CN117118791B - Frequency offset estimation method, device, computer equipment and storage medium - Google Patents
Frequency offset estimation method, device, computer equipment and storage medium Download PDFInfo
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Abstract
The application relates to a frequency offset estimation method, a device, computer equipment and a storage medium. The method comprises the following steps: performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal; performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal; performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result; and carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value. By adopting the method, the fading caused by the channel can be reduced, the channel equalization effect is improved, the quality of the received signal is further improved, the adjustment of computing resources is saved, and the efficiency of frequency offset estimation is improved.
Description
Technical Field
The present disclosure relates to the field of communication signal processing technologies, and in particular, to a frequency offset estimation method, a device, a computer device, and a storage medium.
Background
Existing wireless communication systems employ FDD (Frequency Division Duplexing ), meaning that the uplink (mobile to base station) and downlink (base to mobile) operate on two separate frequencies (with a certain frequency spacing requirement), which operate on symmetrical frequency bands. Since carrier frequency offset in a communication system refers to carrier frequency offset of a receiving end and a transmitting end in the communication system. Carrier frequency offset (CFO, carrier Frequency Offset) is one of many non-ideal conditions that may affect the baseband receiver design. Not only can result in rotation and attenuation of the signal, but when the signal is converted to the frequency domain by fast fourier transform (Fast Fourier Transform, FFT), the frequency offset can create inter-carrier interference to the signal at each frequency point, introducing additional errors in the equalization.
In the conventional method, correlation calculation is performed based on a time domain Cyclic Prefix correlation algorithm, that is, the repeatability of CP (Cyclic Prefix) is utilized, and then frequency offset estimation is performed by utilizing a correlation calculation result. However, the estimation accuracy of the CP-CFO is not high at low signal-to-noise ratio because the CP length is short and the channel has multipath. If the accuracy needs to be improved, long accumulation iteration is needed, and power consumption and time are consumed.
Disclosure of Invention
In view of the foregoing, it is desirable to provide a frequency offset estimation method, apparatus, computer device, and computer readable storage medium that can reduce the frequency offset estimation algorithm, thereby reducing the amount of computational resources required and improving the accuracy of the frequency offset estimation.
In a first aspect, the present application provides a method for estimating a frequency offset. The method comprises the following steps:
performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal;
performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal;
performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result;
and carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value.
In one embodiment, performing time-frequency conversion operation according to a received time-domain pilot signal to obtain a target frequency-domain primary synchronization signal and a target frequency-domain secondary synchronization signal, including:
reading a time domain primary synchronization signal and a time domain secondary synchronization signal from a time domain pilot signal;
and performing time-frequency conversion on the time domain primary synchronization signal and the time domain secondary synchronization signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
In one embodiment, performing channel processing according to a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal, including:
performing channel estimation on the target frequency domain main synchronous signal to obtain a target channel estimation value;
and carrying out equalization operation according to the target channel estimation value and the target frequency domain auxiliary synchronous signal to obtain an auxiliary synchronous equalization signal.
In one embodiment, performing a correlation operation according to the secondary synchronization equalization signal and the local secondary synchronization signal to obtain a correlation operation result, including:
performing accumulation operation on the auxiliary synchronous equalization signals to obtain an accumulation equalization result;
and performing correlation operation according to the accumulated equalization result and the local auxiliary synchronous signal to obtain a correlation operation result.
In one embodiment, performing an accumulation operation on the secondary synchronization equalization signal to obtain an accumulation equalization result includes:
dividing the auxiliary synchronous equalization signal according to half frames to obtain a first half frame and a second half frame;
performing phase compensation on the second field to obtain a compensated second field;
and carrying out weighted superposition on the first half frame and the compensated second half frame to obtain an accumulated balance result.
In one embodiment, performing a correlation operation according to the accumulated equalization result and the local secondary synchronization signal to obtain a correlation operation result, including:
acquiring a pre-generated local auxiliary synchronous signal;
multiplying the local auxiliary synchronous signal and the accumulated equalization result by corresponding frequency points to obtain a frequency domain correlation result;
and carrying out summation operation on the frequency domain correlation result to obtain a correlation operation result.
In one embodiment, performing frequency offset estimation according to a correlation operation result to obtain a target frequency offset estimation value includes:
peak value searching is carried out on the correlation operation result, and the peak value position after searching and the corresponding amplitude are obtained;
carrying out data extraction according to the searched peak value position to obtain phase quadrature modulation data with the maximum correlation value;
and calculating to obtain a target frequency offset estimated value based on the phase quadrature modulation data.
