signals of the multiple radio frequency links, send obtained optical signals to the central station, and execute photoelectric conversion on the optical signals to obtain electrical signals; the multiple radio frequency links comprise a first radio frequency link and at least one second radio frequency link, the optical module contains a nonlinear component, a signal of the at least one second radio frequency link passes through the nonlinear component and then generates a nonlinear distortion signal that overlaps with a corresponding frequency band of the first radio frequency link, and the optical signal contains the nonlinear distortion signal; the feature calculation module is used to extract a target signal of the corresponding frequency band of the first radio frequency link from the electrical signals, and calculate a nonlinear distortion prediction signal according to the target signal and the signal of the at least one second radio frequency link; and the first radio frequency link is used to execute pre-distortion processing on the signal of the corresponding frequency band according to the nonlinear distortion prediction signal.

Description

一种基站、中心站及非线性信号处理方法A base station, central station and nonlinear signal processing method 技术领域technical field
本申请涉及通信技术领域,尤其涉及一种基站、中心站及非线性信号处理方法。The present application relates to the technical field of communication, and in particular to a base station, a central station and a nonlinear signal processing method.
背景技术Background technique
无线通信系统中的无线通信链路上存在较多非线性元器件,例如低噪声放大器,功率放大器(Power Amplifier,PA)、光电转换(Optical-Electro,O/E)元件、电光转换(Electro-Optical,E/O)元件等,这些非线性元器件可能会导致通信链路上的信号产生非线性失真,具体表现为非线性元器件的输出信号中会出现输入信号中所没有的新的频率分量的信号即非线性失真信号,非线性失真信号会对一些正常信号的后续处理造成干扰,影响无线通信系统的性能。There are many nonlinear components on the wireless communication link in the wireless communication system, such as low-noise amplifier, power amplifier (Power Amplifier, PA), photoelectric conversion (Optical-Electro, O/E) components, electro-optical conversion (Electro- Optical, E/O) components, etc. These nonlinear components may cause nonlinear distortion of the signal on the communication link. Specifically, the output signal of the nonlinear component will appear in the output signal of a new frequency that is not in the input signal. The component signal is a nonlinear distortion signal, which will interfere with the subsequent processing of some normal signals and affect the performance of the wireless communication system.
当前为了解决无线通信系统中通信链路上的非线性失真问题,可以通过模拟预失真方式对系统中的非线性元器件的非线性特性进行校正,来降低非线性元器件导致的非线性失真的影响。模拟预失真是指对输入非线性元器件的信号提前进行处理,使得该处理引起的信号变化与信号输入非线性元器件后产生的非线性失真相互抵消,从而对非线性元器件引起的非线性失真进行校正。在上述方法中,对非线性元器件的非线性指标进行校正的链路一般是固定的,在模拟预失真过程中对非线性失真的拟合能力有限,且只能在一定程度上针对性的改善某类非线性元器件的特性,因此该方法对非线性失真的校正能力较低。At present, in order to solve the nonlinear distortion problem on the communication link in the wireless communication system, the nonlinear characteristics of the nonlinear components in the system can be corrected by analog predistortion to reduce the nonlinear distortion caused by the nonlinear components. Influence. Analog predistortion refers to processing the signal input to the nonlinear components in advance, so that the signal change caused by the processing and the nonlinear distortion generated after the signal is input to the nonlinear components cancel each other, so that the nonlinear distortion caused by the nonlinear components Distortion is corrected. In the above method, the link for correcting the nonlinear index of nonlinear components is generally fixed, and the fitting ability of nonlinear distortion in the process of analog predistortion is limited, and can only be targeted to a certain extent Improve the characteristics of certain types of nonlinear components, so this method has a low ability to correct nonlinear distortion.
发明内容Contents of the invention
本申请提供一种基站、中心站及非线性信号处理方法,用以提高计算非线性元器件引起的非线性失真信号的准确度,从而可以进一步提高对非线性元器件引起的非线性失真进行校正或补偿的性能。The application provides a base station, a central station, and a nonlinear signal processing method to improve the accuracy of calculating nonlinear distortion signals caused by nonlinear components, thereby further improving the correction of nonlinear distortion caused by nonlinear components or compensated performance.
第一方面,本申请提供一种基站,包括:多个射频链路、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2;每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号;所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理,得到包含处理后的所述多路信号的光信号;其中,所述光模块中包含非线性元器件,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠,所述光信号中还包含所述非线性失真信号;将所述光信号发送到中心站,及对所述光信号进行光电转换处理得到电信号并将所述电信号发送到所述特征计算模块;每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块;所述特征计算模块,用于从来自所述光模块的所述电信号中提取目标信号;其中,所述目标信号包含所述电信号中包含的所述第一射频链路对应的频段的信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;所述第一射频链路,还用于根据 所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。In the first aspect, the present application provides a base station, including: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2; each radio frequency link is used for Receive one signal of the corresponding frequency band through the antenna, and send the one signal to the optical module after performing radio frequency processing on the one signal; The signal is subjected to electro-optical conversion processing to obtain an optical signal including the processed multi-channel signal; wherein, the optical module includes nonlinear components, and there are a first radio frequency link and at least one radio frequency link among the plurality of radio frequency links The second radio frequency link, the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal corresponds to the frequency band of the first radio frequency link There is overlap, the optical signal also includes the nonlinear distortion signal; sending the optical signal to the central station, and performing photoelectric conversion processing on the optical signal to obtain an electrical signal, and sending the electrical signal to the The feature calculation module; each second radio frequency link is also used to perform radio frequency processing on the received signal of the corresponding frequency band, and then send the obtained signal to the feature calculation module; the feature calculation module is used for from Extracting a target signal from the electrical signal of the optical module; wherein, the target signal includes a signal of a frequency band corresponding to the first radio frequency link contained in the electrical signal; according to the target signal and the signal from the Calculate the nonlinear distortion prediction signal for at least one signal of the at least one second radio frequency link, and send the nonlinear distortion prediction signal to the first radio frequency link, where the nonlinear distortion prediction signal is the A first prediction signal of a nonlinear distortion signal; the first radio frequency link is further configured to perform predistortion processing and radio frequency processing on a signal in a frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and Send the processed signal to the optical module.
在该方案中,基站可以基于先前经过非线性元器件的信号以及该非线性元器件引起的非线性失真信号,对后续信号经过非线性元器件时产生的非线性失真信号进行预测计算,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传输链路上传输的信号进行预失真处理,从而实现对传输链路上信号经过非线性元器件时产生的非线性失真问题的校正,提高进行非线性失真校正的准确度。In this solution, the base station can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component based on the signal that has previously passed through the nonlinear component and the nonlinear distortion signal caused by the nonlinear component, which can improve The accuracy of the determined nonlinear distortion prediction signal can further predistort the signal transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the detection of the signal generated when the signal on the transmission link passes through nonlinear components The correction of nonlinear distortion problem improves the accuracy of nonlinear distortion correction.
在一种可能的设计中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者,当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。In a possible design, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein: when the multiple radio frequency chains When there is a second radio frequency link in the road, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the frequency corresponding to the second radio frequency link. Twice the cutoff frequency of the frequency band; or, when there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum, the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links The second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
在一种可能的设计中,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;根据所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。In a possible design, the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component nonlinear distortion characteristics; calculate the target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameter The target prediction signal is corrected to obtain the nonlinear distortion prediction signal.
在该方案中,基站基于实际经过非线性元器件的信号以及该信号经过非线性元器件后实际产生的非线性失真信号,计算非线性元器件的非线性失真特性参数,能够提高确定非线性元器件的非线性失真特性的准确度,进而提高基于非线性元器件的非线性失真特性参数对目标预测信号进行校正的准确度。In this scheme, the base station calculates the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear components and the nonlinear distortion signal actually generated after the signal passes through the nonlinear components, which can improve the determination of nonlinear components. The accuracy of the nonlinear distortion characteristics of the device is improved, thereby improving the accuracy of correcting the target prediction signal based on the nonlinear distortion characteristic parameters of the nonlinear components.
在一种可能的设计中,所述迭代计算模块,在根据所述目标信号计算目标参数时,具体用于:根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;所述迭代计算模块根据所述至少一个第二射频链路的至少一路信号计算目标预测信号时,具体用于:根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。In a possible design, the iterative calculation module, when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
在该方案中,基站通过利用有用信号与失真信号进行建模计算,对有用信号经过非线性元器件后产生的非线性失真信号进行预测,能够通过计算模型简便、快速、准确的得到所需计算的目标预测信号。In this scheme, the base station predicts the nonlinear distortion signal generated by the useful signal through the nonlinear components by using the useful signal and the distorted signal for modeling calculation, and can obtain the required calculation simply, quickly and accurately through the calculation model target prediction signal.
在一种可能的设计中,所述迭代计算模块,在根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号时,具体用于:将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。In a possible design, when the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
在该方案中,基站通过根据非线性元器件的非线性失真特性参数对预测的非线性失真 信号进行校正,能够进一步提高确定的非线性失真预测信号的准确度。In this scheme, the base station can further improve the accuracy of the determined nonlinear distortion prediction signal by correcting the predicted nonlinear distortion signal according to the nonlinear distortion characteristic parameters of the nonlinear components.
在一种可能的设计中,所述光模块包含:电光转换模块、光电转换模块、第一端口、第二端口、第三端口;所述电光转换模块,用于对所述多路信号进行电光转换处理,所述电光转换模块包含所述非线性元器件;所述光电转换模块,用于对所述光信号进行光电转换处理;所述第一端口,用于接收所述多路信号;所述第二端口,用于将所述光信号发送到所述中心站;所述第三端口,用于将所述电信号发送到所述特征计算模块。In a possible design, the optical module includes: an electro-optical conversion module, a photoelectric conversion module, a first port, a second port, and a third port; Conversion processing, the electro-optical conversion module includes the nonlinear components; the photoelectric conversion module is used to perform photoelectric conversion processing on the optical signal; the first port is used to receive the multi-channel signal; The second port is used to send the optical signal to the central station; the third port is used to send the electrical signal to the feature calculation module.
在该方案中,通过对基站中光模块结构进行改进,增加一个信号传输端口和光电转换模块,能够获取基站发送给中心站的光信号所对应的电信号,从而可以从电信号中获取有用信号经过光模块的非线性元器件后产生的非线性失真信号,并反馈给基站数字链路,便于对非线性成分进行建模和预失真校正。In this scheme, by improving the structure of the optical module in the base station and adding a signal transmission port and a photoelectric conversion module, the electrical signal corresponding to the optical signal sent by the base station to the central station can be obtained, so that useful signals can be obtained from the electrical signal The nonlinear distortion signal generated after passing through the nonlinear components of the optical module is fed back to the digital link of the base station, which is convenient for modeling and pre-distortion correction of nonlinear components.
在一种可能的设计中,所述特征计算模块还包括滤波模块;所述滤波模块,用于对所述电信号进行滤波处理,得到所述目标信号。In a possible design, the feature calculation module further includes a filtering module; the filtering module is configured to filter the electrical signal to obtain the target signal.
在该方案中,基站通过滤波模块对信号进行滤波处理,能够仅保留所需的信号,避免一些无用信号对后续处理过程的干扰,进而提高信号处理的准确度。In this scheme, the base station performs filtering processing on the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and thus improve the accuracy of signal processing.
在一种可能的设计中,所述特征计算模块还包括反馈模块,所述反馈模块用于:对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。In a possible design, the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
在该方案中,基站通过对目标信号和至少一个第二射频链路的信号进行时延校正处理,能够保证根据目标信号确定的非线性失真预测信号与至少一个第二射频链路信号在时间上是对应的,从而避免信号处理过程中由于时延问题所导致的误差。In this solution, the base station can ensure that the non-linear distortion prediction signal determined according to the target signal and the at least one second radio frequency link signal have a time delay correction process on the target signal and at least one second radio frequency link signal are corresponding, so as to avoid errors caused by delay problems in the signal processing process.
在一种可能的设计中,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器;所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理;所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。In a possible design, the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module; A signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator; the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal; the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed; the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment module; the time delay alignment module is configured to remove the time delay according to the time delay after receiving the time delay from the time delay calculation module In the target signal, there is the time-delayed signal with the signal of the set time slot length of the at least one second radio frequency link, and removing the time delay between the signal of the set time slot length of each second radio frequency link and The target signal has the time-delayed signal.
在该方案中,基站可以通过时延计算,确定目标信号和至少一个第二射频链路的信号之间存在的时延,进而根据该时延对所述目标信号和所述至少一个第二射频链路的信号进行时延校正,同时,通过锁数控制方式控制时延计算过程的定时更新,降低了一定的信号处理量。In this solution, the base station can determine the time delay existing between the target signal and the signal of the at least one second radio frequency link through time delay calculation, and then calculate the time delay between the target signal and the at least one second radio frequency link according to the time delay The time delay of the link signal is corrected, and at the same time, the timing update of the time delay calculation process is controlled by the lock number control method, which reduces a certain amount of signal processing.
在一种可能的设计中,所述门限判决模块,还用于:在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;在确定所述相关信号 的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。In a possible design, the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
在该方案中,基站的门限判决模块根据非线性失真信号和至少一个第二射频链路的信号对应的相关信号的相关值的大小,对锁数模块的触发进行控制,能够基于实际场景中的实际信号情况对锁数更新情况进行控制,提高相关控制的准确度和场景适应性。In this scheme, the threshold decision module of the base station controls the triggering of the lock module according to the magnitude of the correlation value of the nonlinear distortion signal and the correlation signal corresponding to the signal of at least one second radio frequency link, which can be based on the actual scene The actual signal situation controls the update situation of the lock number to improve the accuracy of related control and scene adaptability.
在一种可能的设计中,所述第一射频链路根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理时,具体用于:将所述第一射频链路对应频段的信号减去所述非线性失真预测信号,得到对所述第一射频链路对应频段的信号进行预失真处理后的信号。In a possible design, when the first radio frequency link performs predistortion processing on the signal in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, it is specifically used to: The nonlinear distortion prediction signal is subtracted from the signal in the frequency band corresponding to the radio frequency link to obtain a signal after predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link.
第二方面,本申请提供一种基站,包括:多个射频链路、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2;每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号;所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理,得到包含处理后的所述多路信号的光信号;其中,所述光模块中包含非线性元器件,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠,所述光信号中还包含所述非线性失真信号;将所述光信号发送到所述中心站,接收来自所述中心站的目标信号,对所述目标信号进行光电转换处理,并将处理后的所述目标信号发送到所述特征计算模块,其中,所述目标信号包含所述第一射频链路对应的频段的信号;每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块;所述特征计算模块,用于接收来自所述光模块的所述目标信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;所述第一射频链路,还用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。In a second aspect, the present application provides a base station, including: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2; each radio frequency link is used for Receive one signal of the corresponding frequency band through the antenna, and send the one signal to the optical module after performing radio frequency processing on the one signal; The signal is subjected to electro-optical conversion processing to obtain an optical signal including the processed multi-channel signal; wherein, the optical module includes nonlinear components, and there are a first radio frequency link and at least one radio frequency link among the plurality of radio frequency links The second radio frequency link, the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal corresponds to the frequency band of the first radio frequency link There is overlap, and the optical signal also includes the nonlinear distortion signal; sending the optical signal to the central station, receiving the target signal from the central station, and performing photoelectric conversion processing on the target signal, and sending the processed target signal to the feature calculation module, wherein the target signal includes a signal of a frequency band corresponding to the first radio frequency link; each second radio frequency link is also used for receiving After performing radio frequency processing on one signal in the corresponding frequency band, the obtained signal is sent to the feature calculation module; the feature calculation module is used to receive the target signal from the optical module; according to the target signal and the At least one signal of the at least one second radio frequency link calculates a nonlinear distortion prediction signal, and sends the nonlinear distortion prediction signal to the first radio frequency link, where the nonlinear distortion prediction signal is the The first prediction signal of the nonlinear distortion signal; the first radio frequency link is also used to perform pre-distortion processing and radio frequency processing on the signal of the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, And send the processed signal to the optical module.
在该方案中,基站通过将经过非线性元器件后的信号发送到中心站,再接收中心站回环回来的包含有用信号及非线性元器件引起的非线性失真信号的信号,可以基于先前经过其非线性元器件的信号以及该非线性元器件引起的非线性失真信号,对后续信号经过非线性元器件时产生的非线性失真信号进行预测计算,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传输链路上传输的信号进行预失真处理,从而实现对传输链路上信号经过非线性元器件时产生的非线性失真问题的校正,提高进行非线性失真校正的准确度。In this scheme, the base station sends the signal after passing through the nonlinear components to the central station, and then receives the signal containing the useful signal and the nonlinear distortion signal caused by the nonlinear component that is looped back by the central station, which can be based on the previous The signal of the nonlinear component and the nonlinear distortion signal caused by the nonlinear component can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component, which can improve the accuracy of the determined nonlinear distortion prediction signal , and further, the signal transmitted on the transmission link can be pre-distorted according to the determined nonlinear distortion prediction signal, so as to realize the correction of the nonlinear distortion problem generated when the signal on the transmission link passes through nonlinear components, and improve the performance of nonlinear distortion. Accuracy of linear distortion correction.
在一种可能的设计中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者,当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二 射频链路对应频段的截止频率之差。In a possible design, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein: when the multiple radio frequency chains When there is a second radio frequency link in the road, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the frequency corresponding to the second radio frequency link. Twice the cutoff frequency of the frequency band; or, when there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum, the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links The second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
在一种可能的设计中,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;根据所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。In a possible design, the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component nonlinear distortion characteristics; calculate the target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameter The target prediction signal is corrected to obtain the nonlinear distortion prediction signal.
在一种可能的设计中,所述迭代计算模块,在根据所述目标信号计算目标参数时,具体用于:根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;所述迭代计算模块根据所述至少一个第二射频链路的至少一路信号计算目标预测信号时,具体用于:根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。In a possible design, the iterative calculation module, when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
在一种可能的设计中,所述迭代计算模块,在根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号时,具体用于:将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。In a possible design, when the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
在一种可能的设计中,所述特征计算模块还包括滤波模块;所述滤波模块,用于对所述电信号进行滤波处理,得到所述目标信号。In a possible design, the feature calculation module further includes a filtering module; the filtering module is configured to filter the electrical signal to obtain the target signal.
在一种可能的设计中,所述光模块接收来自所述中心站的目标信号,对所述目标信号进行光电转换处理,并将处理后的所述目标信号发送到所述特征计算模块时,具体用于:接收来自所述中心站的下行信号,对所述下行信号进行光电转换处理,并将处理后的所述下行信号发送到所述特征计算模块,其中,所述下行信号中包含所述目标信号及其它待发送给所述基站的信号;所述特征计算模块接收来自所述光模块的所述目标信号时,具体用于:接收来自所述光模块的所述下行信号,并对所述下行信号进行滤波处理,得到所述目标信号。In a possible design, when the optical module receives the target signal from the central station, performs photoelectric conversion processing on the target signal, and sends the processed target signal to the feature calculation module, Specifically used for: receiving a downlink signal from the central station, performing photoelectric conversion processing on the downlink signal, and sending the processed downlink signal to the feature calculation module, wherein the downlink signal includes the The target signal and other signals to be sent to the base station; when the feature calculation module receives the target signal from the optical module, it is specifically used to: receive the downlink signal from the optical module, and The downlink signal is filtered to obtain the target signal.
在该方案中,基站可以从来自中心站的信号中提取出目标信号,便于后续针对目标信号进行处理,并避免其它信号对目标信号的处理过程的干扰,进而提高信号处理的准确度。同时该目标信号是经过中心站回环回来的,因此也可以对中心站中相关的一些非线性元器件的非线性失真问题进行一定程度的校正。In this scheme, the base station can extract the target signal from the signal from the central station, which facilitates subsequent processing of the target signal, and avoids interference from other signals on the processing process of the target signal, thereby improving the accuracy of signal processing. At the same time, the target signal is looped back through the central station, so the nonlinear distortion problems of some related nonlinear components in the central station can also be corrected to a certain extent.
在一种可能的设计中,所述特征计算模块还包括反馈模块,所述反馈模块用于:对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。In a possible design, the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
在一种可能的设计中,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器;所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到 所述时延计算模块,否则,不对所述相关信号进行处理;所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。In a possible design, the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module; A signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator; the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal; the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed; the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment module; the time delay alignment module is configured to remove the time delay according to the time delay after receiving the time delay from the time delay calculation module In the target signal, there is the time-delayed signal with the signal of the set time slot length of the at least one second radio frequency link, and removing the time delay between the signal of the set time slot length of each second radio frequency link and The target signal has the time-delayed signal.
在一种可能的设计中,所述门限判决模块,还用于:在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。In a possible design, the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
在一种可能的设计中,所述第一射频链路根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理时,具体用于:将所述第一射频链路对应频段的信号减去所述非线性失真预测信号,得到对所述第一射频链路对应频段的信号进行预失真处理后的信号。In a possible design, when the first radio frequency link performs predistortion processing on the signal in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, it is specifically used to: The nonlinear distortion prediction signal is subtracted from the signal in the frequency band corresponding to the radio frequency link to obtain a signal after predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link.
第三方面,本申请提供一种中心站,包括:光模块、信号处理模块;所述光模块,用于接收来自基站的光信号后,对所述光信号进行光电转换处理得到电信号,向所述信号处理模块发送所述电信号;其中,所述电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠;所述信号处理模块,用于接收来自所述光模块的所述电信号,从所述电信号中提取所述第一射频链路对应的频段的目标信号,并将所述目标信号发送到所述光模块;所述光模块,还用于对所述目标信号进行电光转换处理,并将处理后的所述目标信号发送到所述基站。In a third aspect, the present application provides a central station, including: an optical module and a signal processing module; the optical module is used to perform photoelectric conversion processing on the optical signal to obtain an electrical signal after receiving an optical signal from a base station, and send the optical signal to the The signal processing module sends the electrical signal; wherein, the electrical signal includes nonlinear distortion signals, multiple signals received by the multiple radio frequency links of the base station through antennas, and the multiple radio frequency links of the multiple radio frequency links The number is greater than or equal to 2, there are a first radio frequency link and at least one second radio frequency link in the plurality of radio frequency links, the base station contains nonlinear components, and the signal of the at least one second radio frequency link The nonlinear distortion signal is generated after passing through the nonlinear components, and the frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link; the signal processing module is used to receive signals from the The electrical signal of the optical module, extracting the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal, and sending the target signal to the optical module; the optical module also uses performing electro-optical conversion processing on the target signal, and sending the processed target signal to the base station.
在该方案中,中心站与基站可以组成环回链路,中心站将来自基站的信号再环回给基站,使得基站可以基于该实际信号对后续信号经过非线性元器件时产生的非线性失真信号进行预测计算,以及根据预测的非线性失真信号对传输链路上传输的信号进行预失真处理,从而提高对基站与中心站之间通信链路的非线性失真校正的准确度,同时在能够实现对基站中非线性失真问题进行校正的同时,也能够实现对中心站中一些非线性失真问题的校正,并提高中心站与基站之间进行通信的准确度。In this scheme, the central station and the base station can form a loopback link, and the central station loops back the signal from the base station to the base station, so that the base station can correct the nonlinear distortion generated when the subsequent signal passes through the nonlinear components based on the actual signal The signal is predicted and calculated, and the signal transmitted on the transmission link is pre-distorted according to the predicted nonlinear distortion signal, so as to improve the accuracy of the nonlinear distortion correction of the communication link between the base station and the central station. While correcting the nonlinear distortion problem in the base station, it can also correct some nonlinear distortion problems in the central station, and improve the accuracy of communication between the central station and the base station.
在一种可能的设计中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者,当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。In a possible design, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein: when the multiple radio frequency chains When there is a second radio frequency link in the road, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the frequency corresponding to the second radio frequency link. Twice the cutoff frequency of the frequency band; or, when there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum, the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links The second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
在一种可能的设计中,所述信号处理模块包含滤波模块,所述滤波模块用于接收来自所述光模块的所述电信号,对所述电信号进行滤波处理,得到所述目标信号;所述光模块对所述目标信号进行电光转换处理,并将处理后的所述目标信号发送到所述基站时,具体用于:对所述目标信号和其它待发送给所述基站的信号进行电光转换处理,得到包含所述目标信号和其它待发送给所述基站的信号的下行信号,并将所述下行信号发送到所述基站。In a possible design, the signal processing module includes a filtering module, and the filtering module is configured to receive the electrical signal from the optical module, filter the electrical signal, and obtain the target signal; When the optical module performs electro-optical conversion processing on the target signal, and sends the processed target signal to the base station, it is specifically used to: perform the target signal and other signals to be sent to the base station Electro-optical conversion processing, obtaining a downlink signal including the target signal and other signals to be sent to the base station, and sending the downlink signal to the base station.
在该方案中,中心站通过滤波模块对信号进行滤波处理,能够仅保留所需的信号,避免一些无用信号对后续处理过程的干扰,进而提高信号处理的准确度。中心站将目标信号与其它信号一波能够发送到基站,可以充分利用已有的传输链路,避免了增加额外的传输链路的开销,提高了资源利用率。In this scheme, the central station filters the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and improve the accuracy of signal processing. The central station can send the target signal and other signals to the base station in one wave, which can make full use of the existing transmission link, avoid the overhead of adding an additional transmission link, and improve resource utilization.