In a second aspect, the present application further provides a frequency offset estimation device. The device comprises:
the signal receiving module is used for performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain main synchronous signal and a target frequency domain auxiliary synchronous signal;
the channel processing module is used for carrying out channel processing according to the target frequency domain main synchronous signal and the target frequency domain auxiliary synchronous signal to obtain an auxiliary synchronous balanced signal;
the correlation operation module is used for carrying out correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result;
and the frequency offset estimation module is used for carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value.
In a third aspect, the present application also provides a computer device. The computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor realizes the following steps when executing the computer program:
performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal;
performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal;
performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result;
and carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value.
In a fourth aspect, the present application also provides a computer-readable storage medium. The computer readable storage medium having stored thereon a computer program which when executed by a processor performs the steps of:
performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal;
performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal;
performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result;
and carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value.
The frequency offset estimation method, the device, the computer equipment and the storage medium are used for reading the main synchronization signal and the auxiliary synchronization signal from the received time domain pilot signal, performing time-frequency conversion on the main synchronization signal and the auxiliary synchronization signal, further obtaining the frequency domain main synchronization signal and the frequency domain auxiliary synchronization signal, calculating channel estimation by using the frequency domain main synchronization signal, carrying out channel equalization on the frequency domain auxiliary synchronization signal, carrying out correlation operation by multi-half frame accumulation operation and using the local auxiliary synchronization signal to obtain correlation operation results, carrying out peak value search on the correlation operation results and carrying out frequency offset estimation based on the peak value search results, reducing fading caused by channels and improving the quality of the received signals, carrying out peak value search on the correlation operation results, and simultaneously carrying out phase quadrature modulation data calculation based on the maximum correlation value to obtain frequency offset, thereby saving the modulation of calculation resources and improving the efficiency of frequency offset estimation.
Drawings
FIG. 1 is a flow chart of a method for estimating frequency offset according to an embodiment;
FIG. 2 is a flow chart of frequency offset estimation according to one embodiment;
FIG. 3 is a block diagram of an embodiment of a frequency offset estimation device;
fig. 4 is an internal structural diagram of a computer device in one embodiment.
Description of the embodiments
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.
In one embodiment, as shown in fig. 1, a frequency offset estimation method is provided, where the method is applied to a terminal to illustrate the method, it is understood that the method may also be applied to a server, and may also be applied to a system including the terminal and the server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the steps of:
step 102, performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
Wherein the time domain pilot signal is a pilot signal in an LTE (Long Term Evolution ) system for channel estimation and compensation; the time domain pilot signal includes a primary synchronization signal and a secondary synchronization signal.
Specifically, when the receiving device acquires the time domain pilot signal, the primary synchronization signal and the secondary synchronization signal are read from the time domain pilot signal, and then the primary synchronization signal and the secondary synchronization signal are respectively transmitted to an FFT (fast fourier transform ) module for time-frequency conversion, so as to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
And 104, performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal.
The channel processing refers to processing and technology involved in transmitting and receiving signals in a wireless communication system, and the channel processing includes channel estimation and channel equalization.
Specifically, the frequency domain characteristics of the target frequency domain primary synchronization signal are extracted by using the processed target frequency domain primary synchronization signal, frequency offset compensation and frequency response estimation are performed by combining the pre-generated local primary synchronization signal, so as to obtain a frequency offset estimation result, and then channel equalization operation is performed by using the frequency offset estimation result and the target frequency domain secondary synchronization signal, so as to obtain a secondary synchronization equalization signal
And 106, performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result.
Specifically, a local frequency domain auxiliary synchronization signal is determined based on a pre-generated local auxiliary synchronization signal, and correlation calculation is performed on the auxiliary synchronization equalization signal and the local frequency domain auxiliary synchronization signal, so that a correlation operation result is obtained.
And step 108, performing frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value.
Specifically, after the correlation operation result is obtained, peak value search is carried out on the correlation operation result, peak value data and corresponding positions in the correlation operation result are obtained, target data are extracted, phase quadrature modulation data of the maximum correlation value in the target data are determined, and frequency offset is estimated according to the phase quadrature modulation data of the maximum correlation value.