第四方面,本申请提供一种中心站,包括:光模块、信号处理模块、特征计算模块;所述光模块,用于接收来自至少一个基站的光信号,对所述至少一个基站中每个基站的光信号进行光电转换处理,得到每个基站的电信号;其中,任一个基站的电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠;分别将每个基站的电信号发送到所述信号处理模块和所述特征计算模块;所述特征计算模块,用于分别接收来自所述光模块的每个基站的电信号;分别对每个基站的电信号进行特征计算处理,得到每个基站对应的非线性失真预测信号,并分别将每个基站对应的非线性失真预测信号发送到所述信号处理模块;其中,对任一个基站的电信号进行的特征计算处理包含以下步骤:从所述电信号中提取所述第一射频链路对应的频段的目标信号,以及,从所述电信号中分别提取来自所述至少一个第二射频链路的至少一路信号;根据所述目标信号和所述至少一个第二射频链路的至少一路信号计算所述非线性失真预测信号,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;所述信号处理模块,用于分别接收来自所述光模块的每个基站的电信号;对所述至少一个基站的电信号进行合路处理得到目标合路信号;分别接收来自所述特征计算模块的每个基站对应的非线性失真预测信号;依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理。In a fourth aspect, the present application provides a central station, including: an optical module, a signal processing module, and a feature calculation module; the optical module is configured to receive an optical signal from at least one base station, and perform an operation on each of the at least one base station The optical signal of the base station is subjected to photoelectric conversion processing to obtain the electrical signal of each base station; wherein, the electrical signal of any base station includes a nonlinear distortion signal, and multiple signals received by multiple radio frequency links of the base station through the antenna, The number of the plurality of radio frequency links is greater than or equal to 2, there are a first radio frequency link and at least one second radio frequency link in the plurality of radio frequency links, the base station contains nonlinear components, and the at least A signal of a second radio frequency link passes through the nonlinear component to generate the nonlinear distortion signal, and the frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link; The electrical signals of the base stations are sent to the signal processing module and the feature calculation module; the feature calculation module is used to receive the electrical signals from each base station of the optical module respectively; respectively for the electrical signals of each base station Perform feature calculation processing to obtain the nonlinear distortion prediction signal corresponding to each base station, and send the nonlinear distortion prediction signal corresponding to each base station to the signal processing module; wherein, the characteristic of the electrical signal of any one base station The calculation processing includes the following steps: extracting the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal, and respectively extracting at least one channel from the at least one second radio frequency link from the electrical signal signal; calculate the nonlinear distortion prediction signal according to the target signal and at least one signal of the at least one second radio frequency link, wherein the nonlinear distortion prediction signal is the first prediction of the nonlinear distortion signal signal; the signal processing module is configured to respectively receive electrical signals from each base station of the optical module; perform combined processing on the electrical signals of the at least one base station to obtain a target combined signal; respectively receive signals from the features The nonlinear distortion prediction signal corresponding to each base station of the calculation module; sequentially perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station.
在该方案中,中心站对来自至少一个基站的信号进行处理时,可以基于先前经过基站中的非线性元器件的信号以及该非线性元器件引起的非线性失真信号,对后续信号经过该非线性元器件时产生的非线性失真信号进行预测计算,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传来自至少一个基站的信号进行更为准确的失真校正处理。同时,该方案中,中心站可以对来自不同基站的信号进行失真校正处理,并且对基站和中心站的非线性失真问题均可进行有效校正。In this solution, when the central station processes the signal from at least one base station, it can process the subsequent signal through the non-linear component based on the signal that has previously passed through the nonlinear component in the base station and the nonlinear distortion signal caused by the nonlinear component. Prediction and calculation of the nonlinear distortion signal generated by the linear components can improve the accuracy of the determined nonlinear distortion prediction signal, and furthermore, the signal transmitted from at least one base station can be more accurately calculated according to the determined nonlinear distortion prediction signal Distortion correction processing. At the same time, in this scheme, the central station can perform distortion correction processing on the signals from different base stations, and can effectively correct the nonlinear distortion problem of the base station and the central station.
在一种可能的设计中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者,当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第 一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。In a possible design, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein: when the multiple radio frequency chains When there is a second radio frequency link in the road, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the frequency corresponding to the second radio frequency link. Twice the cutoff frequency of the frequency band; or, when there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the start frequency of the frequency band corresponding to the two second radio frequency links sum, the second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the start frequency of the frequency bands corresponding to the two second radio frequency links The second frequency is the difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
在一种可能的设计中,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;根据来自所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。In a possible design, the feature calculation module includes an iterative calculation module, and the iterative calculation module is used to: calculate a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear component The nonlinear distortion characteristic; calculate the target prediction signal according to at least one signal from the at least one second radio frequency link, wherein, the target prediction signal is the second prediction signal of the nonlinear distortion signal; according to the target parameters to modify the target prediction signal to obtain the nonlinear distortion prediction signal.
在该方案中,中心站基于实际经过非线性元器件的信号以及该信号经过非线性元器件后实际产生的非线性失真信号,计算非线性元器件的非线性失真特性参数,能够提高确定非线性元器件的非线性失真特性的准确度,进而提高基于非线性元器件的非线性失真特性参数对目标预测信号进行校正的准确度。In this scheme, the central station calculates the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear components and the nonlinear distortion signal actually generated after the signal passes through the nonlinear components, which can improve the determination of nonlinear The accuracy of the nonlinear distortion characteristic of the component is improved, and then the accuracy of correcting the target prediction signal based on the nonlinear distortion characteristic parameter of the nonlinear component is improved.
在一种可能的设计中,所述迭代计算模块,在根据所述目标信号计算目标参数时,具体用于:根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;所述迭代计算模块根据所述至少一个第二射频链路的至少一路信号计算目标预测信号时,具体用于:根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。In a possible design, the iterative calculation module, when calculating the target parameter according to the target signal, is specifically configured to: calculate the target parameter according to the set first calculation model and the target signal, wherein , the first calculation model is used to represent one of the multiple signals input to the nonlinear component, the nonlinear distortion signal output by the nonlinear component and the same frequency band as the one signal and the nonlinear The correspondence between the nonlinear distortion characteristic parameters of components; when the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for: according to the set second calculation model and at least one signal of the at least one second radio frequency link, and calculate the target prediction signal, wherein the second calculation model is used to represent the at least one signal passing through the nonlinear component and the at least one signal passing through Correspondence between nonlinear distortion signals generated by the nonlinear components.
在该方案中,中心站通过利用有用信号与失真信号进行建模计算,对有用信号经过非线性元器件后产生的非线性失真信号进行预测,能够通过计算模型简便、快速、准确的得到所需计算的目标预测信号。In this scheme, the central station predicts the nonlinear distortion signal generated by the useful signal through the nonlinear components by using the useful signal and the distorted signal for modeling calculation, and can obtain the required information easily, quickly and accurately through the calculation model. Calculated target prediction signal.
在一种可能的设计中,所述迭代计算模块,在根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号时,具体用于:将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。In a possible design, when the iterative calculation module corrects the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, it is specifically configured to: combine the target parameter with the The target prediction signal is multiplied to obtain the nonlinear distortion prediction signal.
在该方案中,中心站通过根据非线性元器件的非线性失真特性参数对预测的非线性失真信号进行校正,能够进一步提高确定的非线性失真预测信号的准确度。In this solution, the central station can further improve the accuracy of the determined nonlinear distortion prediction signal by correcting the predicted nonlinear distortion signal according to the nonlinear distortion characteristic parameters of the nonlinear components.
在一种可能的设计中,所述特征计算模块还包括滤波模块;所述滤波模块,用于对所述合路电信号进行滤波处理,得到所述目标信号。In a possible design, the feature calculation module further includes a filtering module; the filtering module is configured to filter the combined electrical signal to obtain the target signal.
在该方案中,中心站通过滤波模块对信号进行滤波处理,能够仅保留所需的信号,避免一些无用信号对后续处理过程的干扰,进而提高信号处理的准确度。In this scheme, the central station filters the signal through the filtering module, which can only retain the required signal, avoid some unnecessary signals from interfering with the subsequent processing process, and improve the accuracy of signal processing.
在一种可能的设计中,所述特征计算模块还包括反馈模块,所述反馈模块用于:对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。In a possible design, the feature calculation module further includes a feedback module, configured to: perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link, Obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
在该方案中,中心站通过对目标信号和至少一个第二射频链路的信号进行时延校正处理,能够保证根据目标信号确定的非线性失真预测信号与至少一个第二射频链路信号在时间上是对应的,从而避免信号处理过程中由于时延问题所导致的误差。In this solution, the central station can ensure that the non-linear distortion prediction signal determined according to the target signal and the at least one second radio frequency link signal are within a time delay correction process for the target signal and at least one second radio frequency link signal The above is corresponding, so as to avoid the error caused by the delay problem in the signal processing process.
在一种可能的设计中,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;所述锁数模块,用于分别锁存来自所述至少一个第二射频链路 的设定时隙长度的信号,并将锁存的信号发送到所述相关器;所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理;所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。In a possible design, the feedback module includes: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module; A signal of the set time slot length of the second radio frequency link, and the latched signal is sent to the correlator; the correlator is used to perform the target signal and the signal from the lock module Correlation processing, obtaining a correlation signal, and sending the correlation signal to the threshold judgment module, wherein the correlation signal is a nonlinear signal; the threshold judgment module is used to judge the correlation of the received correlation signal Whether the value is greater than or equal to the set value, if so, then the relevant signal is sent to the time delay calculation module, otherwise, the relevant signal is not processed; the time delay calculation module is used to When the correlation signal of the threshold judgment module is used, the time delay between the signal of the first radio frequency link and the signal of the set time slot length of the at least one second radio frequency link is calculated according to the correlation signal, and sending the time delay to the time delay alignment module; the time delay alignment module is configured to remove the time delay according to the time delay after receiving the time delay from the time delay calculation module In the target signal, there is the time-delayed signal with the signal of the set time slot length of the at least one second radio frequency link, and removing the time delay between the signal of the set time slot length of each second radio frequency link and The target signal has the time-delayed signal.
在该方案中,中心站可以通过时延计算,确定目标信号和至少一个第二射频链路的信号之间存在的时延,进而根据该时延对所述目标信号和所述至少一个第二射频链路的信号进行时延校正,同时,通过锁数控制方式控制时延计算过程的定时更新,降低了一定的信号处理量。In this scheme, the central station can determine the time delay existing between the target signal and the signal of the at least one second radio frequency link through time delay calculation, and then calculate the time delay between the target signal and the at least one second radio frequency link according to the time delay. The delay is corrected for the signal of the radio frequency link, and at the same time, the timing update of the delay calculation process is controlled by the lock number control method, which reduces a certain amount of signal processing.
在一种可能的设计中,所述门限判决模块,还用于:在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。In a possible design, the threshold decision module is further configured to: when it is determined that the correlation value of the correlation signal is greater than or equal to the set value, instruct the lock module to respectively latch the A signal of a set time slot length of the second radio frequency link, and use the currently locked signal to replace the previously latched signal; when it is determined that the correlation value of the related signal is less than the set value, indicate the The locking module stops locking the signal of the set time slot length from the at least one second radio frequency link.
在该方案中,中心站的门限判决模块根据非线性失真信号和至少一个第二射频链路的信号对应的相关信号的相关值的大小,对锁数模块的触发进行控制,能够基于实际场景中的实际信号情况对锁数更新情况进行控制,提高相关控制的准确度和场景适应性。In this scheme, the threshold decision module of the central station controls the triggering of the lock module according to the magnitude of the correlation value of the nonlinear distortion signal and the correlation signal corresponding to the signal of at least one second radio frequency link, which can be based on the actual scene According to the actual signal situation, the update situation of the number of locks is controlled, and the accuracy of related control and scene adaptability are improved.
在一种可能的设计中,所述至少一个基站中包含第一基站与第二基站,所述信号处理模块,在依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理时,具体用于:根据所述第一基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理,得到第一目标合路信号;根据所述第二基站对应的非线性失真预测信号对所述第一目标合路信号进行失真校正处理,得到第二目标合路信号。In a possible design, the at least one base station includes a first base station and a second base station, and the signal processing module sequentially processes the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station. During the distortion correction processing, it is specifically used to: perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal; The nonlinear distortion prediction signal performs distortion correction processing on the first target combined signal to obtain a second target combined signal.
在一种可能的设计中,所述信号处理模块,在根据所述第一基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理,得到第一目标合路信号时,具体用于:将所述目标合路信号减去所述第一基站对应的非线性失真预测信号,得到所述第一目标合路信号。In a possible design, when the signal processing module performs distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal, specifically It is used for: subtracting the nonlinear distortion prediction signal corresponding to the first base station from the target combined signal to obtain the first target combined signal.
第五方面,本申请提供一种非线性信号处理方法,应用于基站或中心站,所述方法包括:根据目标信号计算目标参数,其中,所述目标信号包含:经过非线性元器件的第一信号、至少一个第二信号经过非线性元器件后生成的非线性失真信号,所述非线性失真信号的频段与所述第一信号的频段有交叠,所述目标参数用于表征所述非线性元器件的非线性失真特性;根据所述至少一个第二信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的预测信号;根据所述目标参数对所述目标预测信号进行修正,得到非线性失真预测信号;其中,所述非线性失真预测信号为修正后的、所述非线性失真信号的预测信号。In a fifth aspect, the present application provides a nonlinear signal processing method, which is applied to a base station or a central station. The method includes: calculating target parameters according to the target signal, wherein the target signal includes: a first signal, at least one second signal is a nonlinear distortion signal generated after passing through a nonlinear component, the frequency band of the nonlinear distortion signal overlaps with the frequency band of the first signal, and the target parameter is used to characterize the nonlinear distortion signal Non-linear distortion characteristics of linear components; calculating a target prediction signal according to the at least one second signal, wherein the target prediction signal is a prediction signal of the nonlinear distortion signal; predicting the target according to the target parameter The signal is corrected to obtain a nonlinear distortion prediction signal; wherein, the nonlinear distortion prediction signal is a modified prediction signal of the nonlinear distortion signal.
在一种可能的设计中,根据目标信号计算目标参数,包括:根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系。In a possible design, calculating the target parameter according to the target signal includes: calculating the target parameter according to the set first calculation model and the target signal, wherein the first calculation model is used to represent the input non- Correspondence between one signal among the multiple signals of the linear component, the nonlinear distortion signal output by the nonlinear component with the same frequency band as the one signal, and the nonlinear distortion characteristic parameters of the nonlinear component relation.
在一种可能的设计中,根据所述至少一个第二信号计算目标预测信号,包括:根据设定的第二计算模型及所述至少一个第二信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。In a possible design, calculating the target prediction signal according to the at least one second signal includes: calculating the target prediction signal according to a set second calculation model and the at least one second signal, wherein the The second calculation model is used to represent the corresponding relationship between at least one signal passing through the nonlinear component and the nonlinear distortion signal generated after the at least one signal passes through the nonlinear component.
在一种可能的设计中,根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号,包括:将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。In a possible design, correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal includes: multiplying the target parameter by the target prediction signal to obtain the Nonlinear distortion prediction signal.
第六方面,本申请提供一种装置,所述装置包括存储器和处理器;所述存储器用于存储计算机程序;所述处理器用于执行所述存储器中存储的计算机程序,实现上述第五方面或第五方面的任一可能的设计所描述的方法。In a sixth aspect, the present application provides a device, the device includes a memory and a processor; the memory is used to store computer programs; the processor is used to execute the computer programs stored in the memory, to achieve the fifth aspect or Any possible design of the fifth aspect describes the method.
第七方面,本申请提供一种通信系统,所述通信系统包括:上述第一方面或第一方面的任一可能的设计所描述的基站,或者上述第二方面或第二方面的任一可能的设计所描述的基站,以及上述第三方面或第三方面的任一可能的设计所描述的中心站,或者上述第四方面或第四方面的任一可能的设计所描述的中心站。In a seventh aspect, the present application provides a communication system, the communication system comprising: the base station described in the above first aspect or any possible design of the first aspect, or the above second aspect or any possible design of the second aspect The base station described in the design, and the central station described in the third aspect or any possible design of the third aspect, or the central station described in the fourth aspect or any possible design of the fourth aspect.
上述第二方面的有益效果,请参见上述第一方面的相关有益效果的描述,上述第五方面到第七方面的有益效果,请参见上述第一到第四方面的有益效果的描述,这里不再重复赘述。For the above-mentioned beneficial effects of the second aspect, please refer to the description of the relevant beneficial effects of the above-mentioned first aspect, and for the above-mentioned beneficial effects of the fifth to seventh aspects, please refer to the description of the above-mentioned beneficial effects of the first to fourth aspects. Repeat it again.
附图说明Description of drawings
图1为一种ROF系统的架构示意图;FIG. 1 is a schematic diagram of the architecture of an ROF system;
图2为一种ROF系统中射频信号传输的示意图;Fig. 2 is a schematic diagram of radio frequency signal transmission in an ROF system;
图3为ROF系统中产生IMD2的三种场景的示例图;Fig. 3 is the example diagram of three kinds of scenes that produce IMD2 in ROF system;
图4a为一种模拟预失真非线性校正链路的结构示意图;Fig. 4a is a structural schematic diagram of an analog predistortion nonlinear correction link;
图4b为一种基于推挽结构联合自适应后补偿的非线性失真校正链路的结构示意图;Fig. 4b is a structural schematic diagram of a nonlinear distortion correction link based on a push-pull structure joint adaptive post-compensation;
图5为本申请实施例提供的一种ROF系统的架构示意图;FIG. 5 is a schematic structural diagram of an ROF system provided in an embodiment of the present application;
图6为本申请实施例提供的一种基站的示意图;FIG. 6 is a schematic diagram of a base station provided in an embodiment of the present application;
图7为本申请实施例提供的一种基站中的反馈模块的示意图;FIG. 7 is a schematic diagram of a feedback module in a base station provided by an embodiment of the present application;
图8为本申请实施例提供的一种ROF系统的示意图;FIG. 8 is a schematic diagram of an ROF system provided in an embodiment of the present application;
图9为本申请实施例提供的一种ROF系统的示意图;FIG. 9 is a schematic diagram of an ROF system provided by an embodiment of the present application;
图10为本申请实施例提供的一种光模块结构的对比示意图;FIG. 10 is a comparative schematic diagram of an optical module structure provided by an embodiment of the present application;
图11为本申请实施例提供的一种基站结构的精简结构示意图;FIG. 11 is a simplified structural schematic diagram of a base station structure provided by an embodiment of the present application;
图12为本申请实施例提供的一种基站和中心站的示意图;FIG. 12 is a schematic diagram of a base station and a central station provided in an embodiment of the present application;
图13为本申请实施例提供的一种ROF系统的示意图;FIG. 13 is a schematic diagram of an ROF system provided by an embodiment of the present application;
图14为本申请实施例提供的一种中心站的示意图;FIG. 14 is a schematic diagram of a central station provided by an embodiment of the present application;
图15为本申请实施例提供的一种ROF系统的示意图;FIG. 15 is a schematic diagram of an ROF system provided by an embodiment of the present application;
图16为本申请实施例提供的一种非线性信号处理方法的示意图。FIG. 16 is a schematic diagram of a nonlinear signal processing method provided by an embodiment of the present application.
具体实施方式Detailed ways
为了使本申请实施例的目的、技术方案和优点更加清楚,下面将结合附图对本申请实施例作进一步地详细描述。其中,在本申请实施例的描述中,以下,术语“第一”、“第二”仅用于描述目的,而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此,限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个该特征。In order to make the purpose, technical solutions, and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings. Among them, in the description of the embodiments of the present application, the terms "first" and "second" are used for description purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features . Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features.
为了便于理解,示例性的给出了与本申请相关概念的说明以供参考。In order to facilitate understanding, descriptions of concepts related to the present application are provided as examples for reference.
1)非线性失真,指元器件(或电子元器件)的输出信号与输入信号不成线性关系,是由元器件的非线性特性所引起的。非线性失真表现为相同或不同频率的多个信号通过非线性元器件(例如激光二极管、光电二极管、放大器等)后,会产生新的谐波成分或新的频率分量的干扰信号。1) Nonlinear distortion, which means that the output signal of a component (or electronic component) does not have a linear relationship with the input signal, which is caused by the nonlinear characteristics of the component. Nonlinear distortion is manifested as multiple signals of the same or different frequencies passing through nonlinear components (such as laser diodes, photodiodes, amplifiers, etc.), generating new harmonic components or interference signals of new frequency components.
非线性失真包括谐波失真(harmonic distortion,HD)、互调失真(intermodulation distortion,IMD)、交调失真等。其中,互调失真是由非线性元器件所引入的一种输入信号的频率成分之和或者频率成分之差的失真。当信号进入非线性元器件时,非线性元器件的非线性特性会引起信号之间的相互(调制)作用,产生在原信号中所没有的额外信号,这种额外信号可能会对原信号中的部分信号造成干扰。Nonlinear distortion includes harmonic distortion (harmonic distortion, HD), intermodulation distortion (intermodulation distortion, IMD), and intermodulation distortion. Wherein, the intermodulation distortion is the distortion of the sum of the frequency components or the difference of the frequency components of an input signal introduced by the nonlinear components. When the signal enters the nonlinear components, the nonlinear characteristics of the nonlinear components will cause the mutual (modulation) effect between the signals, and generate additional signals that are not in the original signal. This additional signal may affect the original signal. Some signals are causing interference.
在本申请实施例中,非线性元器件包括但不限于光电转换器(electronic-optical convertor,O-E)、电光转换器、放大器等。示例性的,所述光电转换器可以为光电二极管(photo-diode,PD);所述电光转换器可以为激光二极管(laser diode,LD),所述放大器可以为低噪声放大器(low noise amplifier,LNA)。In the embodiment of the present application, the nonlinear components include, but are not limited to, an optoelectronic converter (electronic-optical converter, O-E), an electro-optical converter, an amplifier, and the like. Exemplarily, the photoelectric converter can be a photodiode (photo-diode, PD); the electro-optical converter can be a laser diode (laser diode, LD), and the amplifier can be a low noise amplifier (low noise amplifier, LNA).
2)预失真,指在信号通过非线性元器件之前,对信号进行一个特性与非线性元器件引起的非线性失真特性相反的预处理过程,使其与信号通过非线性元器件时产生的非线性失真进行互相补偿,从而减轻或避免非线性元器件引起的非线性失真。2) Pre-distortion means that before the signal passes through the nonlinear components, the signal is subjected to a preprocessing process whose characteristics are opposite to the nonlinear distortion characteristics caused by the nonlinear components, so that it is different from the non-linear distortion generated when the signal passes through the nonlinear components. The linear distortion compensates each other, so as to reduce or avoid the nonlinear distortion caused by the nonlinear components.
应理解,本申请实施例中“至少一个”是指一个或者多个,“多个”是指两个或两个以上。“和/或”,描述关联对象的关联关系,表示可以存在三种关系,例如,A和/或B,可以表示:单独存在A,同时存在A和B,单独存在B的情况,其中A、B可以是单数或者复数。字符“/”一般表示前后关联对象是一种“或”的关系。“以下至少一(项)个”或其类似表达,是指的这些项中的任意组合,包括单项(个)或复数项(个)的任意组合。例如,a、b或c中的至少一项(个),可以表示:a,b,c,a和b,a和c,b和c,或a、b和c,其中a、b、c可以是单个,也可以是多个。It should be understood that "at least one" in the embodiments of the present application refers to one or more, and "multiple" refers to two or more. "And/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A, B can be singular or plural. The character "/" generally indicates that the contextual objects are an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single item(s) or plural item(s). For example, at least one item (unit) of a, b or c can represent: a, b, c, a and b, a and c, b and c, or a, b and c, wherein a, b, c Can be single or multiple.
当前,随着第五代移动通信(the 5th-generation wireless communication,5G)技术的推广和第六代移动通信(the 6th-generation wireless communication,6G)技术的研究开展,移动网络急需支持超大规模无线接入和超高速数据传输的技术。ROF(radio over fiber,光载无线通信)技术就是应高速大容量无线通信需求发展起来的。Currently, with the promotion of the 5th-generation wireless communication (5G) technology and the research of the 6th-generation wireless communication (6G) technology, the mobile network urgently needs to support ultra-large-scale wireless Technology for access and ultra-high-speed data transmission. ROF (radio over fiber, wireless communication over optical) technology was developed in response to the demand for high-speed and large-capacity wireless communication.
ROF是一种将光纤通信和无线通信结合起来的无线接入技术,ROF系统中一般包含中心站(center station,CS)和基站(base station,BS),二者之间通过光纤进行通信。其中,中心站/基站可以把射频电信号调制为光信号后与对端进行信号传输,并可以通过载波复用的方式实现多个频段的无线载波信号的同时超宽带传输,有助于降低通信系统成本、功耗以及复杂度等。ROF在移动无线通信系统、有线电视(cable television,CATV)系统以 及卫星通信系统等领域中应用广泛。ROF is a wireless access technology that combines optical fiber communication and wireless communication. The ROF system generally includes a center station (center station, CS) and a base station (base station, BS), which communicate through optical fibers. Among them, the central station/base station can modulate the radio frequency electrical signal into an optical signal and then transmit the signal to the opposite end, and can realize the simultaneous ultra-wideband transmission of wireless carrier signals in multiple frequency bands by means of carrier multiplexing, which helps to reduce communication costs. System cost, power consumption and complexity etc. ROF is widely used in mobile wireless communication systems, cable television (CATV) systems, and satellite communication systems.
图1示出了一种ROF系统的架构示意图。如图1中所示,ROF系统中可以包含中心站、基站,还可以包括用户设备。Fig. 1 shows a schematic diagram of the architecture of an ROF system. As shown in FIG. 1 , the ROF system may include a central station, a base station, and may also include user equipment.
本申请实施例中,基站也可以称为头端、模拟头端、远端射频单元(remote radio unit,RRU)。中心站也可以称为母端、模拟母端、基带单元(baseband unit,BBU)。In the embodiment of the present application, the base station may also be called a head end, an analog head end, or a remote radio unit (remote radio unit, RRU). The central station may also be called a mother end, an analog mother end, or a baseband unit (BBU).
参照图1,在ROF系统中,以通信下行流程为例,中心站可以将射频电信号(也可以称为电磁波/微波)调制到激光上,之后调制后的光波可以通过光纤链路传输到基站,基站接收到来自中心站的光波信号后,通过光电转换将光波信号解调得到电信号,再通过天线发射给用户设备,以供用户设备使用。通信下行流程与上述通信上行流程相反,此处不再赘述。Referring to Figure 1, in the ROF system, taking the communication downlink process as an example, the central station can modulate the radio frequency electrical signal (also called electromagnetic wave/microwave) to the laser, and then the modulated light wave can be transmitted to the base station through an optical fiber link After the base station receives the light wave signal from the central station, it demodulates the light wave signal through photoelectric conversion to obtain an electrical signal, and then transmits it to the user equipment through the antenna for use by the user equipment. The communication downlink process is opposite to the above communication uplink process, and will not be repeated here.