In the frequency offset estimation method, the primary synchronization signal and the secondary synchronization signal are read from the received time domain pilot signal, the primary synchronization signal and the secondary synchronization signal are subjected to time-frequency conversion, so that the frequency domain primary synchronization signal and the frequency domain secondary synchronization signal are obtained, the frequency domain primary synchronization signal is utilized to calculate the channel estimation, then the frequency domain secondary synchronization signal is subjected to channel equalization, then the correlation operation result is obtained through multi-half frame accumulation operation and correlation operation by utilizing the local secondary synchronization signal, the peak value search is carried out on the correlation operation result, the frequency offset estimation is carried out on the correlation operation result on the basis of the peak value search result, the fading caused by the channel is reduced, the channel equalization effect is improved, the quality of the received signal is improved, the frequency offset is obtained through the peak value search on the correlation operation result, and the frequency offset is calculated and obtained on the basis of the phase quadrature modulation data of the maximum correlation value.
In one embodiment, performing a time-frequency conversion operation according to a received time-domain pilot signal to obtain a target frequency-domain primary synchronization signal and a target frequency-domain secondary synchronization signal, including:
reading a time domain primary synchronization signal and a time domain secondary synchronization signal from a time domain pilot signal; and performing time-frequency conversion on the time domain primary synchronization signal and the time domain secondary synchronization signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
Specifically, the signal reading is performed from the obtained time domain pilot signal to obtain the required signals, namely the time domain primary synchronization signal and the time domain secondary synchronization signal, and then the required signals are transmitted to the FFT module, and the FFT module performs Fourier transform to convert the time domain signals into frequency domain signals.
In this embodiment, the time-frequency conversion is performed on the time-domain pilot signal by using the FFT module to obtain the frequency-domain primary synchronization signal and the frequency-domain secondary synchronization signal, so that the frequency characteristics and the frequency-domain information of the converted frequency-domain primary synchronization signal and the converted frequency-domain secondary synchronization signal are known more deeply, and the subsequent channel estimation on the frequency-domain primary synchronization signal and the channel equalization operation by combining the frequency-domain secondary synchronization signal are facilitated, so that the effect of improving the frequency-domain secondary synchronization signal can be achieved
In one embodiment, performing channel processing according to a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal, including:
the channel processing refers to processing and technology involved in transmitting and receiving signals in a wireless communication system, the channel processing comprises channel estimation and channel equalization, and the channel estimation adopts an LS channel estimation algorithm.
Performing channel estimation on the target frequency domain main synchronous signal to obtain a target channel estimation value; and carrying out equalization operation according to the target channel estimation value and the target frequency domain auxiliary synchronous signal to obtain an auxiliary synchronous equalization signal.
Specifically, after the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal are obtained from the FFT module, the target frequency domain primary synchronization signal is transmitted to the channel estimation unit, and a preset LS channel estimation algorithm is used to perform a channel estimation operation on the target frequency domain primary synchronization signal to obtain a target channel estimation value, that is, to estimate the frequency response of the channel. And then, carrying out channel equalization operation by combining the target frequency domain auxiliary synchronous signal output by the FFT module to obtain a channel equalization result.
In this embodiment, by performing channel estimation based on the FFT module output target frequency domain primary synchronization signal and performing channel equalization in combination with the target frequency domain secondary synchronization signal after obtaining the target channel estimation, correction of channel distortion and interference is achieved, and thus signal receiving performance and data transmission quality are improved.
In one embodiment, performing a correlation operation according to the secondary synchronization equalization signal and the local secondary synchronization signal to obtain a correlation operation result, including:
performing accumulation operation on the auxiliary synchronous equalization signals to obtain an accumulation equalization result; and performing correlation operation according to the accumulated equalization result and the local auxiliary synchronous signal to obtain a correlation operation result.
The accumulation operation refers to that the received signal is accumulated and averaged at a plurality of moments, and the accumulation operation adopts multi-field accumulation.
Specifically, after the channel processing operation based on the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal is completed, multi-field accumulating operation is performed on the channel equalization result, the equalized frame signal is divided into two fields, and compensation and weighted superposition are performed based on the two fields to obtain a multi-field accumulating result, namely an accumulating equalization result. And meanwhile, a local frequency domain auxiliary synchronous signal is obtained based on the pre-generated local auxiliary synchronous signal, and the local frequency domain auxiliary synchronous signal and the accumulated equalization result are utilized to perform correlation calculation on the frequency domain, so that a correlation operation result on the frequency domain is obtained.
In this embodiment, by performing a multi-frame accumulation operation on the channel equalization result, the signal-to-noise ratio of the signal is improved, so as to improve the signal quality, and performing a correlation operation based on the accumulated equalization result, the accuracy and stability of channel estimation can be improved, and the estimation deviation is reduced, so that the recovery of the signal affected by the channel is facilitated.
In one embodiment, performing an accumulation operation on the secondary synchronization equalization signal to obtain an accumulation equalization result includes:
dividing the auxiliary synchronous equalization signal according to half frames to obtain a first half frame and a second half frame; performing phase compensation on the second field to obtain a compensated second field; and carrying out weighted superposition on the first half frame and the compensated second half frame to obtain an accumulated balance result.
Wherein the first half frame and the second half frame refer to two adjacent half frames.
Specifically, the auxiliary synchronous equalization signal is divided according to half frames to obtain a plurality of continuous half frames, the signal of each half frame is accumulated to obtain a half frame accumulation result, and the adjacent half frame accumulation results are weighted and overlapped to obtain an accumulation equalization result.
In this embodiment, by performing a multi-field accumulation operation on the auxiliary synchronous equalization signal after the equalization operation is completed, the signal quality is improved, multipath interference is reduced, and anti-interference capability is improved, so that the accuracy of the result obtained by calculating the equalization accumulation result is improved.
In one embodiment, performing a correlation operation according to the accumulated equalization result and the local secondary synchronization signal to obtain a correlation operation result, including:
acquiring a pre-generated local auxiliary synchronous signal; multiplying the local auxiliary synchronous signal and the accumulated equalization result by corresponding frequency points to obtain a frequency domain correlation result; and carrying out summation operation on the frequency domain correlation result to obtain a correlation operation result.
Specifically, a local frequency domain auxiliary synchronization signal is obtained based on a pre-generated local auxiliary synchronization signal, and a correlation calculation on a frequency domain is performed by utilizing the local frequency domain auxiliary synchronization signal and an accumulated equalization result, so that a correlation calculation result on the frequency domain is obtained.
In this embodiment, by calculating the correlation with the local secondary synchronization signal using the accumulated equalization result, distortion and interference caused by the channel are reduced, and thus the quality and reliability of the signal are improved.
In one embodiment, performing frequency offset estimation according to a correlation operation result to obtain a target frequency offset estimation value, including:
peak value searching is carried out on the correlation operation result, and the peak value position after searching and the corresponding amplitude are obtained; carrying out data extraction according to the searched peak value position to obtain phase quadrature modulation data with the maximum correlation value; and calculating to obtain a target frequency offset estimated value based on the phase quadrature modulation data.
Specifically, after the correlation operation result is obtained, peak value search is carried out on the correlation operation result, peak value data and corresponding positions in the correlation operation result are obtained, target data are extracted, phase quadrature modulation data of the maximum correlation value in the target data are determined, and frequency offset is estimated according to the phase quadrature modulation data of the maximum correlation value.
In this embodiment, the data of the secondary synchronization signal sequence position is obtained in the correlation operation by using the local secondary synchronization signal, so as to obtain IQ (in-phase) data with the maximum correlation value, i.e. phase quadrature modulation data, so as to complete the frequency offset estimation, directly calculate the frequency offset in the process of detecting the secondary synchronization signal, and save the power consumption and the time without additionally calculating the frequency offset.
In one embodiment, as shown in fig. 2, a frequency offset estimation method is provided, which includes the following steps:
reading a time domain pilot signal; performing time-frequency conversion on the time domain pilot frequency signal to obtain a frequency domain main synchronous signal and a frequency domain auxiliary synchronous signal; carrying out channel estimation by utilizing the frequency domain main synchronous signal to obtain a channel estimation result; performing equalization operation based on the channel estimation result and the frequency domain auxiliary synchronous signal to obtain an equalization operation result; performing multi-frame accumulation by using the equalization operation result to obtain an equalization accumulation result; performing correlation operation based on the local frequency domain auxiliary synchronous signal and the balanced accumulation result to obtain a correlation operation result; and carrying out frequency offset estimation based on the correlation operation result to obtain a target frequency offset estimation value.
Specifically, after the time domain pilot signal is read, time-frequency conversion is performed, and the conversion formula is as follows:
wherein the method comprises the steps ofFor the Fourier transform algorithm, SSS is the secondary synchronization signal,/->Is a frequency domain auxiliary synchronous signal, PSS is a main synchronous signal,>is a frequency domain primary synchronization signal.