ROF系统中以光纤或光电混合缆等光载链路作为中心站与基站之间的传输链路,可以直接利用光载波来传输射频信号,从而降低信号传输损耗。其中,上述光载链路仅起到信号传输的作用,关于信号的交换、控制以及信号的再生等处理均可以集中在中心站,基站可以实现信号的光电格式转换,这样可以把复杂的、高成本的装置集中到中心站,使得多个基站可以共享中心站的资源,从而减少基站的功耗和成本。In the ROF system, the optical carrier link such as optical fiber or optical hybrid cable is used as the transmission link between the central station and the base station, and the optical carrier can be directly used to transmit radio frequency signals, thereby reducing signal transmission loss. Among them, the above-mentioned optical link only plays the role of signal transmission, and the processing of signal exchange, control and signal regeneration can be concentrated in the central station, and the base station can realize the optical-electrical format conversion of the signal, so that complex and high-level The cost devices are concentrated in the central station, so that multiple base stations can share the resources of the central station, thereby reducing the power consumption and cost of the base station.
ROF系统在无线通信中的优势主要包括如下几点:ROF系统采用光传输技术进行信号传输,相比电传输技术具有更低的传输损耗(通常光纤衰减小于0.4dB/km);ROF系统支持超宽带信号承载传输能力(传输频率可达0~40GHz);ROF系统易于安装和维护(光纤重量约为同轴电缆的十分之一,且光纤成本较低),ROF系统保密性强(传输的信号由光纤承载,可抵抗电磁干扰,增强安全性和保密性)。The advantages of ROF system in wireless communication mainly include the following points: ROF system uses optical transmission technology for signal transmission, which has lower transmission loss than electrical transmission technology (usually the fiber attenuation is less than 0.4dB/km); ROF system supports ultra- Broadband signal bearing and transmission capability (transmission frequency can reach 0-40GHz); ROF system is easy to install and maintain (the weight of optical fiber is about one tenth of that of coaxial cable, and the cost of optical fiber is low), and ROF system has strong confidentiality (transmission The signal is carried by optical fiber, which can resist electromagnetic interference and enhance safety and confidentiality).
在具有较明显优势的同时,ROF系统也存在一些缺点。例如,ROF系统是模拟传输系统,因此容易出现信号损伤(如噪声和失真);光载链路中可能会产生诸如色散之类的非线性效应;ROF系统中需要电-光(electrical–optical,E-O)和光电(optical-electrical,O-E)转换,增加了处理的复杂度,提高了ROF系统的部署成本;ROF系统中一些非线性元器件会引起信号的非线性失真问题,降低ROF系统的性能。While having obvious advantages, the ROF system also has some disadvantages. For example, the ROF system is an analog transmission system, so it is prone to signal impairments (such as noise and distortion); nonlinear effects such as dispersion may occur in optical links; electrical–optical (electrical–optical, E-O) and optical-electrical (O-E) conversion increase the complexity of processing and increase the deployment cost of the ROF system; some nonlinear components in the ROF system will cause nonlinear distortion of the signal and reduce the performance of the ROF system .
图2为一种ROF系统中射频(radio frequency,RF)信号传输的示意图。如图2中所示,在ROF系统的射频信号传输中,一些非线性元器件例如激光二极管、光电二极管、射频放大器等可以用于实现信号处理和传输等功能。但是,这些非线性元器件在处理和传输信号的过程中可能会引起信号的非线性失真问题,影响信号的准确处理,尤其在多用户的情况下,会严重降低ROF系统的性能。FIG. 2 is a schematic diagram of radio frequency (radio frequency, RF) signal transmission in an ROF system. As shown in Figure 2, in the radio frequency signal transmission of the ROF system, some nonlinear components such as laser diodes, photodiodes, radio frequency amplifiers, etc. can be used to implement functions such as signal processing and transmission. However, these nonlinear components may cause nonlinear distortion of the signal during signal processing and transmission, affecting the accurate processing of the signal, especially in the case of multiple users, which will seriously reduce the performance of the ROF system.
ROF系统中常见的非线性失真问题包括谐波失真、互调失真、交调失真等问题,下面以二阶互调失真(IMD2)为例进行简单说明。其中,IMD2可以是两种不同频段的信号经过非线性元器件后产生的,也可以是同一频段的信号经过非线性元器件后生成的。图3为ROF系统中产生IMD2的三种场景的示例图。Common nonlinear distortion problems in ROF systems include harmonic distortion, intermodulation distortion, and intermodulation distortion. The following takes second-order intermodulation distortion (IMD2) as an example for a brief description. Wherein, IMD2 may be generated after signals of two different frequency bands pass through nonlinear components, or may be generated after signals of the same frequency band pass through nonlinear components. Fig. 3 is an example diagram of three scenarios in which IMD2 is generated in the ROF system.
示例性的,在第一种可能的场景中,如图3中所示的场景1,IMD2为经过非线性元器件的两种频段的信号频率成分的和的失真。例如,信号S F1的中心频率为F1,信号S F1的信号频率范围为频段F11~F12,信号S F2的中心频率为F2,信号S F2的信号频率范围为频段F21~F22,信号S F1与信号S F2同时经过非线性元器件后可能会产生IMD2信号,该IMD2信号的频率范围在(F11+F21)~(F12+F22)之间,则信号频率范围与该IMD2信号的频率范围有交叠的信号S F3与信号S F1、信号S F2同时经过非线性元器件时,信号S F1与信号 S F2经过非线性元器件后产生的IMD2信号会击中信号S F3,对信号S F3造成干扰,影响后续对信号S F3的正常处理。 Exemplarily, in the first possible scenario, such as scenario 1 shown in FIG. 3 , IMD2 is the distortion of the sum of signal frequency components in two frequency bands passing through the nonlinear component. For example, the center frequency of the signal S F1 is F1, the signal frequency range of the signal S F1 is the frequency band F11-F12, the center frequency of the signal S F2 is F2, the signal frequency range of the signal S F2 is the frequency band F21-F22, the signal S F1 and The IMD2 signal may be generated after the signal S F2 passes through the nonlinear components at the same time. The frequency range of the IMD2 signal is between (F11+F21)~(F12+F22). When the overlapping signal S F3 , signal S F1 , and signal S F2 pass through the nonlinear components at the same time, the IMD2 signal generated after the signal S F1 and the signal S F2 pass through the nonlinear components will hit the signal S F3 , causing damage to the signal S F3 Interference affects subsequent normal processing of the signal S F3 .
在第二种可能的场景中,如图3中所示的场景2,IMD2为经过非线性元器件的两种频段的信号频率成分的差的失真。例如,上述信号S F1与信号S F2同时经过非线性元器件后产生的IMD2信号的频率范围在(F11-F21)~(F12-F22)之间,该IMD2信号的频段与上述信号S F3的频段有交叠时,也会击中信号S F3,对信号S F3造成干扰,影响后续对信号S F3的正常处理。 In the second possible scenario, such as scenario 2 shown in FIG. 3 , IMD2 is the distortion of the difference between the signal frequency components of the two frequency bands passing through the nonlinear component. For example, the frequency range of the IMD2 signal generated by the above-mentioned signal S F1 and the signal S F2 passing through the nonlinear components at the same time is between (F11-F21) ~ (F12-F22), and the frequency band of the IMD2 signal is the same as that of the above-mentioned signal S F3 When the frequency bands overlap, they will also hit the signal S F3 , causing interference to the signal S F3 and affecting subsequent normal processing of the signal S F3 .
在第三种可能的场景中,如图3中所示的场景3,IMD2为经过非线性元器件的一种频段的信号频率成分的和的失真。例如,在上述信号S F1与信号S F2相同例如只有信号S F1时,信号S F1经过非线性元器件后产生的IMD2信号的频率范围为频段2F11~2F12,该IMD2信号的频段与上述信号S F3的频段有交叠时,也会击中信号S F3,对信号S F3造成干扰,影响后续对信号S F3的正常处理。 In the third possible scenario, such as scenario 3 shown in FIG. 3 , IMD2 is the distortion of the sum of frequency components of signals in a frequency band passing through nonlinear components. For example, when the above-mentioned signal S F1 is the same as the signal S F2, for example, only the signal S F1 , the frequency range of the IMD2 signal generated by the signal S F1 after passing through the nonlinear components is the frequency range 2F11-2F12, and the frequency range of the IMD2 signal is the same as the above-mentioned signal S When the frequency bands of F3 overlap, they will also hit the signal S F3 , causing interference to the signal S F3 and affecting subsequent normal processing of the signal S F3 .
上述三种场景下的二阶互调失真信号都会影响对有用信号的正常处理,从而会影响ROF系统的性能。The second-order intermodulation distortion signals in the above three scenarios will affect the normal processing of useful signals, thereby affecting the performance of the ROF system.
当前为了解决ROF系统中非线性元器件引起的非线性失真问题,一种方案是可以通过模拟预失真方式对ROF系统中的非线性失真进行校正,还有一种方案是可以基于推挽结构联合自适应后补偿的方法对ROF系统中的非线性失真进行校正。In order to solve the problem of nonlinear distortion caused by nonlinear components in the ROF system, one solution is to correct the nonlinear distortion in the ROF system through analog pre-distortion, and another solution is to combine the push-pull structure with the automatic The post-adaptive compensation method corrects the nonlinear distortion in the ROF system.
图4a为一种模拟预失真非线性校正链路的结构示意图。如图4a所示,在通过模拟预失真方式对ROF系统中的非线性失真进行校正的方案中,从非线性失真信号生成单元到第二相位调整单元的多个功能单元构成了一个模拟预失真校正链路。该模拟预失真校正链路可以利用预先设计好的固定参数和元器件特性的模拟元器件搭建得到,实现模拟预失真功能,可以一定程度上针对性的改善一些非线性失真问题。但是,该方案中,由于预失真校正链路一般比较固定,因此只能针对性的校正某类非线性元器件引起的非线性失真,而对于不同非线性器件引起的非线性失真无法实现自适应的迭代校正处理,使用范围比较局限。同时,固定的模拟预失真校正链路对非线性失真信号的拟合能力也相对有限,导致模拟预失真校正链路的校正性能受限。此外,模拟预失真校正链路无法自适应拟合温度变化造成的非线性影响。Fig. 4a is a schematic structural diagram of an analog predistortion nonlinear correction link. As shown in Figure 4a, in the scheme of correcting the nonlinear distortion in the ROF system by means of analog predistortion, multiple functional units from the nonlinear distortion signal generation unit to the second phase adjustment unit constitute an analog predistortion Correct the link. The analog predistortion correction link can be built by using pre-designed analog components with fixed parameters and component characteristics to realize the analog predistortion function, which can improve some nonlinear distortion problems to a certain extent. However, in this solution, since the pre-distortion correction link is generally fixed, it can only correct the nonlinear distortion caused by certain types of nonlinear components in a targeted manner, and cannot achieve self-adaptation for the nonlinear distortion caused by different nonlinear components. Iterative correction processing, the scope of use is relatively limited. At the same time, the fitting capability of the fixed analog pre-distortion correction link to the nonlinear distortion signal is relatively limited, resulting in limited correction performance of the analog pre-distortion correction link. In addition, the analog predistortion correction chain cannot adaptively fit the nonlinear effects caused by temperature changes.
图4b为一种基于推挽结构联合自适应后补偿的非线性失真校正链路的结构示意图。如图4b所示,在基于推挽结构联合自适应后补偿的方法对ROF系统中的非线性失真进行校正方案中,通过推挽结构使得系统中上下行链路的相位差维持在180度附近,接收端利用平衡探测以抑制所有偶数阶非线性失真,之后采用自适应补偿算法抑制主要的奇数阶非线性失真。该方案能够同时自适应地抑制由于系统中非线性元器件的非线性产生的偶数阶失真(如二阶互调失真IMD2和二阶谐波失真HD2)、奇数阶失真(如三阶交调失真IMD3、三阶叉调失真XMD3等)。但是,该方案的校正链路中的LD和PD均需要部署两套,存在系统的部署成本高、元器件部署面积大的问题。Fig. 4b is a schematic structural diagram of a nonlinear distortion correction link based on a push-pull structure combined with adaptive post-compensation. As shown in Figure 4b, in the method of correcting the nonlinear distortion in the ROF system based on the push-pull structure joint adaptive post-compensation method, the phase difference between the uplink and downlink in the system is maintained at around 180 degrees through the push-pull structure , the receiver uses balanced detection to suppress all even-order nonlinear distortions, and then uses an adaptive compensation algorithm to suppress the main odd-order nonlinear distortions. The scheme can adaptively suppress the even-order distortion (such as second-order intermodulation distortion IMD2 and second-order harmonic distortion HD2) and odd-order distortion (such as third-order intermodulation distortion) generated by the nonlinearity of nonlinear components in the system simultaneously. IMD3, XMD3, etc.). However, two sets of LDs and PDs in the correction link of this solution need to be deployed, which has the problems of high system deployment cost and large deployment area of components.
上述进行非线性失真校正的方案存在非线性失真校正性能较低、成本较高等问题。鉴于此,本申请实施例提供一种基站、中心站及非线性信号处理方法,用以以较低的部署成本实现非线性失真校正系统的部署,同时提高计算非线性失真信号的准确度,从而进一步提高根据确定的非线性失真信号对非线性失真进行校正或补偿的性能。The above solution for nonlinear distortion correction has problems such as low nonlinear distortion correction performance and high cost. In view of this, an embodiment of the present application provides a base station, a central station, and a nonlinear signal processing method to implement the deployment of a nonlinear distortion correction system at a lower deployment cost, and at the same time improve the accuracy of calculating the nonlinear distortion signal, thereby The performance of correcting or compensating the nonlinear distortion according to the determined nonlinear distortion signal is further improved.
本申请以下实施例中以解决ROF系统的二阶互调失真问题为例,对本申请实施例提供的基站、中心站及非线性信号处理方法进行详细介绍。In the following embodiments of the present application, taking the solution to the second-order intermodulation distortion problem of the ROF system as an example, the base station, the central station and the nonlinear signal processing method provided in the embodiments of the present application are introduced in detail.
应理解,本申请实施例提供的基站、中心站及非线性信号处理方法不限于应用于ROF系统,还可以应用于基于ROF的模拟光载无线通信网架构、类似中心站和分布式基站单元组网的通信网架构、多个模拟头端通过光传输介质(例如光纤或光电混合缆)对接少量中心站的通信网架构(例如多个模拟头端对接一个中心站的网络架构)等网络架构中。此外,本申请实施例提供的基站、中心站及非线性信号处理方法也可以应用于其它各种无线通信系统中,以解决无线通信系统中非线性元器件引起的非线性失真问题。所述无线通信系统例如可以为长期演进(long term evolution,LTE)系统、2G、3G、4G、5G通信系统或下一代通信系统(如6G系统)等。还应理解,本申请实施例提供的基站、中心站及非线性信号处理方法也不仅限于能够解决二阶互调失真问题,还可以解决谐波失真(如HD2)、交调失真(如IMD3)等各种非线性失真问题。It should be understood that the base station, central station and nonlinear signal processing method provided in the embodiments of the present application are not limited to be applied to the ROF system, and can also be applied to the ROF-based analog optical wireless communication network architecture, similar central stations and distributed base station unit groups In network architectures such as the communication network architecture of the network, the communication network architecture in which multiple analog heads connect to a small number of central stations through optical transmission media (such as optical fiber or optical hybrid cable) (such as the network architecture in which multiple analog heads connect to a central station), etc. . In addition, the base station, the central station, and the nonlinear signal processing method provided in the embodiments of the present application can also be applied to various other wireless communication systems, so as to solve the problem of nonlinear distortion caused by nonlinear components in the wireless communication system. The wireless communication system may be, for example, a long term evolution (long term evolution, LTE) system, a 2G, 3G, 4G, 5G communication system, or a next generation communication system (such as a 6G system). It should also be understood that the base station, central station, and nonlinear signal processing method provided in the embodiments of the present application are not limited to solving the second-order intermodulation distortion problem, and can also solve harmonic distortion (such as HD2), intermodulation distortion (such as IMD3) and other nonlinear distortion problems.
图5为本申请实施例提供的一种ROF系统的架构示意图。如图5中所示,本申请实施例中,ROF系统采用数模混合架构。在ROF系统中,基站主要由光模块、数字链路、模拟链路等部分构成。这些部分构成了基站中的下行发射(transport,TX)链路及上行接收((receive,RX)链路,基站可以通过上行接收链路将来自用户设备的信号发送到中心站,也可以通过下行发射链路将来自中心站的信号发送到用户设备。FIG. 5 is a schematic structural diagram of an ROF system provided by an embodiment of the present application. As shown in FIG. 5 , in the embodiment of the present application, the ROF system adopts a digital-analog hybrid architecture. In the ROF system, the base station is mainly composed of optical modules, digital links, analog links and other parts. These parts constitute the downlink transmit (transport, TX) link and uplink receive (receive, RX) link in the base station. The base station can send the signal from the user equipment to the central station through the uplink receive link, or through the downlink The transmit link sends the signal from the central station to the user equipment.
其中,光模块主要用于将射频电信号转换为光信号后发送到中心站,或者接收来自中心站的光信号并将其转换为射频电信号。数字链路部分可以通过现场可编程门阵列(field programmable gate array,FPGA)或者专用集成电路(application specific integrated circuit,ASIC)或者数字信号处理(digital signal processor,DSP)电路等方式来实现。数字链路部分可以实现诸如数字滤波、信道选择、数字处理等功能。模拟链路部分至少包括放大器(如功率放大器(power amplifier,PA)、LNA等)等元器件或模块,模拟链路可以用于对基站接收到的信号进行初步处理,并将信号传输到数字链路进行进一步处理。这里需要说明的是,图5中是以数字链路部分实现为DSP、模拟链路部分包含PA或LNA为例进行示意的,但数字链路或模拟链路的结构或实现方式不仅限于图5中示意的方式。Among them, the optical module is mainly used to convert the radio frequency electrical signal into an optical signal and then send it to the central station, or receive the optical signal from the central station and convert it into a radio frequency electrical signal. The digital link part can be realized by way of field programmable gate array (field programmable gate array, FPGA) or application specific integrated circuit (application specific integrated circuit, ASIC) or digital signal processing (digital signal processor, DSP) circuit. The digital link part can realize functions such as digital filtering, channel selection, and digital processing. The analog link part includes at least components or modules such as amplifiers (such as power amplifiers (PA), LNA, etc.), and the analog link can be used for preliminary processing of the signal received by the base station and transmits the signal to the digital link. way for further processing. What needs to be explained here is that in Figure 5, the digital link part is implemented as a DSP, and the analog link part includes PA or LNA as an example, but the structure or implementation of the digital link or analog link is not limited to Figure 5 in the manner indicated.
中心站主要包括光模块、信号处理模块等。其中,光模块主要用于将射频电信号转换为光信号后发送到基站,或者接收来自基站的光信号并将其转换为射频电信号。信号处理模块主要用于实现基带(baseband,BB)信号、中频(intermediate frequency,IF)信号、射频(radio frequency)信号之间的转换处理。The central station mainly includes optical modules, signal processing modules, etc. Among them, the optical module is mainly used to convert the radio frequency electrical signal into an optical signal and then send it to the base station, or receive the optical signal from the base station and convert it into a radio frequency electrical signal. The signal processing module is mainly used to implement conversion processing among baseband (baseband, BB) signals, intermediate frequency (intermediate frequency, IF) signals, and radio frequency (radio frequency) signals.
基站与中心站之间可以通过光传输介质连接,其中,光传输介质可以为光纤、光电混合缆等。The base station and the central station may be connected through an optical transmission medium, wherein the optical transmission medium may be an optical fiber, a photoelectric hybrid cable, or the like.
上述ROF系统中,基站是数模混合设计的头端架构,相比常规纯模拟设计的头端架构,功能设计上具有更大的灵活性,同时性能上具有独特的优势,特别是针对系统非线性校正问题,下面结合具体实施例进行详细说明。In the above-mentioned ROF system, the base station is a head-end architecture with a digital-analog hybrid design. Compared with the conventional head-end architecture with a purely analog design, it has greater flexibility in function design and has unique advantages in performance, especially for non-standard systems. The problem of linear correction will be described in detail below in conjunction with specific embodiments.
实施例一Embodiment one
图6为本申请实施例提供的一种基站的示意图。如图6中所示,本实施例中,所述基站可以包括多个射频链路(例如图6中所示的射频链路1、射频链路2、射频链路3)、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2。FIG. 6 is a schematic diagram of a base station provided by an embodiment of the present application. As shown in FIG. 6, in this embodiment, the base station may include multiple radio frequency links (such as radio frequency link 1, radio frequency link 2, and radio frequency link 3 shown in FIG. 6), optical modules, and feature A computing module; wherein, the number of the plurality of radio frequency links is greater than or equal to two.
需要说明的是,为方便介绍,图6中只示例出所述基站包括3个射频链路的情况,实际基站中可能存在更多或更少数量个射频链路,在此不再赘述。It should be noted that, for the convenience of introduction, only the case where the base station includes 3 radio frequency links is illustrated in FIG. 6 , and there may be more or less radio frequency links in the actual base station, which will not be repeated here.
在该基站中,每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号。其中,任一路或多路信号可以为来自一个用户设备的信号,不同路的信号可以是来自不同用户设备的信号。In the base station, each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and transmit the one signal to the optical module after performing radio frequency processing on the one signal. Wherein, any one or more signals may be signals from one user equipment, and signals of different channels may be signals from different user equipments.
所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理得到包含处理后的所述多路信号的光信号,并将所述光信号发送到中心站,及对所述光信号进行光电转换处理得到电信号并将所述电信号发送到所述特征计算模块;其中,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述光模块中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠;所述光信号中包含所述非线性失真信号、所述多路信号。The optical module is configured to perform electro-optical conversion processing on the multi-channel signals from the plurality of radio frequency links to obtain an optical signal including the processed multi-channel signals, and send the optical signal to the central station, and Performing photoelectric conversion processing on the optical signal to obtain an electrical signal and sending the electrical signal to the feature calculation module; wherein, there are a first radio frequency link and at least one second radio frequency link among the plurality of radio frequency links , the optical module includes a nonlinear component, and the signal of the at least one second radio frequency link passes through the nonlinear component to generate a nonlinear distortion signal, and the frequency band of the nonlinear distortion signal is the same as that of the first The frequency bands corresponding to the radio frequency links overlap; the optical signal includes the nonlinear distortion signal and the multichannel signal.
可选的,所述基站中还包含合路模块(图6中未示出),所述合路模块用于接收来自所述多个射频链路的多路信号,并对所述多路信号进行合路处理,得到合路信号,并将所述合路信号发送到所述光模块。则所述光模块用于接收来自所述合路模块的所述合路信号,并对所述合路信号进行电光转换处理得到所述光信号。示例性的,所述合路模块可以为合路器。Optionally, the base station further includes a combiner module (not shown in FIG. 6 ), the combiner module is configured to receive multiple signals from the multiple radio frequency links, and combine the multiple signals Perform combination processing to obtain a combination signal, and send the combination signal to the optical module. The optical module is used to receive the combined signal from the combined module, and perform electro-optical conversion processing on the combined signal to obtain the optical signal. Exemplarily, the combining module may be a combiner.
每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块。Each second radio frequency link is further configured to perform radio frequency processing on a received signal of a corresponding frequency band, and then send the obtained signal to the feature calculation module.
所述特征计算模块,用于从来自所述光模块的所述电信号中提取目标信号,其中,所述目标信号为所述电信号中包含的所述第一射频链路对应的频段的信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号。The feature calculation module is configured to extract a target signal from the electrical signal from the optical module, wherein the target signal is a signal of a frequency band corresponding to the first radio frequency link included in the electrical signal ; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and send the nonlinear distortion prediction signal to the first radio frequency link, wherein the The nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
所述第一射频链路,还用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。The first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
在本申请一些实施例中,射频链路进行的射频处理可以包括滤波、功率或能量放大、变频、模数转换、传输速率调整、功率调整、数模转换等处理中的一项或多项。In some embodiments of the present application, the radio frequency processing performed by the radio frequency link may include one or more of filtering, power or energy amplification, frequency conversion, analog-to-digital conversion, transmission rate adjustment, power adjustment, and digital-to-analog conversion.
在本申请一些实施例中,所述第一射频链路对应的频段与所述非线性失真信号的频段有交叠,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率。其中,在一种可能的情况中,所述多个射频链路中存在一个第二射频链路,则所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;例如如图3中所示的场景3的情况。在另一种可能的情况中,所述多个射频链路中存在两个第二射频链路,则所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和,例如如图3中所示的场景1的情况;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差,例如如图3中所示的场景2的情况。In some embodiments of the present application, the frequency band corresponding to the first radio frequency link overlaps with the frequency band of the nonlinear distortion signal, the starting frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the The cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency. Wherein, in a possible situation, there is a second radio frequency link in the plurality of radio frequency links, then the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link , the second frequency is twice the cutoff frequency of the frequency band corresponding to the one second radio frequency link; for example, the scenario 3 shown in FIG. 3 . In another possible situation, if there are two second radio frequency links among the plurality of radio frequency links, the first frequency is the sum of the starting frequencies of the corresponding frequency bands of the two second radio frequency links , the second frequency is the sum of the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links, for example, the case of scenario 1 as shown in FIG. 3 ; or, the first frequency is the sum of the two second radio frequency links The difference between the start frequencies of the frequency bands corresponding to the two radio frequency links, and the second frequency is the difference between the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links, for example, the scenario 2 shown in FIG. 3 .
示例性的,所述多个射频链路中存在一个第二射频链路时,所述第一射频链路可以为图6中所示的射频链路3,所述一个第二射频链路可以为图6中所示的射频链路1或射频 链路2,所述射频链路1或所述射频链路2上的信号经过所述非线性元器件后生成非线性失真信号,且该非线性失真信号的频段与射频链路3上的信号的频段有交叠。所述多个射频链路中存在两个第二射频链路时,所述第一射频链路可以为图6中所示的射频链3,所述两个第二射频链路可以分别为图6中所示的射频链路1和射频链路2,所述射频链路1和所述射频链路2上的信号经过所述非线性元器件后生成非线性失真信号,且该非线性失真信号的频段与射频链路3上的信号的频段有交叠。Exemplarily, when there is a second radio frequency link among the plurality of radio frequency links, the first radio frequency link may be the radio frequency link 3 shown in FIG. 6 , and the second radio frequency link may be It is radio frequency link 1 or radio frequency link 2 shown in FIG. The frequency band of the linear distortion signal overlaps with the frequency band of the signal on the radio frequency link 3 . When there are two second radio frequency links in the plurality of radio frequency links, the first radio frequency link may be the radio frequency chain 3 shown in FIG. 6, and the two second radio frequency links may be respectively shown in FIG. The radio frequency link 1 and the radio frequency link 2 shown in 6, the signals on the radio frequency link 1 and the radio frequency link 2 generate a nonlinear distortion signal after passing through the nonlinear components, and the nonlinear distortion The frequency band of the signal overlaps with the frequency band of the signal on the radio frequency link 3 .