The channel estimation is carried out on the frequency domain main synchronous signal, and the specific formula is as follows:
wherein,for the channel estimation result, +.>Is conjugate algorithm->Is a local frequency domain primary synchronization signal.
And carrying out equalization operation based on a channel estimation result and the frequency domain auxiliary synchronous signal, wherein the specific formula is as follows:
wherein,is the result of the equalization operation.
And carrying out correlation operation based on the local frequency domain auxiliary synchronous signal and the balanced accumulation result, wherein the specific formula is as follows:
wherein corr is the result of the correlation operation,is a local frequency domain secondary synchronization signal.
Peak value searching is carried out on the related operation result, frequency offset estimation is carried out based on the search result, and the specific formula is as follows:
wherein cfo is a frequency offset estimation value,for phase calculation algorithm +.>IQ data with the largest correlation value.
In this embodiment, a primary synchronization signal and a secondary synchronization signal are read from a received time domain pilot signal, the primary synchronization signal and the secondary synchronization signal are subjected to time-frequency conversion, so that a frequency domain primary synchronization signal and a frequency domain secondary synchronization signal are obtained, channel estimation is calculated by using the frequency domain primary synchronization signal, then the frequency domain secondary synchronization signal is subjected to channel equalization, then a correlation operation result is obtained by multi-half frame accumulation operation and correlation operation by using a local secondary synchronization signal, peak value search is performed on the correlation operation result, frequency offset estimation is performed on the basis of the peak value search result, and when signal processing is performed on the basis of the primary synchronization signal and the secondary synchronization signal, fading caused by a channel is reduced, the channel equalization effect is improved, the quality of the received signal is further improved, and frequency offset is obtained by performing peak value search on the correlation operation result, and meanwhile, the frequency offset is obtained by calculating phase quadrature modulation data on the basis of a maximum correlation value, so that the modulation of calculation resources is saved, and the frequency offset estimation efficiency is improved.
It should be understood that, although the steps in the flowcharts related to the embodiments described above are sequentially shown as indicated by arrows, these steps are not necessarily sequentially performed in the order indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least some of the steps in the flowcharts described in the above embodiments may include a plurality of steps or a plurality of stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of the steps or stages is not necessarily performed sequentially, but may be performed alternately or alternately with at least some of the other steps or stages.
Based on the same inventive concept, the embodiment of the application also provides a frequency offset estimation device for realizing the above related frequency offset estimation method. The implementation scheme of the solution to the problem provided by the apparatus is similar to the implementation scheme described in the above method, so the specific limitation in the embodiments of the one or more frequency offset estimation apparatuses provided below may be referred to the limitation of the frequency offset estimation method hereinabove, and will not be repeated here.
In one embodiment, as shown in fig. 3, there is provided a frequency offset estimation apparatus, including: a signal receiving module 302, a channel processing module 304, a correlation operation module 306, and a frequency offset estimation module 308, wherein:
the signal receiving module 302 is configured to perform a time-frequency conversion operation according to the received time-domain pilot signal, so as to obtain a target frequency-domain primary synchronization signal and a target frequency-domain secondary synchronization signal.
The channel processing module 304 is configured to perform channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal, and obtain a secondary synchronization equalization signal.
And the correlation operation module 306 is configured to perform correlation operation according to the secondary synchronization equalization signal and the local secondary synchronization signal, so as to obtain a correlation operation result.
The frequency offset estimation module 308 is configured to perform frequency offset estimation according to the correlation operation result, and obtain a target frequency offset estimation value.
In one embodiment, the signal receiving module 302 is further configured to read a time domain primary synchronization signal and a time domain secondary synchronization signal from the time domain pilot signal; and performing time-frequency conversion on the time domain primary synchronization signal and the time domain secondary synchronization signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
In one embodiment, the channel processing module 304 is further configured to perform channel estimation on the target frequency domain primary synchronization signal to obtain a target channel estimation value; and carrying out equalization operation according to the target channel estimation value and the target frequency domain auxiliary synchronous signal to obtain an auxiliary synchronous equalization signal.
In one embodiment, the correlation operation module 306 is further configured to perform an accumulation operation on the secondary synchronization equalization signal to obtain an accumulation equalization result; and performing correlation operation according to the accumulated equalization result and the local auxiliary synchronous signal to obtain a correlation operation result.