在本实施例中,所述光模块中可以包含电光转换模块、光电转换模块、第一端口、第二端口、第三端口。In this embodiment, the optical module may include an electro-optic conversion module, a photoelectric conversion module, a first port, a second port, and a third port.
在所述光模块中,所述第一端口,用于接收来自所述多个射频链路的所述多路信号,并传输到所述电光转换模块。In the optical module, the first port is used to receive the multiple signals from the multiple radio frequency links and transmit them to the electro-optic conversion module.
所述电光转换模块,与所述第一端口连接,用于对所述多路信号进行电光转换处理得到光信号,所述电光转换模块中包含所述非线性元器件,所述非线性元器件可以用于对信号进行电光转换处理。示例性的,所述非线性元器件为电光转换器,例如LD。The electro-optic conversion module is connected to the first port, and is used to perform electro-optical conversion processing on the multi-channel signal to obtain an optical signal, the electro-optic conversion module includes the nonlinear component, and the nonlinear component It can be used for electrical-optical conversion processing of signals. Exemplarily, the nonlinear component is an electro-optical converter, such as an LD.
可选的,在所述基站中包含所述合路模块时,所述第一端口与所述合路模块连接,则所述第一端口用于接收来自所述合路模块的所述合路信号,并传输到所述电光转换模块。则所述电光转换模块用于对所述合路信号进行电光转换处理,得到所述光信号。Optionally, when the base station includes the combining module, the first port is connected to the combining module, and the first port is used to receive the combining module from the combining module. signal and transmit it to the electro-optical conversion module. The electro-optical conversion module is used to perform electro-optical conversion processing on the combined signal to obtain the optical signal.
所述第二端口,与所述电光转换模块连接,用于将所述电光转换模块得到的所述光信号发送出去,例如通过光传输介质将所述光信号发送到中心站。The second port is connected to the electro-optical conversion module, and is used to send the optical signal obtained by the electro-optical conversion module, for example, to send the optical signal to a central station through an optical transmission medium.
所述光电转换模块,用于接收来自所述电光转换模块的所述光信号,并对所述光信号进行光电转换处理,得到所述电信号。示例性的,所述光电转换模块为光电转换器,例如PD。The photoelectric conversion module is configured to receive the optical signal from the electro-optical conversion module, and perform photoelectric conversion processing on the optical signal to obtain the electrical signal. Exemplarily, the photoelectric conversion module is a photoelectric converter, such as a PD.
在本申请一些实施例中,所述光电转换模块接收的来自所述电光转换模块的所述光信号,可以是从所述电光转换模块进行电光转换处理得到的光信号中采样得到的。In some embodiments of the present application, the optical signal received by the photoelectric conversion module from the electro-optic conversion module may be obtained by sampling an optical signal obtained by performing electro-optic conversion processing by the electro-optic conversion module.
所述第三端口,与所述光电转换模块连接,用于将所述光电转换模块得到的所述电信号发送到所述特征计算模块。The third port is connected to the photoelectric conversion module, and is used to send the electrical signal obtained by the photoelectric conversion module to the feature calculation module.
在本实施例中,所述特征计算模块包括滤波模块、迭代计算模块。In this embodiment, the feature calculation module includes a filter module and an iterative calculation module.
在所述特征计算模块中,所述滤波模块,用于接收所述光电转换模块通过所述第三端口发送的电信号,并对所述电信号进行滤波处理,得到所述目标信号。示例性的,所述滤波模块为滤波器。In the feature calculation module, the filtering module is configured to receive the electrical signal sent by the photoelectric conversion module through the third port, and filter the electrical signal to obtain the target signal. Exemplarily, the filtering module is a filter.
在本申请一些实施例中,所述滤波模块对所述电信号进行滤波处理时,可以以所述第一射频链路的信号频段作为参考进行滤波,来滤除所述电信号中与所述第一射频链路的信号频段不同的频段的信号。In some embodiments of the present application, when the filtering module performs filtering processing on the electrical signal, it may use the signal frequency band of the first radio frequency link as a reference to perform filtering, so as to filter out the electrical signal that is related to the electrical signal. A signal in a frequency band different from the signal frequency band of the first radio frequency link.
可选的,所述特征计算模块中还可以包含功率放大模块,所述功率放大模块连接在所述滤波器之后,用于对所述滤波器得到的目标信号进行功率或能量放大。示例性的,所述功率放大模块可以为LNA。Optionally, the feature calculation module may further include a power amplification module, which is connected after the filter and used to amplify the power or energy of the target signal obtained by the filter. Exemplarily, the power amplification module may be an LNA.
所述迭代计算模块,所述迭代计算模块可以用于:接收来自所述滤波器的所述目标信号,以及接收来自所述至少一个第二射频链路的至少一路信号,并根据所述目标信号计算目标参数,根据所述至少一个第二射频链路的至少一路信号计算目标预测信号,再根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。其中,所述目标参数用于表征所述非线性元器件的非线性失真特性,所述目标预测信号为所述非线性失 真信号的第二预测信号。The iterative calculation module, the iterative calculation module can be used to: receive the target signal from the filter, and receive at least one signal from the at least one second radio frequency link, and according to the target signal calculating a target parameter, calculating a target prediction signal according to at least one signal of the at least one second radio frequency link, and then correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal. Wherein, the target parameter is used to characterize the nonlinear distortion characteristic of the nonlinear component, and the target prediction signal is the second prediction signal of the nonlinear distortion signal.
具体的,所述迭代计算模块接收所述目标信号后,根据设定的第一计算模型及所述目标信号,计算所述目标参数,以及根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。其中,上述设定的第一计算模型、设定的第二计算模型可以通过预先进行模型训练得到。Specifically, after receiving the target signal, the iterative calculation module calculates the target parameter according to the set first calculation model and the target signal, and calculates the target parameter according to the set second calculation model and the at least one first calculation model. Calculate the target prediction signal for at least one signal of two radio frequency links, wherein the first calculation model is used to represent one of the multiple signals input to the nonlinear component, and the output of the nonlinear component The corresponding relationship between the nonlinear distortion signal with the same frequency band of the one signal and the nonlinear distortion characteristic parameter of the nonlinear component; the second calculation model is used to represent the relationship between at least one signal passing through the nonlinear component and Correspondence between the nonlinear distortion signals generated after the at least one signal passes through the nonlinear components. Wherein, the above set first calculation model and the set second calculation model can be obtained by performing model training in advance.
所述迭代计算模块计算得到所述目标参数和所述目标预测信号后,将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。其中,所述目标参数是根据实际通过非线性元器件的至少一路信号以及该至少一路信号经过该非线性元器件后实际产生的非线性失真信号得到的非线性失真系数,可以更为准确的反映非线性元器件的非线性失真特性。所述目标预测信号是仅根据所述至少一个第二射频链路的至少一路信号,对所述至少一路信号经过非线性元器件之后产生的非线性失真信号进行预估得到的,在预估得到一个非线性失真预测信号(即所述第二预测信号)的基础上进一步采用对应的目标参数对预估得到的非线性失真预测信号进行修正,能够得到更准确的非线性失真预测信号(即所述第一预测信号),从而大大提高根据最终得到的非线性失真预测信号对所述第一射频链路的信号进行预失真处理的准确度。After the iterative calculation module calculates the target parameter and the target prediction signal, the target parameter is multiplied by the target prediction signal to obtain the nonlinear distortion prediction signal. Wherein, the target parameter is a nonlinear distortion coefficient obtained according to at least one signal actually passing through the nonlinear component and the nonlinear distortion signal actually generated after the at least one signal passes through the nonlinear component, which can more accurately reflect Nonlinear distortion characteristics of nonlinear components. The target prediction signal is obtained only by predicting a nonlinear distortion signal generated after the at least one signal passes through a nonlinear component based on at least one signal of the at least one second radio frequency link. On the basis of a nonlinear distortion prediction signal (that is, the second prediction signal), the corresponding target parameters are further used to correct the estimated nonlinear distortion prediction signal, and a more accurate nonlinear distortion prediction signal (that is, the second prediction signal) can be obtained. The first prediction signal), so as to greatly improve the accuracy of pre-distortion processing on the signal of the first radio frequency link according to the finally obtained nonlinear distortion prediction signal.
在本申请一些实施例中,所述特征计算模块还包括反馈模块,所述反馈模块可以用于对所述基站中的射频链路接收的信号进行时延校正。所述反馈模块可以位于所述迭代计算模块与所述滤波器之间,所述反馈模块用于接收来自所述滤波器的所述目标信号和来自所述至少一个第二射频链路的至少一路信号,并对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号,并将得到的信号发送到迭代计算模块。In some embodiments of the present application, the feature calculation module further includes a feedback module, and the feedback module can be used to perform delay correction on signals received by the radio frequency link in the base station. The feedback module may be located between the iterative calculation module and the filter, and the feedback module is used to receive the target signal from the filter and at least one channel from the at least one second radio frequency link signal, and perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link to obtain the target signal and at least one signal of the at least one second radio frequency link with consistent delays signal, and send the obtained signal to the iterative calculation module.
具体的,参阅图7,所述反馈模块中可以包括锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块。Specifically, referring to FIG. 7 , the feedback module may include a lock module, a correlator, a threshold decision module, a delay calculation module, and a delay alignment module.
所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器。其中,所述锁数模块可以通过锁存器实现。The locking module is configured to respectively latch signals with a set time slot length from the at least one second radio frequency link, and send the latched signals to the correlator. Wherein, the number lock module can be realized by a latch.
作为一种可选的实施方式,所述锁数模块可以采用固定时隙锁数,例如所述锁数模块可按无线通信帧结构,以设定时长(如10ms)同步信号为基准,固定延迟采集并分别锁存来自所述至少一个第二射频链路的信号,其中,不同延迟对应不同时隙的信号。例如,在固定延迟为5ms时,所述锁数模块采集第10-20ms之间的共10ms时间长度的信号后,下一次采集时,则采集第15-25ms之间的共10ms时间长度的信号。As an optional implementation, the number lock module can use a fixed time slot lock number, for example, the number lock module can be based on a wireless communication frame structure, with a set duration (such as 10ms) synchronization signal as a reference, a fixed delay Collecting and respectively latching signals from the at least one second radio frequency link, wherein different delays correspond to signals of different time slots. For example, when the fixed delay is 5 ms, after the lock module collects signals with a total time length of 10 ms between the 10th and 20 ms, in the next collection, it collects signals with a total time length of 10 ms between the 15th and 25 ms .
作为另一种可选的实施方式,所述锁数模块可以按照所述门限判决模块的控制进行信号采集及锁存,下文中详细说明。As another optional implementation manner, the lock module may perform signal acquisition and latch according to the control of the threshold judgment module, which will be described in detail below.
所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性成分信号。The correlator is configured to perform correlation processing on the target signal and the signal from the lock module to obtain a correlation signal, and send the correlation signal to the threshold judgment module, wherein the correlation signal is Nonlinear component signal.
具体的,所述相关器对所述目标信号和来自所述锁数模块的信号进行相关处理时,首 先可以根据来自所述锁数模块的信号即所述至少一个第二射频链路的至少一路信号确定所述目标预测信号,再对所述目标信号和所述目标预测信号进行相关处理,得到所述相关信号。其中,所述相关器可以采用与所述迭代计算模块相同的方式确定所述目标预测信号。Specifically, when the correlator performs correlation processing on the target signal and the signal from the number-locking module, firstly, according to the signal from the number-locking module, that is, at least one channel of the at least one second radio frequency link signal to determine the target prediction signal, and then perform correlation processing on the target signal and the target prediction signal to obtain the correlation signal. Wherein, the correlator may determine the target prediction signal in the same manner as the iterative calculation module.
所述门限判决模块,用于接收来自所述相关器的所述相关信号,判断接收到的所述相关信号的相关值(或累加值或相关累加值)是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理。The threshold judgment module is configured to receive the correlation signal from the correlator, and judge whether the correlation value (or accumulation value or correlation accumulation value) of the received correlation signal is greater than or equal to a set value, and if so, Then send the related signal to the delay calculation module, otherwise, do not process the related signal.
在本申请一些实施例中,所述门限判决模块还可以用于对所述锁数模块进行锁存控制。具体的,所述门限判决模块在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块启动锁存或进行锁存更新,分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号。其中,所述设定时隙长度可根据实际需求灵活设置。所述门限判决模块在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块暂停锁存信号,即停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号,直至所述门限判决模块再次确定来自相关器的相关信号的相关值大于所述设定阈值时,所述门限判决模块再指示所述锁数模块继续锁存信号并更新锁存的信号。In some embodiments of the present application, the threshold decision module may also be used to perform latch control on the lock module. Specifically, when the threshold determination module determines that the correlation value of the correlation signal is greater than or equal to the set value, it instructs the lock module to start latching or perform latch update, and respectively latches signals from the at least one The second radio frequency link sets the signal of the time slot length, and replaces the previously latched signal with the currently latched signal. Wherein, the set time slot length can be flexibly set according to actual needs. When the threshold judgment module determines that the correlation value of the correlation signal is less than the set value, instruct the lock module to suspend the latch signal, that is, stop latching the settings from the at least one second radio frequency link time slot length until the threshold judgment module again determines that the correlation value of the correlation signal from the correlator is greater than the set threshold, then the threshold judgment module instructs the lock module to continue latching the signal and updating the lock stored signal.
所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块。The delay calculation module is configured to calculate the signal of the first radio frequency link and the at least one second radio frequency link according to the correlation signal when receiving the correlation signal from the threshold judgment module The time delay between the signals of the set time slot length, and send the time delay to the time delay alignment module.
所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号,从而分别保留所述目标信号和所述至少一个第二射频链路的信号中时延一致的信号。The delay alignment module is configured to, after receiving the delay from the delay calculation module, remove the setting between the target signal and the at least one second radio frequency link according to the delay. Signals with the time delay in the signals with a fixed slot length, and respectively removing the signals with the time delay with the target signal in the signals with the set time slot length of each second radio frequency link, thereby respectively retaining The target signal is a signal with the same time delay as the signal of the at least one second radio frequency link.
通过上述方式,所述迭代计算模块接收到的目标信号和所述至少一个第二射频链路的信号之间基本不存在时延,可以保证对应的非线性失真预测信号的准确计算,进而提高后续预失真处理的准确度。Through the above method, there is basically no time delay between the target signal received by the iterative calculation module and the signal of the at least one second radio frequency link, which can ensure the accurate calculation of the corresponding nonlinear distortion prediction signal, thereby improving the subsequent The accuracy of the predistortion process.
上述迭代计算模块计算得到非线性失真预测信号后,将所述非线性失真预测信号发送到所述第一射频链路,所述第一射频链路接收到所述非线性失真预测信号后,根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理。具体的,所述第一射频链路将所述第一射频链路对应频段的信号减去所述非线性失真预测信号后,得到对所述第一射频链路对应频段的信号进行预失真处理后的信号。所述第一射频链路对进行预失真处理后的信号进行射频处理后,发送到所述光模块,所述光模块可以将该信号发送到中心站。After the above iterative calculation module calculates the nonlinear distortion prediction signal, it sends the nonlinear distortion prediction signal to the first radio frequency link, and the first radio frequency link receives the nonlinear distortion prediction signal, according to The nonlinear distortion prediction signal performs pre-distortion processing on signals in a frequency band corresponding to the first radio frequency link. Specifically, after the first radio frequency link subtracts the nonlinear distortion prediction signal from the signal in the frequency band corresponding to the first radio frequency link, the predistortion processing is performed on the signal in the frequency band corresponding to the first radio frequency link. after the signal. The first radio frequency link performs radio frequency processing on the predistorted signal, and then sends it to the optical module, and the optical module can send the signal to the central station.
可选的,所述第一射频链路上包含预失真处理模块,所述预失真处理模块用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理。示例性的,所述预失真处理模块可以为加法器或乘法器或乘加组合模块,其中,所述乘加组合模块具备乘法器和加法器的功能。Optionally, the first radio frequency link includes a pre-distortion processing module, and the pre-distortion processing module is configured to perform pre-distortion processing on a signal in a frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal . Exemplarily, the pre-distortion processing module may be an adder, a multiplier, or a multiplication-add combination module, wherein the multiplication-add combination module has functions of a multiplier and an adder.
上述实施例中,基站可以基于实际经过非线性元器件的信号以及该信号经过非线性元器件后实际产生的非线性失真信号,计算非线性元器件的非线性失真特性参数,能够提高确定非线性元器件的非线性失真特性的准确度。基站确定非线性元器件的非线性失真参数 后,再结合该参数和传输链路上当前传输的信号,预估信号经过非线性元器件时产生的非线性失真预测信号,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传输链路上当前传输的信号进行预失真处理,从而实现对传输链路上信号经过非线性元器件时产生的非线性失真问题的校正,提高进行非线性失真校正的准确度,同时,该方法的应用范围广泛,能够对各种不同非线性元件引起的非线性失真信号进行更为的准确预测,也便于对各种非线性元器件引起的非线性失真问题进行校正,因此该方法的通用性和适应性较强。In the above embodiment, the base station can calculate the nonlinear distortion characteristic parameters of the nonlinear components based on the signal actually passing through the nonlinear component and the nonlinear distortion signal actually generated after the signal passes through the nonlinear component, which can improve the determination of nonlinear The accuracy of the nonlinear distortion characteristics of a component. After the base station determines the nonlinear distortion parameter of the nonlinear component, it combines the parameter with the signal currently transmitted on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear component, which can improve the determined nonlinear The accuracy of the distortion prediction signal can further pre-distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components The correction of the problem can improve the accuracy of nonlinear distortion correction. At the same time, the method has a wide range of applications, and can more accurately predict the nonlinear distortion signals caused by various nonlinear components, and is also convenient for various nonlinear distortion signals. The nonlinear distortion problem caused by linear components is corrected, so the method has strong versatility and adaptability.
下面结合具体应用场景,以所述多个射频链路中存在两个第二射频链路为例,结合具体实例对本申请上述实施例提供的基站进行说明。The base station provided in the foregoing embodiments of the present application will be described below in combination with specific application scenarios and by taking two second radio frequency links among the plurality of radio frequency links as an example.
图8为本申请实施例提供的一种ROF系统的示意图。示例性的,参照图8,本申请实施例提供的基站可以应用于ROF系统中,所述基站至少包含三个射频链路,分别为所述第一射频链路和所述两个第二射频链路。所述三个射频链路可以分别通过天线接收三路不同频段的信号,例如图8中所示,第一射频链路接收的第一路信号表示为f1、两个第二射频链路接收的第二路信号和第三路信号分别表示为f2和f3。Fig. 8 is a schematic diagram of an ROF system provided by an embodiment of the present application. Exemplarily, referring to FIG. 8 , the base station provided by the embodiment of the present application can be applied in a ROF system, and the base station includes at least three radio frequency links, which are respectively the first radio frequency link and the two second radio frequency links link. The three radio frequency links can respectively receive signals of three different frequency bands through the antenna. For example, as shown in FIG. The second signal and the third signal are denoted as f2 and f3 respectively.
在图6所示的基站应用于ROF系统中时,基站中还可以包括上述图5所示的ROF系统中的一些元器件或模块,以及其它用于进行信号处理的元器件或模块,下面举例说明。When the base station shown in Figure 6 is applied to the ROF system, the base station may also include some components or modules in the ROF system shown in Figure 5 above, as well as other components or modules for signal processing, the following example illustrate.
基站中每个射频链路包含数字链路和模拟链路,所述数字链路例如可以实现为图8中所示的DSP,所述模拟链路例如可以实现为图8中所示的LNA。LNA可以作为高频或中频前置放大器或放大电路,能够对信号的功率或能量进行放大,具有低噪声和高增益的优点。Each radio frequency link in the base station includes a digital link and an analog link. The digital link may be implemented as a DSP shown in FIG. 8 , and the analog link may be implemented as an LNA shown in FIG. 8 . LNA can be used as a high frequency or intermediate frequency preamplifier or amplifying circuit, which can amplify the power or energy of the signal, and has the advantages of low noise and high gain.
可选的,基站中每个射频链路还可以包括滤波器、加法器、数据处理模块等。其中,滤波器可以用于对信号进行滤波处理,保留或滤除特定频段(或频率)的信号。加法器可以用于将所述第一射频链路对应频段的信号减去所述非线性失真预测信号,实现对所述第一射频链路对应频段的信号的预失真处理。数据处理模块可以用于对射频链路上信号的传输速率、增益等特性进行调整。当然,射频链路中也可以包含其它元器件或模块,至于射频链路中具体包括哪些元器件或模块,可根据实际需求进行灵活调整,此处不再详述。Optionally, each radio frequency link in the base station may further include a filter, an adder, a data processing module, and the like. Among them, the filter can be used to perform filtering processing on the signal, and keep or filter out the signal of a specific frequency band (or frequency). The adder may be used to subtract the nonlinear distortion prediction signal from the signal in the frequency band corresponding to the first radio frequency link, so as to implement pre-distortion processing on the signal in the frequency band corresponding to the first radio frequency link. The data processing module can be used to adjust the transmission rate, gain and other characteristics of the signal on the radio frequency link. Of course, other components or modules may also be included in the radio frequency link. As for which components or modules are specifically included in the radio frequency link, it can be flexibly adjusted according to actual needs, and will not be described in detail here.
基站中的合路模块为合路器,所述合路器用于对所述三个射频链路的信号进行合路处理,得到合路信号,或者,所述合路器用于对所述基站中包含所述三个射频链路在内的多个射频链路的信号进行合路处理,得到合路信号。可选的,所述合路器的功能可以通过加法器实现,即所述合路器可以为加法器。The combiner module in the base station is a combiner, and the combiner is used to combine the signals of the three radio frequency links to obtain a combined signal, or the combiner is used to combine the signals in the base station Signals of multiple radio frequency links including the three radio frequency links are combined and processed to obtain a combined signal. Optionally, the function of the combiner may be implemented by an adder, that is, the combiner may be an adder.
基站中的光模块中可以包括电光转换元器件如LD,所述光模块可以将所述电光转换元器件转换后的信号发送到中心站。可选的,基站中光模块还可以包括光电转换元器件如PD,所述光电转换元器件用于将来自中心站的信号转换为电信号。The optical module in the base station may include an electro-optic conversion component such as an LD, and the optical module may send the signal converted by the electro-optic conversion component to the central station. Optionally, the optical module in the base station may further include a photoelectric conversion component such as a PD, and the photoelectric conversion component is used to convert a signal from the central station into an electrical signal.
基站中的特征计算模块中可以包括光电转换器、滤波模块、功率放大模块、模拟反馈模块、数字反馈模块、迭代计算模块等。其中,模拟反馈模块主要用于对信号进行模数转换,可以通过模数转换器实现;数字反馈模块即为上述的反馈模块,用于对信号进行时延校正处理。其它元器件或模块的功能可参照上述实施例中的描述,此处不再赘述。The feature calculation module in the base station may include a photoelectric converter, a filter module, a power amplification module, an analog feedback module, a digital feedback module, an iterative calculation module, and the like. Wherein, the analog feedback module is mainly used to perform analog-to-digital conversion on the signal, which can be realized by an analog-to-digital converter; the digital feedback module is the above-mentioned feedback module, which is used to perform delay correction processing on the signal. For the functions of other components or modules, reference may be made to the descriptions in the above embodiments, and details are not repeated here.
示例性的,如图8中所示,第一射频链路的信号f1和两个第二射频链路接收的信号f2和f3经过一系列射频处理后被发送到合路器,在所述合路器完成合路得到信号f1、信号 f2和信号f3合路的电信号。在该过程中,由于特征计算模块暂未采样到信号进行计算,因此,特征计算模块没有输出,信号f1经过加法器时未发生变化。信号f1、信号f2和信号f3合路的电信号被传输到光模块的电光转换器,电光转换器可以将电信号转换为光信号并通过光传输介质发送到中心站。同时,特征计算模块可以采样电光转换器转换得到的光信号,并通过光电转换器将采样的光信号再转换为电信号。其中,电光转换器为非线性元器件,由于电光转换器的非线性特征,在对信号f1、信号f2和信号f3合路的电信号进行电光转换的过程中,信号f2和信号f3会发生互调作用产生二阶互调的非线性失真信号,该非线性失真信号表示为imd2(信号imd2的频段与信号f1的频段有交叠),则光电转换器输出的信号中包含信号f1、信号f2、信号f3和信号imd2,则光电转换器对光信号进行光电转换后输出的信号中也包含信号f1、信号f2、信号f3和信号imd2。通过滤波器对该信号进行滤波处理后可以获得只包含与信号f1的频段相同的信号,即目标信号,该目标信号中包含信号f1和信号imd2中与信号f1频段相同的部分或全部信号(为便于描述,本申请实施例中仍称之为信号imd2)。该目标信号经过功率放大模块、模拟反馈模块进行相应处理后到达数字反馈模块。数字反馈模块对所述目标信号、信号f2、信号f3进行时延校正处理后,将得到的校正后的目标信号、信号f2及信号f3发送到迭代计算模块。迭代计算模块根据修正后的目标信号、信号f2、信号f3计算第一非线性失真预测信号,并将计算得到的第一非线性失真预测信号发送到第一射频链路上的预失真处理模块如加法器中。此后,第一射频链路上接收的信号f1经过加法器处理,被减去所述第一非线性失真预测信号(预测的imd2信号)后,通过相关元器件传输到光模块的电光转换器。电光转换器对信号进行电光转换处理的过程中,产生的imd2信号与先前减去的所述第一非线性失真信号互为补偿,使得电光转换器得到的光信号中基本去除了imd2信号,从而尽可能避免imd2信号对信号f1的干扰。Exemplarily, as shown in FIG. 8, the signal f1 of the first radio frequency link and the signals f2 and f3 received by the two second radio frequency links are sent to the combiner after a series of radio frequency processing, and the combined The circuit breaker completes the combination to obtain the electrical signal of the combination of the signal f1, the signal f2 and the signal f3. In this process, since the feature calculation module has not sampled the signal for calculation, the feature calculation module has no output, and the signal f1 does not change when passing through the adder. The combined electrical signal of signal f1, signal f2 and signal f3 is transmitted to the electro-optical converter of the optical module, and the electro-optical converter can convert the electrical signal into an optical signal and send it to the central station through the optical transmission medium. At the same time, the feature calculation module can sample the optical signal converted by the electro-optical converter, and convert the sampled optical signal into an electrical signal through the photoelectric converter. Among them, the electro-optic converter is a nonlinear component. Due to the nonlinear characteristics of the electro-optic converter, in the process of electro-optical conversion of the electrical signal combined with the signal f1, the signal f2 and the signal f3, the signal f2 and the signal f3 will interact with each other. The modulation effect produces a nonlinear distortion signal of second-order intermodulation, the nonlinear distortion signal is expressed as imd2 (the frequency band of the signal imd2 overlaps with the frequency band of the signal f1), and the output signal of the photoelectric converter includes the signal f1 and the signal f2 , signal f3 and signal imd2, the signal output by the photoelectric converter after photoelectric conversion of the optical signal also includes signal f1, signal f2, signal f3 and signal imd2. After the signal is filtered by a filter, the signal containing only the same frequency band as the signal f1 can be obtained, that is, the target signal, which includes part or all of the signal f1 and the signal imd2 in the same frequency band as the signal f1 (for For convenience of description, it is still referred to as the signal imd2) in the embodiment of the present application. The target signal reaches the digital feedback module after corresponding processing by the power amplification module and the analog feedback module. After the digital feedback module performs delay correction processing on the target signal, signal f2 and signal f3, it sends the obtained corrected target signal, signal f2 and signal f3 to the iterative calculation module. The iterative calculation module calculates the first nonlinear distortion prediction signal according to the corrected target signal, signal f2, and signal f3, and sends the calculated first nonlinear distortion prediction signal to the predistortion processing module on the first radio frequency link such as in the adder. Thereafter, the signal f1 received on the first radio frequency link is processed by an adder, and after being subtracted from the first nonlinear distortion prediction signal (predicted imd2 signal), it is transmitted to the electro-optical converter of the optical module through related components. During the electro-optical conversion process of the signal by the electro-optical converter, the generated imd2 signal and the previously subtracted first nonlinear distortion signal compensate each other, so that the imd2 signal is basically removed from the optical signal obtained by the electro-optical converter, thereby Avoid the interference of imd2 signal to signal f1 as much as possible.
需要说明的是,上述第一射频链路和两个第二射频链路对信号的接收是同步的,即三个射频链路是同时接收到对应的三路信号的。It should be noted that the reception of signals by the first radio frequency link and the two second radio frequency links is synchronous, that is, the three radio frequency links receive corresponding three-way signals at the same time.
下面参阅图9,对图8中所示的数字反馈模块的处理过程进行简单说明。如图9中所示,数字反馈模块一方面通过锁存模块分别采样锁存两个第二射频链路的信号,并将锁存的信号发送到相关器,其中,锁存的两个第二射频链路的信号分别表示为信号f2_latch和信号f3_latch,相关器对信号f2_latch和信号f3_latch经过所述电光转换器后产生的非线性失真信号进行预测计算,得到对应的非线性失真预测信号,并对该非线性失真信号和所述目标信号fb进行相关处理得到非线性成分的相关信号,门限判决模块确定该相关信号的相关值大于或等于设定阈值时,将该相关信号发送到时延计算模块。时延计算模块根据相关信号计算得到目标信号fb与信号f2、信号f3之间的时延,并发送到时延对齐模块。时延对齐模块可以根据所述时延,分别从目标信号fb、信号f2、信号f3中提取出时延一致的信号并发送到迭代计算模块。其中,时延对齐模块从目标信号中提取的信号为信号fb_align,从信号f2_latch中提取的信号为信号f2_latch_align,从信号f3_latch中提取的信号为信号f3_latch_align,信号fb_align、信号f2_latch_align和信号f3_latch_align之间不存在时延。Referring to FIG. 9, the processing procedure of the digital feedback module shown in FIG. 8 will be briefly described. As shown in Figure 9, on the one hand, the digital feedback module samples and latches the signals of the two second radio frequency links through the latch module, and sends the latched signals to the correlator, wherein the latched two second The signals of the radio frequency link are represented as the signal f2_latch and the signal f3_latch respectively, and the correlator predicts and calculates the nonlinear distortion signal generated after the signal f2_latch and the signal f3_latch pass through the electro-optical converter, and obtains the corresponding nonlinear distortion prediction signal, and The nonlinear distortion signal and the target signal fb are subjected to correlation processing to obtain a correlation signal of a nonlinear component, and when the threshold judgment module determines that the correlation value of the correlation signal is greater than or equal to a set threshold, the correlation signal is sent to the delay calculation module . The time delay calculation module calculates the time delays between the target signal fb and the signals f2 and f3 according to the relevant signals, and sends them to the time delay alignment module. The time delay alignment module can extract signals with consistent time delays from the target signal fb, signal f2, and signal f3 respectively according to the time delays, and send them to the iterative calculation module. Wherein, the signal extracted by the delay alignment module from the target signal is the signal fb_align, the signal extracted from the signal f2_latch is the signal f2_latch_align, the signal extracted from the signal f3_latch is the signal f3_latch_align, and there is no difference between the signal fb_align, the signal f2_latch_align and the signal f3_latch_align There is a delay.
需要说明的是,上述图8或图9中所示的系统架构仅是对本申请实施例适用系统架构的举例说明,本申请实施例适用的系统架构相比图8或图9所示的系统架构还可以增加其它实体,或减少部分实体,图8或图9中所示的终端结构中也可以增加其它结构或减少部分结构(或元器件)。上述图8或图9中所示的各种元器件也仅作为能够实现对应功能的 元器件的示例,各元器件也可以替换为能够实现对应功能的其它元器件。It should be noted that the above-mentioned system architecture shown in FIG. 8 or FIG. 9 is only an illustration of the system architecture applicable to the embodiment of the present application. Compared with the system architecture shown in FIG. 8 or FIG. 9, the system architecture applicable to the embodiment of the application Other entities can also be added, or some entities can be reduced, and other structures can also be added or some structures (or components) can be reduced in the terminal structure shown in FIG. 8 or FIG. 9 . The various components shown in Fig. 8 or Fig. 9 above are only examples of components that can realize corresponding functions, and each component can also be replaced with other components that can realize corresponding functions.
上述实施例中,基站是数模混合的结构,因此在基站的功能设计上,相比常规纯模拟设计的基站架构具有更大的灵活性,同时性能上具有独特优势。其中,在ROF系统的接收链路中,通过在光模块设计一个包含光电转换模块及特征计算模块的反馈通道,通过光模块内部反馈耦合的方式实现了非线性成分信号的耦合采样,并通过反馈通道环回给头端数字链路(例如上述的第一射频链路),从而在基站侧实现了对非线性失真信号的建模计算和对射频链路信号的预失真校正。因此,上述图8或图9所示的非线性失真校正方案也可以称为小回环校正方案。通过该方案,可以解决基站中非线性元器件产生的非线性失真,减小头端非线性对整个ROF系统的影响。In the above embodiments, the base station has a mixed digital-analog structure, so in terms of the function design of the base station, it has greater flexibility than the base station architecture with a conventional pure analog design, and at the same time has unique advantages in performance. Among them, in the receiving link of the ROF system, by designing a feedback channel including the photoelectric conversion module and the feature calculation module in the optical module, the coupling sampling of the nonlinear component signal is realized through the internal feedback coupling of the optical module, and through the feedback The channel is looped back to the head-end digital link (for example, the above-mentioned first radio frequency link), so that the modeling calculation of the nonlinear distortion signal and the pre-distortion correction of the radio frequency link signal are realized at the base station side. Therefore, the nonlinear distortion correction scheme shown in FIG. 8 or FIG. 9 may also be called a small loop correction scheme. Through this solution, the nonlinear distortion generated by the nonlinear components in the base station can be solved, and the impact of the head-end nonlinearity on the entire ROF system can be reduced.
需要说明的是,上述实施例中以本申请提供的非线性信号处理结构和方法应用在ROF系统中的接收链路中为例进行说明,实际应用中,上述实施例提供的非线性信号处理结构和方法也可以应用与ROF系统的发送链路中。此外,上述实施例提供的非线性信号处理结构和方法除了可以应用在基站侧,也可以应用在中心站侧,具体应用时可参照上述实施例中的相关介绍,此处不再赘述。It should be noted that, in the above embodiments, the application of the nonlinear signal processing structure and method provided by the present application in the receiving link of the ROF system is used as an example for illustration. In practical applications, the nonlinear signal processing structure provided by the above embodiments The sum method can also be applied in the transmission link of the ROF system. In addition, the nonlinear signal processing structure and method provided by the above embodiments can be applied not only at the base station side, but also at the central station side. For specific applications, refer to relevant introductions in the above embodiments, and details will not be repeated here.
本申请实施例提供的方案中,基站中的光模块相比目前已有的基站结构中的光模块,增加了一个耦合端口,即上述实施例中所述的第三端口,本申请实施例中通过该端口实现了反馈链路上的信号传输。示例性的,图10为本申请实施例提供的一种光模块结构的对比示意图。如图10中(a)示意图所示,当前基站结构中的单发单收(1T1R,即一根天线负责信号的发送和接收)模拟光模块是三端口的模块,包括1个用于在上行链路中接收电信号的输入电口、一个用于在下行链路中发送信号的输出电口和1个用于传输光信号的传输光口,分别为(a)示意图中所示的端口1、端口2和端口3。而本申请实施例的方案中,基站中的光模块是四端口模块,包括1个用于在上行链路中接收电信号的输入电口、一个用于在下行链路中发送信号的输出电口和1个用于传输光信号的传输光口,以及1个用于传输采样的电信号耦合电口,分别为(b)示意图中所示的端口1、端口2、端口3和端口4。其中,端口2、端口3和端口4分别为上述实施例中所述的第一端口、第二端口和第三端口。其具体应用方式可参照上述实施例中的介绍,这里不再赘述。In the solution provided by the embodiment of the present application, the optical module in the base station is compared with the optical module in the existing base station structure, and a coupling port is added, that is, the third port described in the above embodiment. In the embodiment of the present application The signal transmission on the feedback link is realized via this port. Exemplarily, FIG. 10 is a comparative schematic diagram of an optical module structure provided by an embodiment of the present application. As shown in the schematic diagram of (a) in Figure 10, the single-transmit-single-receive (1T1R, that is, one antenna is responsible for signal transmission and reception) analog optical module in the current base station structure is a three-port module, including one for uplink An input electrical port for receiving electrical signals in the link, an output electrical port for sending signals in the downlink, and a transmission optical port for transmitting optical signals, which are respectively port 1 shown in (a) schematic diagram , port 2, and port 3. In the solution of the embodiment of the present application, the optical module in the base station is a four-port module, including an input electrical port for receiving electrical signals in the uplink, and an output electrical port for sending signals in the downlink. port, a transmission optical port for transmitting optical signals, and an electrical signal coupling port for transmitting sampling, which are respectively port 1, port 2, port 3 and port 4 shown in (b) schematic diagram. Wherein, the port 2, the port 3 and the port 4 are respectively the first port, the second port and the third port described in the above embodiment. For its specific application manner, reference may be made to the introduction in the foregoing embodiments, which will not be repeated here.
需要说明的是,上述图8、图9或图10中所示的本申请实施例中光模块的结构为1T1R光模块的结构,实际上对于多发多收(多T多R,即多根天线分别负责信号的发送和接收)的光模块,同样可以增加多个本申请上述实施例提供的、包括特征计算模块在内的反馈通道来实现与上述相同的功能。其中,对于多T多R的光模块来说,可以每1T1R对应1个反馈通道(包括特征计算模块及前后链路),也可以多个1T1R共用一个反馈通道。It should be noted that the structure of the optical module in the embodiment of the present application shown in FIG. 8 , FIG. 9 or FIG. 10 is the structure of a 1T1R optical module. The optical modules responsible for the sending and receiving of signals respectively) can also add multiple feedback channels including the feature calculation module provided by the above-mentioned embodiments of the present application to realize the same functions as above. Among them, for a multi-T multi-R optical module, each 1T1R may correspond to one feedback channel (including the feature calculation module and front and back links), or multiple 1T1Rs may share one feedback channel.
图11为本申请实施例提供的一种基站结构的精简结构示意图。在本申请一些实施例中,如图11中所示,上述图8或图9中所示的小回环校正方案中,每个射频链路上的结构可划分为模拟链路和前向链路,其中,模拟链路主要用于实现信号传输、模数转换等模拟信号处理功能,前向链路用于实现与非线性失真信号预测、预失真校正相关的数字信号处理功能,例如两个第二射频链路中的前向链路部分可以用于将信号发送到特征计算模块等,第一射频链路中的前向链路部分可以用于进行预失真校正处理。光模块中主要包含电光转换模块和光电转换模块。可参照上述实施例中的介绍。反馈链路可结合已有系统链路构建反馈通道,并实现有用信号与非线性失真信号的时延对齐,主要包括上述的反馈模块。解算链路可利用反馈链路处理后的有用信号与非线性失真信号进行解算建模,计算出非线性失 真预测信号后反馈给第一射频链路的前向链路,从而使第一射频链路的前向链路根据所述非线性失真预测信号对第一射频链路上的信号进行预失真处理,以补偿链路中的非线性失真。FIG. 11 is a schematic diagram of a simplified structure of a base station structure provided by an embodiment of the present application. In some embodiments of the present application, as shown in FIG. 11 , in the above-mentioned small loop correction scheme shown in FIG. 8 or FIG. 9 , the structure on each radio frequency link can be divided into an analog link and a forward link , where the analog link is mainly used to implement analog signal processing functions such as signal transmission and analog-to-digital conversion, and the forward link is used to implement digital signal processing functions related to nonlinear distortion signal prediction and pre-distortion correction. For example, the two first The forward link part of the second radio frequency link may be used to send signals to the feature calculation module, etc., and the forward link part of the first radio frequency link may be used for predistortion correction processing. The optical module mainly includes an electro-optical conversion module and a photoelectric conversion module. Reference may be made to the introduction in the foregoing embodiments. The feedback link can be combined with the existing system link to build a feedback channel, and realize the time delay alignment of the useful signal and the nonlinear distortion signal, mainly including the above-mentioned feedback module. The calculation link can use the useful signal processed by the feedback link and the nonlinear distortion signal to perform calculation modeling, calculate the nonlinear distortion prediction signal, and feed it back to the forward link of the first radio frequency link, so that the first radio frequency The forward link of the radio frequency link performs predistortion processing on the signal on the first radio frequency link according to the nonlinear distortion prediction signal, so as to compensate the nonlinear distortion in the link.
需要说明的是,上述对基站结构的划分是示意性的,仅仅为一种逻辑功能划分,实际实现时可以有另外的划分方式,另外,在本申请各个实施例中的各功能模块可以是单独物理存在,也可以两个或两个以上模块集成在一个模块中。It should be noted that the above-mentioned division of the base station structure is schematic, and is only a logical function division. In actual implementation, there may be other division methods. In addition, each functional module in each embodiment of the present application may be a separate It exists physically, or two or more modules can be integrated in one module.
实施例二Embodiment two
图12为本申请实施例提供的一种基站和中心站的示意图,如图12中所示,本实施例中,所述基站可以包括多个射频链路(例如图12中所示的射频链路1、射频链路2)、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2。Fig. 12 is a schematic diagram of a base station and a central station provided by an embodiment of the present application. As shown in Fig. 12, in this embodiment, the base station may include multiple radio frequency links (such as the radio frequency chain shown in Fig. 12 1, radio frequency link 2), optical module, feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2.
需要说明的是,为方便介绍,图12中只示例出所述基站包括2个射频链路的情况,实际基站中可能存在更多或更少数量个射频链路,在此不再赘述。It should be noted that, for the convenience of introduction, only the case where the base station includes two radio frequency links is illustrated in FIG. 12 , and there may be more or less radio frequency links in the actual base station, which will not be repeated here.
在基站中,每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号。In the base station, each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and transmit the one signal to the optical module after performing radio frequency processing on the one signal.
所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理,得到包含处理后的所述多路信号的光信号,并将所述光信号发送到所述中心站,接收来自所述中心站的目标信号,对所述目标信号进行光电转换处理,并将处理后的所述目标信号发送到所述特征计算模块,其中,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述光模块中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠,所述光信号中还包含所述非线性失真信号;所述目标信号包含所述第一射频链路对应的频段的信号。The optical module is configured to perform electro-optic conversion processing on the multiple signals from the multiple radio frequency links, obtain an optical signal including the processed multiple signals, and send the optical signal to the center Station, receives the target signal from the central station, performs photoelectric conversion processing on the target signal, and sends the processed target signal to the feature calculation module, wherein there are The first radio frequency link and at least one second radio frequency link, the optical module includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate a nonlinear distorted signal, The frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link, and the optical signal also includes the nonlinear distortion signal; the target signal includes the frequency band corresponding to the first radio frequency link signal in the frequency band.
可选的,所述基站中还包含合路模块(图12中未示出),所述合路模块用于接收来自所述多个射频链路的多路信号,并对所述多路信号进行合路处理,得到合路信号,并将所述合路信号发送到所述光模块。则所述光模块用于接收来自所述合路模块的所述合路信号,并对所述合路信号进行电光转换处理得到所述光信号。示例性的,所述合路模块可以为合路器。Optionally, the base station further includes a combiner module (not shown in FIG. 12 ), the combiner module is used to receive multiple signals from the multiple radio frequency links, and combine the multiple signals Perform combination processing to obtain a combination signal, and send the combination signal to the optical module. The optical module is used to receive the combined signal from the combined module, and perform electro-optical conversion processing on the combined signal to obtain the optical signal. Exemplarily, the combining module may be a combiner.
每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块。Each second radio frequency link is further configured to perform radio frequency processing on a received signal of a corresponding frequency band, and then send the obtained signal to the feature calculation module.
所述特征计算模块,用于接收来自所述光模块的所述目标信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号。The feature calculation module is configured to receive the target signal from the optical module; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and calculate the The nonlinear distortion prediction signal is sent to the first radio frequency link, wherein the nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
所述第一射频链路,还用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。The first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
在本实施例中,所述光模块中包含电光转换模块,所述电光转换模块用于对所述多路信号进行电光转换处理得到光信号,所述电光转换模块中包含所述非线性元器件,所述非线性元器件可以用于对信号进行电光转换处理。示例性的,所述电光转换模块可以为LD。In this embodiment, the optical module includes an electro-optical conversion module, the electro-optical conversion module is used to perform electro-optical conversion processing on the multi-channel signal to obtain an optical signal, and the electro-optical conversion module includes the nonlinear component , the nonlinear component can be used to perform electro-optical conversion processing on signals. Exemplarily, the electro-optic conversion module may be an LD.
所述光模块将转换得到的光信号发送到中心站后,可以接收来自所述中心站的目标信 号,并对所述目标信号进行光电转换处理,将处理后的所述目标信号发送到所述特征计算模块。其中,作为一种可选的实施方式,所述光模块可以直接接收来自中心站的所述目标信号,并将所述目标信号发送到所述特征计算模块。作为另一种可选的实施方式,所述光模块可以接收来自所述中心站的下行信号,对所述下行信号进行光电转换处理,并将处理后的所述下行信号发送到所述特征计算模块,其中,所述下行信号中包含所述目标信号及其它待发送给所述基站的信号。则该方式中,所述特征计算模块可以通过接收来自所述光模块的所述下行信号,并对所述下行信号进行滤波处理,得到所述目标信号。After the optical module sends the converted optical signal to the central station, it can receive the target signal from the central station, perform photoelectric conversion processing on the target signal, and send the processed target signal to the Feature calculation module. Wherein, as an optional implementation manner, the optical module may directly receive the target signal from the central station, and send the target signal to the feature calculation module. As another optional implementation manner, the optical module may receive a downlink signal from the central station, perform photoelectric conversion processing on the downlink signal, and send the processed downlink signal to the feature calculation module, wherein the downlink signal includes the target signal and other signals to be sent to the base station. In this manner, the feature calculation module may obtain the target signal by receiving the downlink signal from the optical module and performing filtering processing on the downlink signal.
在本实施例中,所述特征计算模块包括滤波模块、迭代计算模块。In this embodiment, the feature calculation module includes a filter module and an iterative calculation module.
在所述特征计算模块中,所述滤波模块用于接收来自所述光模块的所述下行信号,并对所述下行信号进行滤波处理得到所述目标信号。示例性的,所述滤波模块为滤波器。关于所述迭代计算模块的功能可参照上述实施例一中关于迭代计算模块的说明,此处不再赘述。In the feature calculation module, the filtering module is configured to receive the downlink signal from the optical module, and filter the downlink signal to obtain the target signal. Exemplarily, the filtering module is a filter. For the functions of the iterative calculation module, reference may be made to the description of the iterative calculation module in Embodiment 1 above, which will not be repeated here.
可选的,所述特征计算模块中还可以包含分频模块,所述分频模块与所述光模块和所述滤波模块连接,所述分频模块可以用于接收来自所述光模块的下行信号,对所述下行信号进行分频处理,得到所述第一射频链路对应频段的信号,并将所述第一射频链路对应频段的信号发送到所述滤波器,则所述滤波器可以用于对所述第一射频链路对应频段的信号进行滤波处理,得到所述目标信号。Optionally, the feature calculation module may also include a frequency division module, the frequency division module is connected to the optical module and the filter module, and the frequency division module may be used to receive the downlink from the optical module signal, performing frequency division processing on the downlink signal to obtain a signal in the frequency band corresponding to the first radio frequency link, and sending the signal in the frequency band corresponding to the first radio frequency link to the filter, then the filter It can be used to perform filtering processing on the signal in the frequency band corresponding to the first radio frequency link to obtain the target signal.
在本申请一些实施例中,所述特征计算模块还包括反馈模块,关于所述反馈模块的结构、功能等可参照上述实施例一中关于反馈模块的说明,此处不再重述。In some embodiments of the present application, the feature calculation module further includes a feedback module. For the structure and function of the feedback module, please refer to the description of the feedback module in the first embodiment above, and will not be repeated here.
此外,需要说明的是,在本实施例中,如无特别说明,关于所述基站中各模块的结构、功能、特性等均可参照上述实施例一中的相关说明,本实施例中不再重述。In addition, it should be noted that in this embodiment, unless otherwise specified, reference can be made to the relevant descriptions in the first embodiment above for the structure, function, and characteristics of each module in the base station, and no further description will be given in this embodiment. restate.
本实施例中,中心站可以包括光模块、信号处理模块。In this embodiment, the central station may include an optical module and a signal processing module.
所述光模块,用于接收来自基站的光信号后,对所述光信号进行光电转换处理得到电信号,向所述信号处理模块发送所述电信号,其中,所述电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠。The optical module is configured to receive an optical signal from the base station, perform photoelectric conversion processing on the optical signal to obtain an electrical signal, and send the electrical signal to the signal processing module, wherein the electrical signal contains a nonlinear Distorted signals, multiple signals received by multiple radio frequency links of the base station through antennas, the number of the multiple radio frequency links is greater than or equal to 2, and the first radio frequency link and the first radio frequency link exist in the multiple radio frequency links At least one second radio frequency link, the base station includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate the nonlinear distortion signal, and the nonlinear distortion The frequency band of the signal overlaps with the frequency band corresponding to the first radio frequency link.
在本申请一些实施例中,中心站的光模块可以包含光电转换模块,所述光电转换模块用于接收来自基站的光信号,并将所述光信号转换为电信号。可选的,所述光电转换模块中包含非线性元器件。示例性的,所述光电转换模块可以为PD。In some embodiments of the present application, the optical module of the central station may include a photoelectric conversion module, and the photoelectric conversion module is configured to receive an optical signal from a base station and convert the optical signal into an electrical signal. Optionally, the photoelectric conversion module includes nonlinear components. Exemplarily, the photoelectric conversion module may be a PD.
示例性的,如图12中所示,所述基站的光模块通过电光转换模块得到光信号后,将所述光信号发送到所述中心站,所述中心站的光模块通过光电转换模块将所述光信号转换为电信号,并发送到信号处理模块。Exemplarily, as shown in FIG. 12, after the optical module of the base station obtains an optical signal through the electro-optical conversion module, the optical signal is sent to the central station, and the optical module of the central station transmits the optical signal through the photoelectric conversion module The optical signal is converted into an electrical signal and sent to a signal processing module.
所述信号处理模块,用于接收来自所述光模块的所述电信号,从所述电信号中提取所述第一射频链路对应的频段的目标信号,并将所述目标信号发送到所述光模块。The signal processing module is configured to receive the electrical signal from the optical module, extract the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal, and send the target signal to the Described optical module.
可选的,所述信号处理模块包含滤波模块,所述滤波模块用于接收来自所述光模块的所述电信号,对所述电信号进行滤波处理,得到所述目标信号,并发送到所述光模块。Optionally, the signal processing module includes a filtering module, and the filtering module is configured to receive the electrical signal from the optical module, perform filtering processing on the electrical signal, obtain the target signal, and send it to the Described optical module.
所述光模块,还用于对所述目标信号进行电光转换处理,并将处理后的所述目标信号发送到所述基站。具体的,所述光模块接收到来自所述信号处理模块的目标信号后,作为 一种可选的实施方式,所述光模块可以将所述目标信号直接单独发送到所述基站。作为另一种可选的实施方式,所述光模块可以对所述目标信号和其它待发送给所述基站的信号进行电光转换处理,得到包含所述目标信号和其它待发送给所述基站的信号的下行信号,并将所述下行信号发送到所述基站。The optical module is further configured to perform electro-optical conversion processing on the target signal, and send the processed target signal to the base station. Specifically, after the optical module receives the target signal from the signal processing module, as an optional implementation manner, the optical module may directly and separately send the target signal to the base station. As another optional implementation manner, the optical module may perform electrical-optical conversion processing on the target signal and other signals to be sent to the base station, to obtain the target signal and other signals to be sent to the base station the downlink signal of the signal, and send the downlink signal to the base station.