In one embodiment, the correlation operation module 306 is further configured to divide the secondary synchronization equalization signal according to a field to obtain a first field and a second field; performing phase compensation on the second field to obtain a compensated second field; and carrying out weighted superposition on the first half frame and the compensated second half frame to obtain an accumulated balance result.
In one embodiment, the correlation operation module 306 is further configured to obtain a pre-generated local secondary synchronization signal; multiplying the local auxiliary synchronous signal and the accumulated equalization result by corresponding frequency points to obtain a frequency domain correlation result; and carrying out summation operation on the frequency domain correlation result to obtain a correlation operation result.
In one embodiment, the frequency offset estimation module 308 is further configured to perform peak search on the correlation operation result, to obtain a peak position after search and a corresponding amplitude thereof; carrying out data extraction according to the searched peak value position to obtain phase quadrature modulation data with the maximum correlation value; and calculating to obtain a target frequency offset estimated value based on the phase quadrature modulation data.
The above-mentioned various modules in the frequency offset estimation device may be implemented in whole or in part by software, hardware, and combinations thereof. The above modules may be embedded in hardware or may be independent of a processor in the computer device, or may be stored in software in a memory in the computer device, so that the processor may call and execute operations corresponding to the above modules.
In one embodiment, a computer device is provided, which may be a server, the internal structure of which may be as shown in fig. 4. The computer device includes a processor, a memory, an Input/Output interface (I/O) and a communication interface. The processor, the memory and the input/output interface are connected through a system bus, and the communication interface is connected to the system bus through the input/output interface. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database of the computer device is used for storing the primary synchronization signal and the secondary synchronization signal data. The input/output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a method of frequency offset estimation.
Those skilled in the art will appreciate that the structures shown in FIG. 4 are block diagrams only and do not constitute a limitation of the computer device on which the present aspects apply, and that a particular computer device may include more or less components than those shown, or may combine some of the components, or have a different arrangement of components.
In an embodiment, there is also provided a computer device comprising a memory and a processor, the memory having stored therein a computer program, the processor implementing the steps of the method embodiments described above when the computer program is executed.
In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored which, when executed by a processor, carries out the steps of the method embodiments described above.
It should be noted that, the user information (including, but not limited to, user equipment information, user personal information, etc.) and the data (including, but not limited to, data for analysis, stored data, presented data, etc.) referred to in the present application are information and data authorized by the user or sufficiently authorized by each party, and the collection, use and processing of the related data are required to comply with the related laws and regulations and standards of the related countries and regions.
Those skilled in the art will appreciate that implementing all or part of the above described methods may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed, may comprise the steps of the embodiments of the methods described above. Any reference to memory, database, or other medium used in the various embodiments provided herein may include at least one of non-volatile and volatile memory. The nonvolatile Memory may include Read-Only Memory (ROM), magnetic tape, floppy disk, flash Memory, optical Memory, high density embedded nonvolatile Memory, resistive random access Memory (ReRAM), magnetic random access Memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric Memory (Ferroelectric Random Access Memory, FRAM), phase change Memory (Phase Change Memory, PCM), graphene Memory, and the like. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, and the like. By way of illustration, and not limitation, RAM can be in the form of a variety of forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), and the like. The databases referred to in the various embodiments provided herein may include at least one of relational databases and non-relational databases. The non-relational database may include, but is not limited to, a blockchain-based distributed database, and the like. The processors referred to in the embodiments provided herein may be general purpose processors, central processing units, graphics processors, digital signal processors, programmable logic units, quantum computing-based data processing logic units, etc., without being limited thereto.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the present application. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application shall be subject to the appended claims.
Claims (10)
1. A method for frequency offset estimation, the method comprising:
performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal;
performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal;
performing correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result;
performing frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value;
wherein, the performing correlation operation according to the auxiliary synchronization equalization signal and the local auxiliary synchronization signal to obtain a correlation operation result includes:
performing accumulation operation on the auxiliary synchronous equalization signals to obtain an accumulation equalization result;
performing correlation operation according to the accumulated equalization result and the local auxiliary synchronous signal to obtain a correlation operation result;
the step of performing frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value comprises the following steps:
peak value searching is carried out on the correlation operation result, and the peak value position after searching and the corresponding amplitude are obtained;
extracting data according to the searched peak value position to obtain phase quadrature modulation data with the maximum correlation value;
calculating to obtain a target frequency offset estimated value based on the phase quadrature modulation data;
reading a time domain pilot signal; performing time-frequency conversion on the time domain pilot frequency signal to obtain a frequency domain main synchronous signal and a frequency domain auxiliary synchronous signal; carrying out channel estimation by utilizing the frequency domain main synchronous signal to obtain a channel estimation result; performing equalization operation based on the channel estimation result and the frequency domain auxiliary synchronous signal to obtain an equalization operation result; performing multi-frame accumulation by using the equalization operation result to obtain an equalization accumulation result; performing correlation operation based on the local frequency domain auxiliary synchronous signal and the balanced accumulation result to obtain a correlation operation result; and carrying out frequency offset estimation based on the correlation operation result to obtain a target frequency offset estimation value.