在本申请一些实施例中,中心站的光模块还可以包含电光转换模块,所述电光转换模块用于将电信号转换为光信号后,将该光信号发送到基站。可选的,所述电光转换模块中包含非线性元器件。示例性的,所述电光转换模块可以为LD。In some embodiments of the present application, the optical module of the central station may further include an electrical-to-optical conversion module, and the electrical-to-optical conversion module is configured to convert an electrical signal into an optical signal, and then send the optical signal to the base station. Optionally, the electro-optic conversion module includes nonlinear components. Exemplarily, the electro-optic conversion module may be an LD.
在本申请一些实施例中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率。其中,在一种可能的情况中,所述多个射频链路中存在一个第二射频链路,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍。在另一种可能的情况中,所述多个射频链路中存在两个第二射频链路,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。In some embodiments of the present application, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency. Wherein, in a possible situation, there is a second radio frequency link in the plurality of radio frequency links, and the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, The second frequency is twice the cutoff frequency of the frequency band corresponding to the one second radio frequency link. In another possible situation, there are two second radio frequency links among the plurality of radio frequency links, and the first frequency is the sum of starting frequencies of corresponding frequency bands of the two second radio frequency links, The second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, so The second frequency is the difference between the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links.
上述实施例中,基站将经过非线性元器件的信号以及该信号经过非线性元器件后产生的非线性失真信号发送到中心站后,中心站基于该信号得到目标信号,再将目标信号发送回基站,基站再根据该目标信号计算非线性元器件的非线性失真特性参数,一方面,使得基站能够基于实际信号和对应的实际非线性失真信号计算得到所述非线性失真特性参数,提高确定非线性元器件的非线性失真特性的准确度。基站确定非线性元器件的非线性失真参数后,再结合该参数和传输链路上当前传输的信号,预估信号经过非线性元器件时产生的非线性失真预测信号,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传输链路上当前传输的信号进行预失真处理,从而实现对传输链路上信号经过非线性元器件时产生的非线性失真问题的校正,提高进行非线性失真校正的准确度。另一方面,基站计算所述非线性失真特性参数所依据的信号经过了中心站的回传,因此该信号的传输路径包括了中心站中的一些传输链路,而基站中对非线性失真问题的校正方法可以校正非线性元器件所在的整个链路,因此该方案在对基站中非线性失真问题进行校正的同时,可以实现对中心站中一些非线性失真问题的校正,从而提高中心站与基站之间进行通信的准确度。In the above embodiment, after the base station sends the signal passing through the nonlinear components and the nonlinear distortion signal generated by the signal passing through the nonlinear components to the central station, the central station obtains the target signal based on the signal, and then sends the target signal back to base station, and the base station calculates the nonlinear distortion characteristic parameters of the nonlinear components according to the target signal. The accuracy of the nonlinear distortion characteristics of linear components. After the base station determines the nonlinear distortion parameter of the nonlinear component, it combines the parameter with the signal currently transmitted on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear component, which can improve the determined nonlinear The accuracy of the distortion prediction signal can further pre-distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components The correction of the problem improves the accuracy of nonlinear distortion correction. On the other hand, the signal on which the base station calculates the nonlinear distortion characteristic parameters is passed back by the central station, so the transmission path of the signal includes some transmission links in the central station, and the nonlinear distortion problem in the base station The correction method can correct the entire link where the nonlinear components are located. Therefore, while correcting the nonlinear distortion problems in the base station, this scheme can also correct some nonlinear distortion problems in the central station, thereby improving the communication between the central station and the central station. The accuracy of communication between base stations.
下面结合具体应用场景,以所述多个射频链路中存在一个第二射频链路为例,结合具体实例对本申请上述实施例提供的基站和中心站进行说明。The base station and the central station provided in the above embodiments of the present application will be described below in combination with specific application scenarios, taking one second radio frequency link among the plurality of radio frequency links as an example, in combination with specific examples.
图13为本申请实施例提供的一种ROF系统的示意图。示例性的,参照图13,本申请实施例提供的基站和中心站可以应用于ROF系统中,所述基站至少包含两个射频链路,分别为一个第一射频链路和一个第二射频链路。所述两个射频链路可以分别通过天线接收两路不同频段的信号,例如图13中所示,第一射频链路接收的第一路信号表示为f4、第二射频链路接收的第二路信号表示为f5。Fig. 13 is a schematic diagram of an ROF system provided by an embodiment of the present application. Exemplarily, referring to FIG. 13 , the base station and the central station provided by the embodiment of the present application can be applied in a ROF system, and the base station includes at least two radio frequency links, which are respectively a first radio frequency link and a second radio frequency link road. The two radio frequency links can respectively receive signals of two different frequency bands through antennas. For example, as shown in FIG. The road signal is denoted as f5.
在图13所示的基站应用于ROF系统中时,基站中还可以包括上述图5所示的ROF系统中的一些元器件或模块,以及其它用于进行信号处理的元器件或模块,具体可参照上述实施例一中的相关介绍,此处不再重述。When the base station shown in Figure 13 is applied to the ROF system, the base station may also include some components or modules in the ROF system shown in Figure 5 above, and other components or modules for signal processing, specifically Refer to the relevant introduction in the first embodiment above, which will not be repeated here.
示例性的,如图13中所示,第一射频链路接收的信号f4和第二射频链路接收的信号f5经过一系列射频处理后被发送到合路器,在所述合路器完成合路得到信号f4、信号f5合路的电信号,该电信号被传输到光模块的电光转换器,电光转换器可以将电信号转换为光信号并通过光传输介质发送到中心站。其中,电光转换器为非线性元器件,由于电光转换器的非线性特征,在对信号f4、信号f5合路的电信号进行电光转换的过程中,信号f5的频率成分会发生互调作用产生二阶互调的非线性失真信号,该非线性失真信号表示为imd2(信号imd2的频段与信号f4的频段有交叠),则基站的电光转换器发送到中心站的信号中包含信号f4、信号f5和信号imd2。中心站的光电转换模块接收到光信号后,将该光信号转换为电信号,并将电信号发送到信号处理模块。中心站的信号处理模块通过滤波器对该电信号进行滤波处理后可以获得只包含与信号f4的频段相同的信号,即目标信号,该目标信号中包含信号f4和信号imd2中与信号f4频段相同的部分或全部信号(为便于描述,本申请实施例中仍称之为信号imd2)。该目标信号与其它待发送给基站的各路信号经过中心站的电光转换器后,被一并发送到基站。基站的光电转换器接收到来自中心站的信号后,对该信号进行光电转换处理得到对应的电信号,并发送到特征计算模块。基站的特征计算模块通过分频模块对所述电信号进行分频处理,得到第一射频链路对应频段的信号,并通过滤波器对该信号进行滤波处理,得到目标信号,该目标信号经过功率放大模块、模拟反馈模块进行相应处理后到达数字反馈模块。数字反馈模块对所述目标信号、信号f5进行时延校正处理后,将得到的信号发送到迭代计算模块。迭代计算模块根据所述目标信号、信号f5计算第一非线性失真预测信号,并将计算得到的第一非线性失真预测信号发送到第一射频链路上的加法器中,通过加法器处理,将第一射频链路上的信号f4减去所述第一非线性失真预测信号(预测的imd2信号)后,通过相关元器件传输到光模块的电光转换器。电光转换器对信号进行电光转换处理的过程中,产生的imd2信号与先前减去的所述第一非线性失真信号互为补偿,使得电光转换器得到的光信号中基本去除了imd2信号,从而尽可能避免imd2信号对信号f4的干扰。Exemplarily, as shown in FIG. 13, the signal f4 received by the first radio frequency link and the signal f5 received by the second radio frequency link are sent to the combiner after a series of radio frequency processes, and the combiner completes Combined to obtain the electrical signal of signal f4 and signal f5 combined, the electrical signal is transmitted to the electro-optical converter of the optical module, the electro-optical converter can convert the electrical signal into an optical signal and send it to the central station through the optical transmission medium. Among them, the electro-optical converter is a nonlinear component. Due to the nonlinear characteristics of the electro-optic converter, in the process of electro-optical conversion of the electrical signal combined with the signal f4 and the signal f5, the frequency component of the signal f5 will undergo intermodulation. The nonlinear distortion signal of the second-order intermodulation, the nonlinear distortion signal is expressed as imd2 (the frequency band of the signal imd2 overlaps with the frequency band of the signal f4), and the signal sent by the electro-optical converter of the base station to the central station includes the signal f4, Signal f5 and signal imd2. After receiving the optical signal, the photoelectric conversion module of the central station converts the optical signal into an electrical signal, and sends the electrical signal to the signal processing module. The signal processing module of the central station can obtain the signal containing only the same frequency band as the signal f4 after filtering the electrical signal through a filter, that is, the target signal, which includes the signal f4 and the signal imd2 in the same frequency band as the signal f4 Part or all of the signals (for ease of description, it is still referred to as the signal imd2 in this embodiment of the application). The target signal and other signals to be sent to the base station are sent to the base station together after passing through the electro-optic converter of the central station. After the photoelectric converter of the base station receives the signal from the central station, it performs photoelectric conversion processing on the signal to obtain a corresponding electrical signal, and sends it to the feature calculation module. The characteristic calculation module of the base station performs frequency division processing on the electrical signal through the frequency division module to obtain a signal corresponding to the frequency band of the first radio frequency link, and performs filtering processing on the signal through a filter to obtain a target signal, and the target signal is passed through the power After corresponding processing by the amplification module and the analog feedback module, it reaches the digital feedback module. After the digital feedback module performs delay correction processing on the target signal and signal f5, the obtained signal is sent to the iterative calculation module. The iterative calculation module calculates the first nonlinear distortion prediction signal according to the target signal and signal f5, and sends the calculated first nonlinear distortion prediction signal to the adder on the first radio frequency link, and processes it through the adder, After subtracting the first nonlinear distortion prediction signal (predicted imd2 signal) from the signal f4 on the first radio frequency link, it is transmitted to the electro-optical converter of the optical module through related components. During the electro-optical conversion process of the signal by the electro-optical converter, the generated imd2 signal and the previously subtracted first nonlinear distortion signal compensate each other, so that the imd2 signal is basically removed from the optical signal obtained by the electro-optical converter, thereby Avoid the interference of imd2 signal to signal f4 as much as possible.
其中,需要说明的是,图13中所示的中心站中,光电转换器和电光转换器也是非线性元器件,若来自基站的信号在经过所述光电转换器或电光转换器时也产生了与信号f4的频段有交叠的非线性失真信号,则该非线性失真信号中与信号f4的频段有交叠的部分或全部信号也会携带在目标信号中一并回传到基站,则基站基于目标信号计算非线性失真预测信号时,能够考虑到信号在经过中心站过程中的非线性失真问题,并可以在预失真处理过程中,对中心站中的一些非线性失真进行校正,从而进一步提高对ROF系统的非线性失真的校正性能。Wherein, it should be noted that, in the central station shown in Fig. 13, the photoelectric converter and the electro-optical converter are also nonlinear components, if the signal from the base station passes through the photoelectric converter or the electro-optical converter also generates If there is a non-linear distortion signal overlapping the frequency band of the signal f4, part or all of the signals in the non-linear distortion signal overlapping the frequency band of the signal f4 will also be carried in the target signal and sent back to the base station, then the base station When calculating the nonlinear distortion prediction signal based on the target signal, the nonlinear distortion problem in the process of the signal passing through the central station can be considered, and some nonlinear distortion in the central station can be corrected during the pre-distortion process, so as to further Improve performance in correcting nonlinear distortions of ROF systems.
上述实施例中,信号从基站的空口天线接收口开始,在基站中经历了射频链路、光模块的电光转换器产生非线性,再经过光纤传输,到中心站光电转换器接收,再通过中心站的信号处理,经发射侧的电光转换器发出,再经过光纤环回给基站的光电转换器接收,经分频后通过反馈通道耦合给反馈链路进行非线性失真信号的预测等处理。能够利用基站和中心站原有的光模块实现非线性失真信号的大环回采样,送给基站的特征计算模块进行非线性失真信号的预测。从而在基站侧实现了对基站和中心站链路上的非线性失真信号的建模计算和对射频链路信号的预失真校正。因此,上述图13所示的非线性失真校正方案也可以称为大回环校正方案。通过该方案,可以解决基站及中心站中非线性元器件产生的非线性失真,减小基站及中心站中非线性对整个ROF系统的影响。In the above-mentioned embodiment, the signal starts from the receiving port of the air interface antenna of the base station, undergoes a radio frequency link in the base station, and the electro-optical converter of the optical module generates nonlinearity, and then transmits through the optical fiber, receives it at the photoelectric converter of the central station, and then passes through the central station. The signal processing of the station is sent by the electro-optical converter on the transmitting side, and then received by the photoelectric converter of the base station through the optical fiber loopback. After frequency division, it is coupled to the feedback link through the feedback channel for nonlinear distortion signal prediction and other processing. The original optical modules of the base station and the central station can be used to realize the large-loop sampling of the nonlinear distortion signal, which is sent to the feature calculation module of the base station to predict the nonlinear distortion signal. Therefore, the modeling calculation of the nonlinear distortion signal on the link between the base station and the central station and the pre-distortion correction of the radio frequency link signal are realized on the base station side. Therefore, the above nonlinear distortion correction scheme shown in FIG. 13 may also be referred to as a giant loop correction scheme. Through this solution, the nonlinear distortion generated by the nonlinear components in the base station and the central station can be solved, and the influence of the nonlinearity in the base station and the central station on the entire ROF system can be reduced.
实施例三Embodiment three
图14为本申请实施例提供的一种中心站的示意图,如图14中所示,本实施例中,所述中心站可以包括光模块、信号处理模块、特征计算模块。FIG. 14 is a schematic diagram of a central station provided by an embodiment of the present application. As shown in FIG. 14 , in this embodiment, the central station may include an optical module, a signal processing module, and a feature calculation module.
所述光模块,用于接收来自至少一个基站的光信号,对所述至少一个基站中每个基站的光信号进行光电转换处理,得到每个基站的电信号,分别将每个基站的电信号发送到所述信号处理模块和所述特征计算模块。其中,任一个基站的电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠。The optical module is configured to receive an optical signal from at least one base station, perform photoelectric conversion processing on the optical signal of each base station in the at least one base station, obtain an electrical signal of each base station, and convert the electrical signal of each base station to sent to the signal processing module and the feature calculation module. Wherein, the electrical signal of any base station includes nonlinear distortion signals, multiple signals received by multiple radio frequency links of the base station through antennas, the number of the multiple radio frequency links is greater than or equal to 2, and the multiple There are a first radio frequency link and at least one second radio frequency link in the radio frequency links, the base station contains nonlinear components, and the signal of the at least one second radio frequency link is generated after passing through the nonlinear components For the nonlinear distorted signal, a frequency band of the nonlinear distorted signal overlaps with a frequency band corresponding to the first radio frequency link.
其中,所述光模块通过不同的链路,分别将每个基站的电信号分别发送到所述信号处理模块。所述光模块通过不同的链路,分别将每个基站的电信号分别发送到所述特征计算模块。Wherein, the optical module sends the electrical signal of each base station to the signal processing module respectively through different links. The optical module sends the electrical signal of each base station to the feature calculation module through different links.
所述特征计算模块,用于分别接收来自所述光模块的每个基站的电信号;分别对每个基站的电信号进行特征计算处理,得到每个基站对应的非线性失真预测信号,并分别将每个基站对应的非线性失真预测信号发送到所述信号处理模块;其中,对任一个基站的电信号进行的特征计算处理包含以下步骤:从所述电信号中提取所述第一射频链路对应的频段的目标信号,以及,从所述电信号中分别提取来自所述至少一个第二射频链路的至少一路信号;根据所述目标信号和所述至少一个第二射频链路的至少一路信号计算所述非线性失真预测信号,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号。The feature calculation module is used to respectively receive the electrical signal from each base station of the optical module; respectively perform feature calculation processing on the electrical signal of each base station to obtain a nonlinear distortion prediction signal corresponding to each base station, and respectively The nonlinear distortion prediction signal corresponding to each base station is sent to the signal processing module; wherein, the feature calculation processing on the electrical signal of any base station includes the following steps: extracting the first radio frequency chain from the electrical signal target signal in a corresponding frequency band, and at least one signal from the at least one second radio frequency link is respectively extracted from the electrical signal; according to the target signal and at least one signal of the at least one second radio frequency link One channel of signals calculates the nonlinear distortion prediction signal, wherein the nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal.
所述信号处理模块,用于分别接收来自所述光模块的每个基站的电信号;对所述至少一个基站的电信号进行射频处理得到目标合路信号;其中,所述目标合路信号包含所述第一射频链路对应的频段的信号;所述射频处理可以包括合路处理及分频处理;分别接收来自所述特征计算模块的每个基站对应的非线性失真预测信号;依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理。The signal processing module is configured to respectively receive electrical signals from each base station of the optical module; perform radio frequency processing on the electrical signals of the at least one base station to obtain a target combining signal; wherein, the target combining signal includes The signal of the frequency band corresponding to the first radio frequency link; the radio frequency processing may include combination processing and frequency division processing; respectively receive the nonlinear distortion prediction signal corresponding to each base station from the feature calculation module; The nonlinear distortion prediction signals corresponding to the base stations perform distortion correction processing on the target combined signal.
在本申请一些实施例中,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中,在一种可能的情况中,所述多个射频链路中存在一个第二射频链路,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍。在另一种可能的情况中,所述多个射频链路中存在两个第二射频链路,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。In some embodiments of the present application, the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein, in a possible situation , there is a second radio frequency link in the plurality of radio frequency links, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the The second radio frequency link corresponds to twice the cutoff frequency of the frequency band. In another possible situation, there are two second radio frequency links among the plurality of radio frequency links, and the first frequency is the sum of starting frequencies of corresponding frequency bands of the two second radio frequency links, The second frequency is the sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, so The second frequency is the difference between the cut-off frequencies of the corresponding frequency bands of the two second radio frequency links.
在本实施例中,所述光模块中包含光电转换模块,所述光电转换模块用于分别对来自所述至少一个基站的光信号进行光电转换处理得到电信号。可选的,所述光电转换模块中包含非线性元器件,所述非线性元器件可以用于对信号进行光电转换处理。示例性的,所述光电转换模块可以为PD。In this embodiment, the optical module includes a photoelectric conversion module, and the photoelectric conversion module is configured to respectively perform photoelectric conversion processing on the optical signals from the at least one base station to obtain electrical signals. Optionally, the photoelectric conversion module includes nonlinear components, and the nonlinear components can be used to perform photoelectric conversion processing on signals. Exemplarily, the photoelectric conversion module may be a PD.
本实施例中,关于所述特征计算模块的结构、功能等可参照上述实施例一中关于特征计算模块的说明,此处不再赘述。In this embodiment, for the structure and function of the feature calculation module, reference may be made to the description of the feature calculation module in the first embodiment above, and details are not repeated here.
在本申请一些实施例中,所述信号处理模块包括射频处理模块、数字处理与补偿模块。 所述射频处理模块用于对所述光模块接收到的每个基站对应的信号进行射频处理,例如可以包括:对所述至少一个基站的电信号进行合路处理,得到合路信号,以及对所述合路信号进行分频处理,得到每个射频链路对应的频段的信号。其中,每个射频链路对应频段的信号中包含所述至少一个基站对应的该频段的信号,以及与该频段有交叠的非线性失真信号。例如如图14中所示的第一射频链路对应频段的信号,以及第二射频链路对应频段的信号。其中,所述第一射频链路对应频段的信号即为所述目标合路信号。所述数字处理与补偿模块用于依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理。具体的,所述数字处理与补偿模块将所述目标合路信号依次减去每个基站对应的非线性失真预测信号后,得到去除非线性失真信号的目标合路信号。In some embodiments of the present application, the signal processing module includes a radio frequency processing module, a digital processing and compensation module. The radio frequency processing module is configured to perform radio frequency processing on the signal corresponding to each base station received by the optical module, for example, it may include: performing combination processing on the electrical signals of the at least one base station to obtain a combined signal, and The combined signal is subjected to frequency division processing to obtain a signal of a frequency band corresponding to each radio frequency link. Wherein, the signal of the frequency band corresponding to each radio frequency link includes the signal of the frequency band corresponding to the at least one base station and the non-linear distortion signal overlapping with the frequency band. For example, as shown in FIG. 14 , a signal of a frequency band corresponding to the first radio frequency link, and a signal of a frequency band corresponding to the second radio frequency link. Wherein, the signal in the frequency band corresponding to the first radio frequency link is the target combining signal. The digital processing and compensation module is used to sequentially perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station. Specifically, the digital processing and compensation module sequentially subtracts the nonlinear distortion prediction signal corresponding to each base station from the target combined signal to obtain the target combined signal from which the nonlinear distortion signal has been removed.
示例性的,在所述至少一个基站中包含第一基站与第二基站、且每个基站通过两个射频链路接收两路信号时,第一基站发送到中心站的信号包含第一基站的第一射频链路上的信号、第一基站的第二射频链路的信号、所述第二射频链路的信号经过非线性元器件后产生的非线性失真信号。第二基站发送到中心站的信号包含第二基站的第一射频链路上的信号、第一基站的第二射频链路的信号、所述第二射频链路的信号经过非线性元器件后产生的非线性失真信号。则所述射频处理模块对所述至少一个基站的电信号进行合路处理得到的合路信号中至少包含上述六个信号。所述射频处理模块对所述合路信号进行分频处理后得到所述目标合路信号(包括第一基站的第一射频链路的信号、来自第一基站的非线性失真信号,以及第二基站的第一射频链路的信号、来自第二基站的非线性失真信号),然后可以依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理。具体的,所述信号处理模块可以先根据所述第一基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理,得到第一目标合路信号,再根据所述第二基站对应的非线性失真预测信号对所述第一目标合路信号进行失真校正处理,得到第二目标合路信号。其中,所述信号处理模块通过将所述目标合路信号减去所述第一基站对应的非线性失真预测信号,得到所述第一目标合路信号,通过将所述第一目标合路信号减去所述第二基站对应的非线性失真预测信号,得到所述第二目标合路信号。Exemplarily, when the at least one base station includes the first base station and the second base station, and each base station receives two signals through two radio frequency links, the signal sent by the first base station to the central station includes the signal of the first base station A signal on the first radio frequency link, a signal of the second radio frequency link of the first base station, and a nonlinear distorted signal generated after the signal of the second radio frequency link passes through a nonlinear component. The signal sent by the second base station to the central station includes the signal on the first radio frequency link of the second base station, the signal of the second radio frequency link of the first base station, and the signal of the second radio frequency link after passing through the nonlinear components The resulting non-linear distortion signal. Then, the combined signal obtained by combining the electrical signals of the at least one base station by the radio frequency processing module includes at least the above six signals. The radio frequency processing module performs frequency division processing on the combined signal to obtain the target combined signal (including the signal of the first radio frequency link of the first base station, the nonlinear distortion signal from the first base station, and the second The signal of the first radio frequency link of the base station, the nonlinear distortion signal from the second base station), and then perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to each base station. Specifically, the signal processing module may first perform distortion correction processing on the target combined signal according to the nonlinear distortion prediction signal corresponding to the first base station to obtain the first target combined signal, and then according to the second base station The corresponding nonlinear distortion prediction signal performs distortion correction processing on the first target combined signal to obtain a second target combined signal. Wherein, the signal processing module obtains the first target combined signal by subtracting the target combined signal from the nonlinear distortion prediction signal corresponding to the first base station, and obtains the first target combined signal by Subtracting the nonlinear distortion prediction signal corresponding to the second base station to obtain the second target combined signal.
在本申请一些实施例中,所述射频处理模块对所述光模块接收到的每个基站对应的信号进行射频处理时,也可以是对所述至少一个基站的电信号进行合路处理,得到合路信号。则该合路信号作为目标合路信号被发送到数字处理与补偿模块。所述数字处理与补偿模块用于将该目标合路信号依次减去每个基站对应的非线性失真预测信号,得到去除非线性失真信号之后的、所述至少一个基站的合路的信号。中心站可以在后续对所述至少一个基站的合路的信号进行处理的过程中,对该信号进行分频处理,得到每个射频链路对应的频段的信号。In some embodiments of the present application, when the radio frequency processing module performs radio frequency processing on the signals corresponding to each base station received by the optical module, it may also perform combined processing on the electrical signals of the at least one base station to obtain combined signal. Then the combined signal is sent to the digital processing and compensation module as the target combined signal. The digital processing and compensation module is used to sequentially subtract the target combined signal from the nonlinear distortion prediction signal corresponding to each base station to obtain the combined signal of the at least one base station after the nonlinear distortion signal is removed. During subsequent processing of the combined signal of the at least one base station, the central station may perform frequency division processing on the signal to obtain a signal in a frequency band corresponding to each radio frequency link.
在本申请一些实施例中,所述信号处理模块也可以仅包含数字处理与补偿模块,则所述数字处理与补偿模块可以分别根据每个基站对应的非线性失真预测信号,对光模块接收到的每个基站的信号进行失真校正处理,从而实现对来自不同基站的信号的独立处理。In some embodiments of the present application, the signal processing module may also only include a digital processing and compensation module, and then the digital processing and compensation module may separately receive the optical module according to the nonlinear distortion prediction signal corresponding to each base station. Distortion correction processing is performed on the signals of each base station, thereby realizing independent processing of signals from different base stations.