2. The method of claim 1, wherein the performing a time-frequency conversion operation according to the received time-domain pilot signal to obtain the target frequency-domain primary synchronization signal and the target frequency-domain secondary synchronization signal comprises:
reading a time domain primary synchronization signal and a time domain secondary synchronization signal from the time domain pilot signal;
and performing time-frequency conversion on the time domain primary synchronization signal and the time domain secondary synchronization signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
3. The method of claim 1, wherein the performing channel processing according to the target frequency domain primary synchronization signal and the target frequency domain secondary synchronization signal to obtain a secondary synchronization equalization signal comprises:
performing channel estimation on the target frequency domain main synchronous signal to obtain a target channel estimation value;
and carrying out equalization operation according to the target channel estimation value and the target frequency domain auxiliary synchronization signal to obtain an auxiliary synchronization equalization signal.
4. The method of claim 1, wherein the performing the accumulating operation on the secondary synchronization equalization signal to obtain an accumulated equalization result comprises:
dividing the auxiliary synchronous equalization signal according to half frames to obtain a first half frame and a second half frame;
performing phase compensation on the second field to obtain a compensated second field;
and carrying out weighted superposition on the first half frame and the compensated second half frame to obtain an accumulated balance result.
5. The method according to claim 1, wherein the performing a correlation operation according to the accumulated equalization result and the local secondary synchronization signal to obtain a correlation operation result includes:
acquiring a pre-generated local auxiliary synchronous signal;
multiplying the local auxiliary synchronous signal and the accumulated equalization result by corresponding frequency points to obtain a frequency domain correlation result;
and carrying out summation operation on the frequency domain correlation result to obtain a correlation operation result.
6. A frequency offset estimation apparatus, the apparatus comprising:
the signal receiving module is used for performing time-frequency conversion operation according to the received time domain pilot signal to obtain a target frequency domain main synchronous signal and a target frequency domain auxiliary synchronous signal;
the channel processing module is used for carrying out channel processing according to the target frequency domain main synchronous signal and the target frequency domain auxiliary synchronous signal to obtain an auxiliary synchronous balanced signal;
the correlation operation module is used for carrying out correlation operation according to the auxiliary synchronous equalization signal and the local auxiliary synchronous signal to obtain a correlation operation result; the method is also used for carrying out accumulation operation on the auxiliary synchronous equalization signals to obtain accumulation equalization results; performing correlation operation according to the accumulated equalization result and the local auxiliary synchronous signal to obtain a correlation operation result;
the frequency offset estimation module is used for carrying out frequency offset estimation according to the correlation operation result to obtain a target frequency offset estimation value; the method is also used for carrying out peak value search on the correlation operation result to obtain the searched peak value position and the corresponding amplitude thereof; extracting data according to the searched peak value position to obtain phase quadrature modulation data with the maximum correlation value; and calculating to obtain a target frequency offset estimated value based on the phase quadrature modulation data.
7. The apparatus of claim 6, wherein the signal receiving module is further configured to read a time domain primary synchronization signal and a time domain secondary synchronization signal from the time domain pilot signal; and performing time-frequency conversion on the time domain primary synchronization signal and the time domain secondary synchronization signal to obtain a target frequency domain primary synchronization signal and a target frequency domain secondary synchronization signal.
8. The apparatus of claim 6, wherein the channel processing module is further configured to perform channel estimation on the target frequency domain primary synchronization signal to obtain a target channel estimation value; and carrying out equalization operation according to the target channel estimation value and the target frequency domain auxiliary synchronization signal to obtain an auxiliary synchronization equalization signal.
9. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any one of claims 1 to 5 when the computer program is executed.
10. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 5.
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