在本申请一些实施例中,所述特征计算模块除包含上述实施例一或实施例二所述的具体结构之外,还可以包含信号控制模块。所述信号控制模块用于对来自光模块的所述至少一个基站的电信号进行选择控制,使得所述特征计算模块在同一时间仅接收来自一个基站的电信号。示例性的,所述信号控制模块可以为单刀多掷开关,其中,单刀多掷开关的不动端与特征计算模块中的滤波模块连接,单刀多掷开关的动端分别与传输所述至少一个基 站的电信号的链路连接。通过所述单刀多掷开关可以选择将某一个链路传输的某一个基站的电信号传输到特征计算模块,便于针对该基站进行非线性失真预测信号的计算。In some embodiments of the present application, the feature calculation module may further include a signal control module in addition to the specific structure described in the first or second embodiment above. The signal control module is used to selectively control the electrical signal from the at least one base station of the optical module, so that the feature calculation module only receives the electrical signal from one base station at a time. Exemplarily, the signal control module may be a single-pole multi-throw switch, wherein the fixed end of the single-pole multi-throw switch is connected to the filter module in the characteristic calculation module, and the movable end of the single-pole multi-throw switch is respectively connected to the transmission of the at least one The link connection of the electrical signal of the base station. The electrical signal of a certain base station transmitted by a certain link can be selected to be transmitted to the characteristic calculation module through the single-pole multi-throw switch, so as to facilitate the calculation of the nonlinear distortion prediction signal for the base station.
在本申请一些实施例中,中心站中特征计算模块可以有多个,即中心站针对连接的每个基站设置一个对应的特征计算模块,则中心站的光电转换模块得到来自至少一个基站的电信号后,中心站在每一路信号对应的传输链路上分别耦合信号到对应的特征计算模块,通过特征计算模块对对应基站的非线性失真预测信号进行计算。每个基站对应的特征计算模块确定基站对应的非线性失真预测信号后,将确定的非线性失真预测信号分别发送到信号处理模块。In some embodiments of the present application, there may be multiple feature calculation modules in the central station, that is, the central station sets a corresponding feature calculation module for each connected base station, and then the photoelectric conversion module of the central station obtains electrical signals from at least one base station. After receiving the signal, the central station couples the signal to the corresponding feature calculation module on the transmission link corresponding to each signal, and calculates the nonlinear distortion prediction signal of the corresponding base station through the feature calculation module. After the feature calculation module corresponding to each base station determines the nonlinear distortion prediction signal corresponding to the base station, it sends the determined nonlinear distortion prediction signal to the signal processing module respectively.
作为一种可选的实施方式,信号处理模块可以根据每个基站对应的非线性失真预测信号分别对每个基站的电信号进行失真校正处理,这样可以对每一个单独的信号成分做非线性建模及失真校正处理,从而保证性能可达最佳。As an optional implementation, the signal processing module can respectively perform distortion correction processing on the electrical signal of each base station according to the nonlinear distortion prediction signal corresponding to each base station, so that each individual signal component can be nonlinearly constructed. Mode and distortion correction processing, so as to ensure the best performance.
作为另一种可选的实施方式,信号处理模块可以在对所述至少一个基站的电信号进行合路处理及分频处理后,根据每个基站对应的非线性失真预测信号依次对分频后得到的电信号进行失真校正处理,这样对汇聚合路后的信号做分离处理,可以实现多路信号分离的等价效果,进而可以针对每个成分信号进行非线性建模和失真校正处理,可以避免设置额外的物理通道。As another optional implementation manner, after the signal processing module performs combination processing and frequency division processing on the electrical signal of the at least one base station, it sequentially performs frequency division The obtained electrical signal is subjected to distortion correction processing, so that the signals after aggregation and channel separation can be separated to achieve the equivalent effect of multi-channel signal separation, and then nonlinear modeling and distortion correction processing can be performed for each component signal, which can Avoid setting up additional physical channels.
需要说明的是,在本实施例中,如无特别说明,一些模块的结构、功能、特性等可参照上述实施例一或实施二中的相关介绍,本实施例中不再赘述,例如,中心站中特征计算模块的结构中,除所述信号控制模块之外的结构可参照上述实施例一中关于特征计算模块的相关介绍。It should be noted that in this embodiment, unless otherwise specified, the structures, functions, and characteristics of some modules can refer to the relevant introductions in the above-mentioned Embodiment 1 or Embodiment 2, and will not be described in detail in this embodiment. For example, the center For the structure of the feature calculation module in the station, for the structure other than the signal control module, refer to the related introduction about the feature calculation module in the first embodiment above.
上述实施例中,中心站可以基于实际经过非线性元器件(基站或中心站中)的信号以及该信号经过非线性元器件后实际产生的非线性失真信号,计算非线性元器件的非线性失真特性参数,能够提高确定非线性元器件的非线性失真特性的准确度。中心站确定非线性元器件的非线性失真参数后,再结合该参数和传输链路上当前传输的信号,预估信号经过非线性元器件时产生的非线性失真预测信号,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对传输链路上当前传输的信号进行失真处理,从而实现对传输链路上信号经过非线性元器件时产生的非线性失真问题的校正,提高进行非线性失真校正的准确度。同时,中心站可以对来自多个基站的信号进行非线性失真的校正处理,提高了非线性失真校正的性能和效率。In the above embodiment, the central station can calculate the nonlinear distortion of the nonlinear component based on the signal actually passing through the nonlinear component (in the base station or the central station) and the nonlinear distortion signal actually generated after the signal passes through the nonlinear component The characteristic parameter can improve the accuracy of determining the nonlinear distortion characteristic of the nonlinear component. After the central station determines the nonlinear distortion parameters of the nonlinear components, it combines the parameters with the current transmission signal on the transmission link to estimate the nonlinear distortion prediction signal generated when the signal passes through the nonlinear components, which can improve the determined nonlinear distortion parameters. The accuracy of the linear distortion prediction signal can further distort the signal currently transmitted on the transmission link according to the determined nonlinear distortion prediction signal, so as to realize the nonlinear distortion generated when the signal on the transmission link passes through nonlinear components The correction of the problem improves the accuracy of nonlinear distortion correction. At the same time, the central station can perform nonlinear distortion correction processing on signals from multiple base stations, which improves the performance and efficiency of nonlinear distortion correction.
下面结合具体应用场景,以每个基站中存在一个第一射频链路和一个第二射频链路为例,结合具体实例对本申请上述实施例提供的基站进行说明。The base station provided by the above-mentioned embodiments of the present application will be described below in combination with specific application scenarios, taking a first radio frequency link and a second radio frequency link in each base station as an example, and specific examples.
图15为本申请实施例提供的一种ROF系统的示意图。示例性的,参照图15,本申请实施例提供的中心站可以应用于ROF系统中,所述中心站包括光模块、特征计算模块和信号处理模块,具体可参照上述实施例中的相关介绍。所述ROF系统中还包含n个基站,其中n为正整数。在所述n个基站中,每个基站包含两个射频链路,分别为第一射频链路和第二射频链路。所述两个射频链路可以分别通过天线接收两路不同频段的信号,例如图15中所示,第N个基站的第一射频链路接收的第一路信号表示为f1_N、第二射频链路接收的第二路信号表示为f2_N,其中N小于或等于n,且为正整数,所述n个基站中,各基站的第一射频链路对应的频段相同,各基站的第二射频链路对应的频段相同,各基站的第二 射频链路的信号经过非线性元器件后产生与第一射频链路对应的频段有交叠的非线性失真信号。Fig. 15 is a schematic diagram of an ROF system provided by an embodiment of the present application. Exemplarily, referring to FIG. 15 , the central station provided by the embodiment of the present application can be applied to an ROF system, and the central station includes an optical module, a feature calculation module, and a signal processing module. For details, refer to relevant introductions in the foregoing embodiments. The ROF system further includes n base stations, where n is a positive integer. Among the n base stations, each base station includes two radio frequency links, namely a first radio frequency link and a second radio frequency link. The two radio frequency links can respectively receive signals of two different frequency bands through the antenna. For example, as shown in FIG. The second signal received by the channel is expressed as f2_N, where N is less than or equal to n and is a positive integer. Among the n base stations, the frequency bands corresponding to the first radio frequency links of each base station are the same, and the second radio frequency links of each base station The frequency bands corresponding to the channels are the same, and the signals of the second radio frequency links of each base station pass through nonlinear components to generate nonlinear distortion signals overlapping with the frequency bands corresponding to the first radio frequency links.
示例性的,如图15中所示,第N个基站的第一射频链路接收的信号f1_N和第二射频链路接收的信号f2_N经过一系列射频处理后被发送到合路器,在所述合路器完成合路得到信号f1_N、信号f2_N合路的电信号,该电信号被传输到光模块的电光转换器,电光转换器可以将电信号转换为光信号并通过光传输介质发送到中心站。其中,电光转换器为非线性元器件,由于电光转换器的非线性特征,在对信号f1_N、信号f2_N合路的电信号进行电光转换的过程中,信号f2_N的频率成分会发生互调作用产生二阶互调的非线性失真信号,该非线性失真信号表示为imd2_N(信号imd2_N的频段与信号f1_N的频段有交叠),则基站的电光转换器实际发送到中心站的信号中包含信号f1_N、信号f2_N和信号imd2_N,表示为f1_N+f2_N+imd2_N。中心站的光电转换模块接收到光信号后,将该光信号转换为电信号,并将电信号发送到信号处理模块。中心站的信号处理模块通过射频处理模块对所述至少一个基站的电信号进行合路处理及分频处理得到不同射频链路对应频段的信号。分频后得到的信号中至少包含第一射频链路对应频段的信号,以及第二射频链路对应频段的信号。其中,第一射频链路对应频段的信号中至少包含信号f1_1~f1_n、分别与信号f1_1~f1_n的频段有交叠的非线性失真信号中的部分或全部信号(图15中表示为F1+imd2,其中,F1+imd2=f1_1+imd2_1+f1_2+imd2_2+…+f1_n+imd2_n),第二射频链路对应频段的信号中至少包含信号f2_1~f2_n(图15中表示为F2,其中,F2=f2_1+f2_2+…+f2_n)。特征计算模块分别根据每个基站的电信号(f1_N+f2_N+imd2_N)计算每个基站对应的非线性失真预测信号,并发送到信号处理模块。信号处理模块将所述第一射频链路对应频段的信号依次减去每个基站对应的非线性失真预测信号,实现对所述第一射频链路对应频段的信号的非线性失真校正。Exemplarily, as shown in FIG. 15, the signal f1_N received by the first radio frequency link of the Nth base station and the signal f2_N received by the second radio frequency link are sent to the combiner after a series of radio frequency processing, and then The combiner completes the combination to obtain the combined electrical signal of signal f1_N and signal f2_N, and the electrical signal is transmitted to the electro-optical converter of the optical module, which can convert the electrical signal into an optical signal and send it to central station. Among them, the electro-optical converter is a nonlinear component. Due to the nonlinear characteristics of the electro-optic converter, in the process of electro-optical conversion of the electrical signal combined with the signal f1_N and the signal f2_N, the frequency component of the signal f2_N will undergo intermodulation. The nonlinear distortion signal of the second-order intermodulation, the nonlinear distortion signal is expressed as imd2_N (the frequency band of the signal imd2_N overlaps with the frequency band of the signal f1_N), then the signal actually sent by the electro-optical converter of the base station to the central station contains the signal f1_N , signal f2_N and signal imd2_N, expressed as f1_N+f2_N+imd2_N. After receiving the optical signal, the photoelectric conversion module of the central station converts the optical signal into an electrical signal, and sends the electrical signal to the signal processing module. The signal processing module of the central station performs combination processing and frequency division processing on the electrical signals of the at least one base station through the radio frequency processing module to obtain signals corresponding to frequency bands of different radio frequency links. The signal obtained after frequency division at least includes a signal of a frequency band corresponding to the first radio frequency link and a signal of a frequency band corresponding to the second radio frequency link. Wherein, the signals of the frequency band corresponding to the first radio frequency link at least include some or all of the signals f1_1~f1_n and the non-linear distortion signals overlapping with the frequency bands of the signals f1_1~f1_n respectively (indicated as F1+imd2 in FIG. 15 , wherein, F1+imd2=f1_1+imd2_1+f1_2+imd2_2+...+f1_n+imd2_n), the signal of the frequency band corresponding to the second radio frequency link at least includes signals f2_1~f2_n (represented as F2 in Figure 15, where F2=f2_1 +f2_2+…+f2_n). The feature calculation module calculates the nonlinear distortion prediction signal corresponding to each base station according to the electrical signal (f1_N+f2_N+imd2_N) of each base station, and sends it to the signal processing module. The signal processing module sequentially subtracts the nonlinear distortion prediction signal corresponding to each base station from the signal in the frequency band corresponding to the first radio frequency link to implement nonlinear distortion correction for the signal in the frequency band corresponding to the first radio frequency link.
上述实施例一和实施例二的方案中,都是一对一的非线性失真校正,即一个非线性失真校正结构对应一个基站模块或通信链路。而在蜂窝移动通信系统中,通常一个中心站会连接多个基站(例如一个中心站连接八个基站等),这多个基站共用一个中心站的资源,因此,多个基站的信号最后会汇聚到一个中心站。因此,上述实施例三中,通过将校正链路设置在中心站,实现了中心站一驱多校正,即中共站不仅能校正基站中非线性器件造成的非线性失真,还能校正中心站中非线性器件引起的非线性失真。In the above-mentioned solutions of Embodiment 1 and Embodiment 2, both are one-to-one nonlinear distortion correction, that is, one nonlinear distortion correction structure corresponds to one base station module or communication link. In a cellular mobile communication system, usually a central station is connected to multiple base stations (for example, a central station is connected to eight base stations, etc.), and these multiple base stations share the resources of a central station, so the signals of multiple base stations will eventually converge. to a central station. Therefore, in the third embodiment above, by setting the correction link at the central station, one driver and multiple corrections at the central station are realized, that is, the central station can not only correct the nonlinear distortion caused by the nonlinear device in the base station, but also correct the Nonlinear distortion caused by nonlinear devices.
上述各实施例中,提供了基于数模混合的ROF新架构,有利于采用灵活的数字链路,更准确的解决ROF网络中模拟器件的非线性失真问题,解决了光器件等带来的非线性成分对ROF系统频率规划的约束,实现了ROF高性能低成本设计,能够提升5G及未来多模大带宽高速传输性能,使能站点低成本部署。In the above-mentioned embodiments, a new ROF architecture based on digital-analog hybrid is provided, which is conducive to adopting flexible digital links, more accurately solving the nonlinear distortion problem of analog devices in the ROF network, and solving the non-linear distortion caused by optical devices and the like. The constraint of the linear component on the frequency planning of the ROF system realizes the high-performance and low-cost design of ROF, which can improve the performance of 5G and future multi-mode large-bandwidth high-speed transmission and enable low-cost deployment of sites.
可以理解的是,上述各实施例中主要以解决基站的光模块中的非线性元器件引起的非线性失真问题为例,对本申请提供的方案进行介绍,但本申请方案的应用场景不限于此。对于基站或中心站中任意非线性元件引起的非线性失真问题,本申请提供的方案均可进行有效解决,此外,本申请提供的方案中是按照非线性失真成分校正进行重点描述的,实际上本申请提供的方案也可以应用于线性失真成分校正。上述各场景下,方案的具体实施方式可参照上述各实施例的介绍,这里不再一一说明。It can be understood that, in the above-mentioned embodiments, the solution to the nonlinear distortion problem caused by the nonlinear components in the optical module of the base station is used as an example to introduce the solution provided by the application, but the application scenario of the solution in the application is not limited to this . For the nonlinear distortion problem caused by any nonlinear element in the base station or central station, the scheme provided by this application can effectively solve it. In addition, the scheme provided by this application is mainly described according to the correction of nonlinear distortion components. In fact, The scheme provided in this application can also be applied to linear distortion component correction. For the specific implementation manners of the solution in each of the above scenarios, reference may be made to the introduction of the above embodiments, and no further description is given here.
基于以上实施例及相同构思,本申请实施例还提供一种非线性信号处理方法,该方法 可以应用于基站或中心站。如图16所示,本申请实施例提供的非线性信号处理方法应用于基站时,该方法包括:Based on the above embodiments and the same idea, this embodiment of the present application also provides a nonlinear signal processing method, which can be applied to a base station or a central station. As shown in Figure 16, when the nonlinear signal processing method provided in the embodiment of the present application is applied to a base station, the method includes:
S1601:基站根据目标信号计算目标参数,其中,所述目标信号包含:经过非线性元器件的第一信号、至少一个第二信号经过非线性元器件后生成的非线性失真信号,所述非线性失真信号的频段与所述第一信号的频段有交叠,所述目标参数用于表征所述非线性元器件的非线性失真特性。S1601: The base station calculates target parameters according to the target signal, wherein the target signal includes: a first signal passing through a nonlinear component, and a nonlinear distortion signal generated after at least one second signal passes through a nonlinear component, and the nonlinear The frequency band of the distorted signal overlaps with the frequency band of the first signal, and the target parameter is used to characterize the nonlinear distortion characteristic of the nonlinear component.
其中,所述第一信号的频段为第一频段,所述至少一个第二信号中,各信号的频段可以相同或不同。Wherein, the frequency band of the first signal is the first frequency band, and the frequency bands of the signals in the at least one second signal may be the same or different.
示例性的,所述第一信号可以为图3所示的场景一中的信号S F3,所述至少一个第二信号可以包含图3所示的场景二中的信号S F1和信号S F2;或者,所述第一信号可以为图3所示的场景二中的信号S F3,所述至少一个第二信号可以包含图3所示的场景二中的信号S F1和信号S F2;或者,所述第一信号可以为图3所示的场景三中的信号S F3,所述至少一个第二信号可以包含图3所示的场景三中的信号S F1Exemplarily, the first signal may be the signal S F3 in the scene one shown in FIG. 3 , and the at least one second signal may include the signal S F1 and the signal S F2 in the scene two shown in FIG. 3 ; Alternatively, the first signal may be the signal S F3 in the second scene shown in FIG. 3 , and the at least one second signal may include the signal S F1 and the signal S F2 in the second scene shown in FIG. 3 ; or, The first signal may be the signal S F3 in the third scene shown in FIG. 3 , and the at least one second signal may include the signal S F1 in the third scene shown in FIG. 3 .
在本申请一些实施例中,基站可以根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系。In some embodiments of the present application, the base station may calculate the target parameters according to the set first calculation model and the target signal, wherein the first calculation model is used to represent the multi-channel signals input to the nonlinear components The corresponding relationship between one channel of signal, the nonlinear distortion signal output by the nonlinear component with the same frequency band as the one of the signal, and the nonlinear distortion characteristic parameters of the nonlinear component.
S1602:基站根据所述至少一个第二信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的预测信号。S1602: The base station calculates a target prediction signal according to the at least one second signal, where the target prediction signal is a prediction signal of the nonlinear distortion signal.
其中,基站可以根据设定的第二计算模型及所述至少一个第二信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。Wherein, the base station may calculate the target prediction signal according to the set second calculation model and the at least one second signal, wherein the second calculation model is used to represent the relationship between the at least one signal passing through the nonlinear component and the The corresponding relationship between the nonlinear distortion signals generated after the at least one signal passes through the nonlinear components.
S1603:基站根据所述目标参数对所述目标预测信号进行修正,得到非线性失真预测信号。S1603: The base station corrects the target prediction signal according to the target parameter to obtain a nonlinear distortion prediction signal.
其中,所述非线性失真预测信号为修正后的、所述非线性失真信号的预测信号。Wherein, the nonlinear distortion prediction signal is a modified prediction signal of the nonlinear distortion signal.
基站在根据所述目标参数对所述目标预测信号进行修正时,可以将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。When correcting the target prediction signal according to the target parameter, the base station may multiply the target parameter by the target prediction signal to obtain the nonlinear distortion prediction signal.
上述实施例中,基站可以基于非线性元器件引起的非线性失真信号,对后续信号经过非线性元器件时产生的非线性失真信号进行预测计算,能够提高确定的非线性失真预测信号的准确度,进一步可以根据确定的非线性失真预测信号对有用信号进行预失真处理,从而实现对非线性元器件引起的非线性失真问题的校正,提高进行非线性失真校正的准确度。In the above embodiment, the base station can predict and calculate the nonlinear distortion signal generated when the subsequent signal passes through the nonlinear component based on the nonlinear distortion signal caused by the nonlinear component, which can improve the accuracy of the determined nonlinear distortion prediction signal Further, the useful signal can be pre-distorted according to the determined nonlinear distortion prediction signal, so as to realize the correction of the nonlinear distortion problem caused by the nonlinear components and improve the accuracy of nonlinear distortion correction.
本申请实施例提供的非线性信号处理方法应用于中心站时,可参照该方法应用于基站时的实施方式,此处不再赘述。When the nonlinear signal processing method provided in the embodiment of the present application is applied to the central station, reference may be made to the implementation manner when the method is applied to the base station, which will not be repeated here.
基于以上实施例及相同构思,本申请实施例还提供一种装置,所述装置包括存储器和处理器,所述存储器用于存储计算机程序,所述处理器用于执行所述存储器中存储的计算机程序,实现上述图16中所示的非线性信号处理方法。Based on the above embodiments and the same idea, an embodiment of the present application also provides a device, the device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory , realizing the nonlinear signal processing method shown in FIG. 16 above.
基于以上实施例及相同构思,本申请实施例还提供一种芯片,所述芯片可以包括上述实施例一中的基站所包含的元器件或模块;或者所述芯片可以包括上述实施例二中的基站所包含的元器件或模块;或者所述芯片可以包括上述实施例二中的中心站所包含的元器件 或模块;或者所述芯片可以包括上述实施例三中的中心站所包含的元器件或模块。Based on the above embodiments and the same idea, this embodiment of the present application also provides a chip, the chip may include the components or modules included in the base station in the first embodiment above; or the chip may include the components or modules in the second embodiment above The components or modules included in the base station; or the chip may include the components or modules included in the central station in the second embodiment above; or the chip may include the components included in the central station in the third embodiment above or modules.
基于以上实施例及相同构思,本申请实施例还提供一种通信系统,所述通信系统至少包括:上述实施例一中所提供的基站,或者上述实施例二中所提供的基站和中心站,或者上述实施例三中所提供的中心站。Based on the above embodiments and the same idea, the embodiments of the present application also provide a communication system, the communication system at least includes: the base station provided in the first embodiment above, or the base station and the central station provided in the second embodiment above, Or the central station provided in the third embodiment above.
显然,本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的范围。这样,倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内,则本申请也意图包含这些改动和变型在内。Apparently, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. In this way, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims (30)

  1. 一种基站,其特征在于,包括:多个射频链路、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2;A base station, characterized by comprising: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2;
    每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号;Each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and after performing radio frequency processing on the one signal, send the one signal to the optical module;
    所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理,得到包含处理后的所述多路信号的光信号;其中,所述光模块中包含非线性元器件,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠,所述光信号中还包含所述非线性失真信号;将所述光信号发送到中心站,及对所述光信号进行光电转换处理得到电信号并将所述电信号发送到所述特征计算模块;The optical module is configured to perform electro-optical conversion processing on the multi-channel signals from the multiple radio frequency links to obtain an optical signal including the processed multi-channel signals; wherein the optical module includes a nonlinear element A device, wherein there are a first radio frequency link and at least one second radio frequency link among the plurality of radio frequency links, and a signal of the at least one second radio frequency link generates a nonlinear distorted signal after passing through the nonlinear component, The frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link, and the optical signal also includes the nonlinear distortion signal; the optical signal is sent to the central station, and the performing photoelectric conversion processing on the optical signal to obtain an electrical signal and sending the electrical signal to the feature calculation module;
    每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块;Each second radio frequency link is also used to send the obtained signal to the feature calculation module after performing radio frequency processing on the received signal of the corresponding frequency band;
    所述特征计算模块,用于从来自所述光模块的所述电信号中提取目标信号;其中,所述目标信号包含所述电信号中包含的所述第一射频链路对应的频段的信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;The feature calculation module is configured to extract a target signal from the electrical signal from the optical module; wherein the target signal includes a signal of a frequency band corresponding to the first radio frequency link included in the electrical signal ; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and send the nonlinear distortion prediction signal to the first radio frequency link, wherein the The nonlinear distortion prediction signal is the first prediction signal of the nonlinear distortion signal;
    所述第一射频链路,还用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。The first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
  2. 根据权利要求1所述的基站,其特征在于,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:The base station according to claim 1, wherein the starting frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein:
    当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者When there is a second radio frequency link in the plurality of radio frequency links, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the Twice the cut-off frequency of the corresponding frequency band of a second radio frequency link; or
    当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。When there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the sum of the starting frequencies of the corresponding frequency bands of the two second radio frequency links, and the second frequency is the The sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, and the second frequency is the The difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  3. 根据权利要求1或2所述的基站,其特征在于,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:The base station according to claim 1 or 2, wherein the feature calculation module includes an iterative calculation module, and the iterative calculation module is used for:
    根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;calculating a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear distortion characteristics of the nonlinear component;
    根据所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;calculating a target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is a second prediction signal of the nonlinear distortion signal;
    根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。Correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal.
  4. 根据权利要求3所述的基站,其特征在于,所述迭代计算模块,在根据所述目标信号计算目标参数时,具体用于:The base station according to claim 3, wherein the iterative calculation module, when calculating the target parameter according to the target signal, is specifically used for:
    根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;Calculate the target parameters according to the set first calculation model and the target signal, wherein the first calculation model is used to represent one signal among the multiple signals input to the nonlinear component, the nonlinear element The corresponding relationship between the nonlinear distortion signal output by the device and the same frequency band as the one signal and the nonlinear distortion characteristic parameters of the nonlinear component;
    所述迭代计算模块根据所述至少一个第二射频链路的至少一路信号计算目标预测信号时,具体用于:When the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for:
    根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。Calculate the target prediction signal according to the set second calculation model and at least one signal of the at least one second radio frequency link, wherein the second calculation model is used to represent at least one signal passing through the nonlinear component Correspondence between the at least one signal and the nonlinear distortion signal generated after the at least one signal passes through the nonlinear component.
  5. 根据权利要求3或4所述的基站,其特征在于,所述迭代计算模块,在根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号时,具体用于:The base station according to claim 3 or 4, wherein the iterative calculation module, when correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal, is specifically used for:
    将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。The target parameter is multiplied by the target prediction signal to obtain the nonlinear distortion prediction signal.
  6. 根据权利要求1~5任一所述的基站,其特征在于,所述光模块包含:电光转换模块、光电转换模块、第一端口、第二端口、第三端口;The base station according to any one of claims 1-5, wherein the optical module comprises: an electro-optical conversion module, a photoelectric conversion module, a first port, a second port, and a third port;
    所述电光转换模块,用于对所述多路信号进行电光转换处理,所述电光转换模块包含所述非线性元器件;The electro-optical conversion module is used to perform electro-optical conversion processing on the multi-channel signal, and the electro-optic conversion module includes the nonlinear components;
    所述光电转换模块,用于对所述光信号进行光电转换处理;The photoelectric conversion module is used to perform photoelectric conversion processing on the optical signal;
    所述第一端口,用于接收所述多路信号;The first port is used to receive the multi-channel signal;
    所述第二端口,用于将所述光信号发送到所述中心站;the second port for sending the optical signal to the central station;
    所述第三端口,用于将所述电信号发送到所述特征计算模块。The third port is configured to send the electrical signal to the feature calculation module.
  7. 根据权利要求1~6任一所述的基站,其特征在于,所述特征计算模块还包括滤波模块;The base station according to any one of claims 1-6, wherein the feature calculation module further includes a filtering module;
    所述滤波模块,用于对所述电信号进行滤波处理,得到所述目标信号。The filtering module is configured to filter the electrical signal to obtain the target signal.
  8. 根据权利要求1~7任一所述的基站,其特征在于,所述特征计算模块还包括反馈模块,所述反馈模块用于:The base station according to any one of claims 1-7, wherein the feature calculation module further includes a feedback module, and the feedback module is used for:
    对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。Perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link to obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  9. 根据权利要求8所述的基站,其特征在于,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;The base station according to claim 8, wherein the feedback module comprises: a lock module, a correlator, a threshold judgment module, a delay calculation module, and a delay alignment module;
    所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器;The locking module is configured to respectively latch signals with a set time slot length from the at least one second radio frequency link, and send the latched signals to the correlator;
    所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;The correlator is configured to perform correlation processing on the target signal and the signal from the lock module to obtain a correlation signal, and send the correlation signal to the threshold judgment module, wherein the correlation signal is non-linear signal;
    所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理;The threshold judgment module is used to judge whether the correlation value of the received correlation signal is greater than or equal to a set value, and if so, send the correlation signal to the delay calculation module, otherwise, do not signal processing;
    所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;The delay calculation module is configured to calculate the signal of the first radio frequency link and the at least one second radio frequency link according to the correlation signal when receiving the correlation signal from the threshold judgment module The time delay between the signals of the set time slot length, and sending the time delay to the time delay alignment module;
    所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时 延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。The delay alignment module is configured to, after receiving the delay from the delay calculation module, remove the setting between the target signal and the at least one second radio frequency link according to the delay. Signals with the time delay in the signals with a fixed slot length, and removing the signals with the time delay with the target signal among the signals with a set time slot length in each second radio frequency link.
  10. 根据权利要求9所述的基站,其特征在于,所述门限判决模块,还用于:The base station according to claim 9, wherein the threshold judgment module is also used for:
    在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;When it is determined that the correlation value of the related signal is greater than or equal to the set value, instruct the lock module to respectively lock the signal of the set time slot length from the at least one second radio frequency link, and use the current The latched signal replaces the previously latched signal;
    在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。When it is determined that the correlation value of the correlation signal is smaller than the set value, instruct the lock module to stop latching the signal of the set time slot length from the at least one second radio frequency link.
  11. 一种基站,其特征在于,包括:多个射频链路、光模块、特征计算模块;其中,所述多个射频链路的数量大于或等于2;A base station, characterized by comprising: a plurality of radio frequency links, an optical module, and a feature calculation module; wherein, the number of the plurality of radio frequency links is greater than or equal to 2;
    每个射频链路,用于通过天线接收对应频段的一路信号,并对所述一路信号进行射频处理后,向所述光模块发送所述一路信号;Each radio frequency link is used to receive one signal of a corresponding frequency band through the antenna, and after performing radio frequency processing on the one signal, send the one signal to the optical module;
    所述光模块,用于对来自所述多个射频链路的多路信号进行电光转换处理,得到包含处理后的所述多路信号的光信号;其中,所述光模块中包含非线性元器件,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述至少一个第二射频链路的信号经过所述非线性元器件后生成非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠,所述光信号中还包含所述非线性失真信号;将所述光信号发送到所述中心站,接收来自所述中心站的目标信号,对所述目标信号进行光电转换处理,并将处理后的所述目标信号发送到所述特征计算模块,其中,所述目标信号包含所述第一射频链路对应的频段的信号;The optical module is configured to perform electro-optical conversion processing on the multi-channel signals from the multiple radio frequency links to obtain an optical signal including the processed multi-channel signals; wherein the optical module includes a nonlinear element A device, wherein there are a first radio frequency link and at least one second radio frequency link among the plurality of radio frequency links, and a signal of the at least one second radio frequency link generates a nonlinear distorted signal after passing through the nonlinear component, The frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link, and the optical signal also includes the nonlinear distortion signal; sending the optical signal to the central station, receiving performing photoelectric conversion processing on the target signal from the central station, and sending the processed target signal to the feature calculation module, wherein the target signal includes the first radio frequency link The signal of the corresponding frequency band;
    每个第二射频链路,还用于对接收的对应频段的一路信号进行射频处理后,将得到的信号发送到所述特征计算模块;Each second radio frequency link is also used to send the obtained signal to the feature calculation module after performing radio frequency processing on the received signal of the corresponding frequency band;
    所述特征计算模块,用于接收来自所述光模块的所述目标信号;根据所述目标信号和来自所述至少一个第二射频链路的至少一路信号计算非线性失真预测信号,并将所述非线性失真预测信号发送到所述第一射频链路,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;The feature calculation module is configured to receive the target signal from the optical module; calculate a nonlinear distortion prediction signal according to the target signal and at least one signal from the at least one second radio frequency link, and calculate the The nonlinear distortion prediction signal is sent to the first radio frequency link, wherein the nonlinear distortion prediction signal is a first prediction signal of the nonlinear distortion signal;
    所述第一射频链路,还用于根据所述非线性失真预测信号对所述第一射频链路对应频段的信号进行预失真处理以及射频处理,并向所述光模块发送处理后的信号。The first radio frequency link is further configured to perform predistortion processing and radio frequency processing on signals in the frequency band corresponding to the first radio frequency link according to the nonlinear distortion prediction signal, and send the processed signal to the optical module .
  12. 根据权利要求11所述的基站,其特征在于,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:The base station according to claim 11, wherein the feature calculation module includes an iterative calculation module, and the iterative calculation module is used for:
    根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;calculating a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear distortion characteristics of the nonlinear component;
    根据所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;calculating a target prediction signal according to at least one signal of the at least one second radio frequency link, wherein the target prediction signal is a second prediction signal of the nonlinear distortion signal;
    根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。Correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal.
  13. 根据权利要求11或12所述的基站,其特征在于,所述特征计算模块还包括滤波模块;The base station according to claim 11 or 12, wherein the feature calculation module further includes a filtering module;
    所述滤波模块,用于对所述电信号进行滤波处理,得到所述目标信号。The filtering module is configured to filter the electrical signal to obtain the target signal.
  14. 根据权利要求11~13任一所述的基站,其特征在于,所述光模块,在接收来自所述中心站的目标信号,对所述目标信号进行光电转换处理,并将处理后的所述目标信号发送 到所述特征计算模块时,具体用于:The base station according to any one of claims 11-13, wherein the optical module receives the target signal from the central station, performs photoelectric conversion processing on the target signal, and converts the processed When the target signal is sent to the feature calculation module, it is specifically used for:
    接收来自所述中心站的下行信号,对所述下行信号进行光电转换处理,并将处理后的所述下行信号发送到所述特征计算模块,其中,所述下行信号中包含所述目标信号及其它待发送给所述基站的信号;receiving a downlink signal from the central station, performing photoelectric conversion processing on the downlink signal, and sending the processed downlink signal to the feature calculation module, wherein the downlink signal includes the target signal and other signals to be sent to the base station;
    所述特征计算模块,在接收来自所述光模块的所述目标信号时,具体用于:The feature calculation module, when receiving the target signal from the optical module, is specifically used for:
    接收来自所述光模块的所述下行信号,并对所述下行信号进行滤波处理,得到所述目标信号。receiving the downlink signal from the optical module, and filtering the downlink signal to obtain the target signal.
  15. 根据权利要求11~14任一所述的基站,其特征在于,所述特征计算模块还包括反馈模块,所述反馈模块用于:The base station according to any one of claims 11-14, wherein the feature calculation module further includes a feedback module, and the feedback module is used for:
    对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。Perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link to obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  16. 根据权利要求15所述的基站,其特征在于,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;The base station according to claim 15, wherein the feedback module comprises: a lock module, a correlator, a threshold judgment module, a delay calculation module, and a delay alignment module;
    所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器;The locking module is configured to respectively latch signals with a set time slot length from the at least one second radio frequency link, and send the latched signals to the correlator;
    所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;The correlator is configured to perform correlation processing on the target signal and the signal from the lock module to obtain a correlation signal, and send the correlation signal to the threshold judgment module, wherein the correlation signal is non-linear signal;
    所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理;The threshold judgment module is used to judge whether the correlation value of the received correlation signal is greater than or equal to a set value, and if so, send the correlation signal to the delay calculation module, otherwise, do not signal processing;
    所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;The delay calculation module is configured to calculate the signal of the first radio frequency link and the at least one second radio frequency link according to the correlation signal when receiving the correlation signal from the threshold judgment module The time delay between the signals of the set time slot length, and sending the time delay to the time delay alignment module;
    所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。The delay alignment module is configured to, after receiving the delay from the delay calculation module, remove the setting between the target signal and the at least one second radio frequency link according to the delay. Signals with the time delay in the signals with a fixed slot length, and removing the signals with the time delay with the target signal among the signals with a set time slot length in each second radio frequency link.
  17. 根据权利要求16所述的基站,其特征在于,所述门限判决模块,还用于:The base station according to claim 16, wherein the threshold judgment module is also used for:
    在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;When it is determined that the correlation value of the related signal is greater than or equal to the set value, instruct the lock module to respectively lock the signal of the set time slot length from the at least one second radio frequency link, and use the current The latched signal replaces the previously latched signal;
    在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。When it is determined that the correlation value of the correlation signal is smaller than the set value, instruct the lock module to stop latching the signal of the set time slot length from the at least one second radio frequency link.
  18. 一种中心站,其特征在于,包括:光模块、信号处理模块;A central station, characterized in that it includes: an optical module, a signal processing module;
    所述光模块,用于接收来自基站的光信号后,对所述光信号进行光电转换处理得到电信号,向所述信号处理模块发送所述电信号;其中,所述电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠;The optical module is configured to perform photoelectric conversion processing on the optical signal to obtain an electrical signal after receiving the optical signal from the base station, and send the electrical signal to the signal processing module; wherein the electrical signal contains a nonlinear Distorted signals, multiple signals received by multiple radio frequency links of the base station through antennas, the number of the multiple radio frequency links is greater than or equal to 2, and the first radio frequency link and the first radio frequency link exist in the multiple radio frequency links At least one second radio frequency link, the base station includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate the nonlinear distortion signal, and the nonlinear distortion The frequency band of the signal overlaps with the frequency band corresponding to the first radio frequency link;
    所述信号处理模块,用于接收来自所述光模块的所述电信号,从所述电信号中提取所 述第一射频链路对应的频段的目标信号,并将所述目标信号发送到所述光模块;The signal processing module is configured to receive the electrical signal from the optical module, extract the target signal of the frequency band corresponding to the first radio frequency link from the electrical signal, and send the target signal to the The optical module;
    所述光模块,还用于对所述目标信号进行电光转换处理,并将处理后的所述目标信号发送到所述基站。The optical module is further configured to perform electro-optical conversion processing on the target signal, and send the processed target signal to the base station.
  19. 根据权利要求18所述的中心站,其特征在于,所述非线性失真信号的起始频率大于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:The central station according to claim 18, wherein the starting frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein:
    当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者When there is a second radio frequency link in the plurality of radio frequency links, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the Twice the cut-off frequency of the corresponding frequency band of a second radio frequency link; or
    当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。When there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the sum of the starting frequencies of the corresponding frequency bands of the two second radio frequency links, and the second frequency is the The sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, and the second frequency is the The difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  20. 根据权利要求19所述的中心站,其特征在于,The central station according to claim 19, characterized in that,
    所述信号处理模块包含滤波模块,所述滤波模块用于接收来自所述光模块的所述电信号,对所述电信号进行滤波处理,得到所述目标信号;The signal processing module includes a filtering module, the filtering module is used to receive the electrical signal from the optical module, filter the electrical signal, and obtain the target signal;
    所述光模块对所述目标信号进行电光转换处理,并将处理后的所述目标信号发送到所述基站时,具体用于:对所述目标信号和其它待发送给所述基站的信号进行电光转换处理,得到包含所述目标信号和其它待发送给所述基站的信号的下行信号,并将所述下行信号发送到所述基站。When the optical module performs electro-optical conversion processing on the target signal, and sends the processed target signal to the base station, it is specifically used to: perform the target signal and other signals to be sent to the base station Electro-optical conversion processing, obtaining a downlink signal including the target signal and other signals to be sent to the base station, and sending the downlink signal to the base station.
  21. 一种中心站,其特征在于,包括:光模块、信号处理模块、特征计算模块;A central station, characterized in that it includes: an optical module, a signal processing module, and a feature calculation module;
    所述光模块,用于接收来自至少一个基站的光信号,对所述至少一个基站中每个基站的光信号进行光电转换处理,得到每个基站的电信号;其中,任一个基站的电信号中包含非线性失真信号、所述基站的多个射频链路通过天线接收到的多路信号,所述多个射频链路的数量大于或等于2,所述多个射频链路中存在第一射频链路和至少一个第二射频链路,所述基站中包含非线性元器件,所述至少一个第二射频链路的信号经过所述非线性元器件后生成所述非线性失真信号,所述非线性失真信号的频段与所述第一射频链路对应的频段有交叠;分别将每个基站的电信号发送到所述信号处理模块和所述特征计算模块;The optical module is configured to receive an optical signal from at least one base station, perform photoelectric conversion processing on the optical signal of each base station in the at least one base station, and obtain an electrical signal of each base station; wherein, the electrical signal of any one base station Including non-linear distortion signals, multiple signals received by multiple radio frequency links of the base station through the antenna, the number of the multiple radio frequency links is greater than or equal to 2, and there is a first radio frequency link among the multiple radio frequency links A radio frequency link and at least one second radio frequency link, the base station includes nonlinear components, and the signal of the at least one second radio frequency link passes through the nonlinear components to generate the nonlinear distortion signal, so The frequency band of the nonlinear distortion signal overlaps with the frequency band corresponding to the first radio frequency link; sending the electrical signal of each base station to the signal processing module and the feature calculation module respectively;
    所述特征计算模块,用于分别接收来自所述光模块的每个基站的电信号;分别对每个基站的电信号进行特征计算处理,得到每个基站对应的非线性失真预测信号,并分别将每个基站对应的非线性失真预测信号发送到所述信号处理模块;其中,对任一个基站的电信号进行的特征计算处理包含以下步骤:从所述电信号中提取所述第一射频链路对应的频段的目标信号,以及,从所述电信号中分别提取来自所述至少一个第二射频链路的至少一路信号;根据所述目标信号和所述至少一个第二射频链路的至少一路信号计算所述非线性失真预测信号,其中,所述非线性失真预测信号为所述非线性失真信号的第一预测信号;The feature calculation module is used to respectively receive the electrical signal from each base station of the optical module; respectively perform feature calculation processing on the electrical signal of each base station to obtain a nonlinear distortion prediction signal corresponding to each base station, and respectively The nonlinear distortion prediction signal corresponding to each base station is sent to the signal processing module; wherein, the feature calculation processing on the electrical signal of any base station includes the following steps: extracting the first radio frequency chain from the electrical signal target signal in a corresponding frequency band, and at least one signal from the at least one second radio frequency link is respectively extracted from the electrical signal; according to the target signal and at least one signal of the at least one second radio frequency link Calculating the nonlinear distortion prediction signal with one signal, wherein the nonlinear distortion prediction signal is the first prediction signal of the nonlinear distortion signal;
    所述信号处理模块,用于分别接收来自所述光模块的每个基站的电信号;对所述至少一个基站的电信号进行射频处理得到目标合路信号;其中,所述目标合路信号包含所述第一射频链路对应的频段的信号;分别接收来自所述特征计算模块的每个基站对应的非线性失真预测信号;依次根据每个基站对应的非线性失真预测信号对所述目标合路信号进行失真校正处理。The signal processing module is configured to respectively receive electrical signals from each base station of the optical module; perform radio frequency processing on the electrical signals of the at least one base station to obtain a target combining signal; wherein, the target combining signal includes The signal of the frequency band corresponding to the first radio frequency link; respectively receive the nonlinear distortion prediction signal corresponding to each base station from the feature calculation module; The channel signal is processed for distortion correction.
  22. 根据权利要求21所述的中心站,其特征在于,所述非线性失真信号的起始频率大 于或等于第一频率,所述非线性失真信号的截止频率小于或等于第二频率,其中:The central station according to claim 21, wherein the start frequency of the nonlinear distortion signal is greater than or equal to the first frequency, and the cutoff frequency of the nonlinear distortion signal is less than or equal to the second frequency, wherein:
    当所述多个射频链路中存在一个第二射频链路时,所述第一频率为所述一个第二射频链路对应频段的起始频率的二倍,所述第二频率为所述一个第二射频链路对应频段的截止频率的二倍;或者When there is a second radio frequency link in the plurality of radio frequency links, the first frequency is twice the starting frequency of the frequency band corresponding to the second radio frequency link, and the second frequency is the Twice the cut-off frequency of the corresponding frequency band of a second radio frequency link; or
    当所述多个射频链路中存在两个第二射频链路时,所述第一频率为所述两个第二射频链路对应频段的起始频率之和,所述第二频率为所述两个第二射频链路对应频段的截止频率之和;或者,所述第一频率为所述两个第二射频链路对应频段的起始频率之差,所述第二频率为所述两个第二射频链路对应频段的截止频率之差。When there are two second radio frequency links in the plurality of radio frequency links, the first frequency is the sum of the starting frequencies of the corresponding frequency bands of the two second radio frequency links, and the second frequency is the The sum of the cutoff frequencies of the frequency bands corresponding to the two second radio frequency links; or, the first frequency is the difference between the start frequencies of the frequency bands corresponding to the two second radio frequency links, and the second frequency is the The difference between the cutoff frequencies of the corresponding frequency bands of the two second radio frequency links.
  23. 根据权利要求21或22所述的中心站,其特征在于,所述特征计算模块包括迭代计算模块,所述迭代计算模块用于:The central station according to claim 21 or 22, wherein the characteristic calculation module includes an iterative calculation module, and the iterative calculation module is used for:
    根据所述目标信号计算目标参数,其中,所述目标参数用于表征所述非线性元器件的非线性失真特性;calculating a target parameter according to the target signal, wherein the target parameter is used to characterize the nonlinear distortion characteristics of the nonlinear component;
    根据来自所述至少一个第二射频链路的至少一路信号计算目标预测信号,其中,所述目标预测信号为所述非线性失真信号的第二预测信号;calculating a target prediction signal according to at least one signal from the at least one second radio frequency link, wherein the target prediction signal is a second prediction signal of the nonlinear distortion signal;
    根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号。Correcting the target prediction signal according to the target parameter to obtain the nonlinear distortion prediction signal.
  24. 根据权利要求23所述的中心站,其特征在于,所述迭代计算模块,在根据所述目标信号计算目标参数时,具体用于:The central station according to claim 23, wherein the iterative calculation module, when calculating the target parameter according to the target signal, is specifically used for:
    根据设定的第一计算模型及所述目标信号,计算所述目标参数,其中,所述第一计算模型用于表示输入非线性元器件的多路信号中的一路信号、所述非线性元器件输出的与所述一路信号的频段相同的非线性失真信号与所述非线性元器件的非线性失真特性参数之间的对应关系;Calculate the target parameters according to the set first calculation model and the target signal, wherein the first calculation model is used to represent one signal among the multiple signals input to the nonlinear component, the nonlinear element The corresponding relationship between the nonlinear distortion signal output by the device and the same frequency band as the one signal and the nonlinear distortion characteristic parameters of the nonlinear component;
    所述迭代计算模块根据所述至少一个第二射频链路的至少一路信号计算目标预测信号时,具体用于:When the iterative calculation module calculates the target prediction signal according to at least one signal of the at least one second radio frequency link, it is specifically used for:
    根据设定的第二计算模型及所述至少一个第二射频链路的至少一路信号,计算所述目标预测信号,其中,所述第二计算模型用于表示经过非线性元器件的至少一路信号与所述至少一路信号经过所述非线性元器件后生成的非线性失真信号之间的对应关系。Calculate the target prediction signal according to the set second calculation model and at least one signal of the at least one second radio frequency link, wherein the second calculation model is used to represent at least one signal passing through the nonlinear component Correspondence between the at least one signal and the nonlinear distortion signal generated after the at least one signal passes through the nonlinear component.
  25. 根据权利要求23或24所述的中心站,其特征在于,所述迭代计算模块,在根据所述目标参数对所述目标预测信号进行修正,得到所述非线性失真预测信号时,具体用于:The central station according to claim 23 or 24, wherein the iterative calculation module, when correcting the target prediction signal according to the target parameters to obtain the nonlinear distortion prediction signal, is specifically used for :
    将所述目标参数与所述目标预测信号相乘,得到所述非线性失真预测信号。The target parameter is multiplied by the target prediction signal to obtain the nonlinear distortion prediction signal.
  26. 根据权利要求21~25任一所述的中心站,其特征在于,所述特征计算模块还包括滤波模块;The central station according to any one of claims 21-25, wherein the feature calculation module further includes a filtering module;
    所述滤波模块,用于对所述合路电信号进行滤波处理,得到所述目标信号。The filtering module is configured to filter the combined electrical signal to obtain the target signal.
  27. 根据权利要求21~26任一所述的中心站,其特征在于,所述特征计算模块还包括反馈模块,所述反馈模块用于:The central station according to any one of claims 21-26, wherein the feature calculation module further includes a feedback module, and the feedback module is used for:
    对所述目标信号和所述至少一个第二射频链路的至少一路信号进行时延校正处理,得到时延一致的所述目标信号和所述至少一个第二射频链路的至少一路信号。Perform delay correction processing on the target signal and at least one signal of the at least one second radio frequency link to obtain the target signal and at least one signal of the at least one second radio frequency link with consistent time delays.
  28. 根据权利要求27所述的中心站,其特征在于,所述反馈模块包括:锁数模块、相关器、门限判决模块、时延计算模块、时延对齐模块;The central station according to claim 27, wherein the feedback module comprises: a lock module, a correlator, a threshold judgment module, a time delay calculation module, and a time delay alignment module;
    所述锁数模块,用于分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并将锁存的信号发送到所述相关器;The locking module is configured to respectively latch signals with a set time slot length from the at least one second radio frequency link, and send the latched signals to the correlator;
    所述相关器,用于对所述目标信号和来自所述锁数模块的信号进行相关处理,得到相关信号,并将所述相关信号发送到所述门限判决模块,其中,所述相关信号为非线性信号;The correlator is configured to perform correlation processing on the target signal and the signal from the lock module to obtain a correlation signal, and send the correlation signal to the threshold judgment module, wherein the correlation signal is non-linear signal;
    所述门限判决模块,用于判断接收到的所述相关信号的相关值是否大于或等于设定值,若是,则将所述相关信号发送到所述时延计算模块,否则,不对所述相关信号进行处理;The threshold judgment module is used to judge whether the correlation value of the received correlation signal is greater than or equal to a set value, and if so, send the correlation signal to the delay calculation module, otherwise, do not signal processing;
    所述时延计算模块,用于在接收到来自所述门限判决模块的所述相关信号时,根据所述相关信号计算所述第一射频链路的信号和所述至少一个第二射频链路的设定时隙长度的信号之间的时延,并将所述时延发送到所述时延对齐模块;The delay calculation module is configured to calculate the signal of the first radio frequency link and the at least one second radio frequency link according to the correlation signal when receiving the correlation signal from the threshold judgment module The time delay between the signals of the set time slot length, and sending the time delay to the time delay alignment module;
    所述时延对齐模块,用于在接收到来自所述时延计算模块的所述时延后,根据所述时延,去除所述目标信号中与所述至少一个第二射频链路的设定时隙长度的信号存在所述时延的信号,以及,分别去除每个第二射频链路的设定时隙长度的信号中与所述目标信号存在所述时延的信号。The delay alignment module is configured to, after receiving the delay from the delay calculation module, remove the setting between the target signal and the at least one second radio frequency link according to the delay. Signals with the time delay in the signals with a fixed slot length, and removing the signals with the time delay with the target signal among the signals with a set time slot length in each second radio frequency link.
  29. 根据权利要求28所述的中心站,其特征在于,所述门限判决模块,还用于:The central station according to claim 28, wherein the threshold judgment module is also used for:
    在确定所述相关信号的相关值大于或等于所述设定值时,指示所述锁数模块分别锁存来自所述至少一个第二射频链路的设定时隙长度的信号,并利用当前锁存的信号替换之前已锁存的信号;When it is determined that the correlation value of the related signal is greater than or equal to the set value, instruct the lock module to respectively lock the signal of the set time slot length from the at least one second radio frequency link, and use the current The latched signal replaces the previously latched signal;
    在确定所述相关信号的相关值小于所述设定值时,指示所述锁数模块停止锁存来自所述至少一个第二射频链路的设定时隙长度的信号。When it is determined that the correlation value of the correlation signal is smaller than the set value, instruct the lock module to stop latching the signal of the set time slot length from the at least one second radio frequency link.
  30. 一种通信系统,其特征在于,包括:A communication system, characterized in that it includes:
    如权利要求1~10任一所述的基站;或者The base station according to any one of claims 1-10; or
    如权利要求11~17任一所述的基站,以及如权利要求18~20任一所述的中心站;或者The base station according to any one of claims 11-17, and the central station according to any one of claims 18-20; or
    如权利要求21~29任一所述的中心站。The central station according to any one of claims 21-29.
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