WO2020088508A1

WO2020088508A1 - Signal processing method and apparatus

Info

Publication number: WO2020088508A1
Application number: PCT/CN2019/114295
Authority: WO
Inventors: 毛凌; 李建平; 江立红; 杨少委
Original assignee: 华为技术有限公司
Priority date: 2018-11-01
Filing date: 2019-10-30
Publication date: 2020-05-07
Also published as: CN111130682A; CN111130682B

Abstract

Disclosed in the embodiments of the present application are a signal processing method and apparatus, relating to the field of communications, and solving the problem of how to reduce adjacent channel interference caused by an access link on a backhaul link without changing the structure of a device. The specific solution is as follows: a backhaul node receiving an adjacent channel interference signal within a first frequency band, and acquiring an adjacent channel interference reference signal, the first frequency band being a frequency band used by the backhaul node to receive a downlink signal, the adjacent channel interference signal including an intermodulation component within the first frequency band, the intermodulation component within the first frequency band being obtained by the access node after performing baseband processing, digital and analog processing and power amplification on a received first downlink signal, the adjacent channel interference reference signal including the intermodulation component within the first frequency band; performing adjacent channel interference cancellation processing on the adjacent channel interference signal according to the adjacent channel interference reference signal, to obtain the signal on which the adjacent channel interference cancellation has been performed. Thus, the present invention reduces the adjacent channel interference caused by the access link on the backhaul link. The embodiments of the present application are applied to signal processing processes.

Description

Signal processing method and device

This application requires the priority of the Chinese patent application filed on November 01, 2018, with the application number 201811295447.0 and the application name "a signal processing method and device", the entire content of which is incorporated by reference in this application in.

Technical field

Embodiments of the present application relate to the field of communications, and in particular, to a signal processing method and device.

Background technique

Relay (relay) technology refers to adding one or more relay nodes between the network device and the terminal device, which is responsible for forwarding the wireless signal one or more times, replacing a poor quality link with two quality Better links to expand link capacity and network coverage and improve edge user experience. For example, a link between a network device and a terminal device is divided into two links, that is, a link between the network device and the relay station and a link between the relay station and the terminal device. The link between the relay station and the terminal device may be referred to as an access link. The link between the network device and the relay station may be referred to as a backhaul link.

An important problem that needs to be solved for the relay technology is to reduce the adjacent-frequency interference generated by the access link to the backhaul link. In the prior art, the backhaul link and the access link can multiplex the same carrier frequency resource to work simultaneously, and adopt analog and digital cancellation methods to reduce adjacent frequency interference. Although the use of analog and digital cancellation methods can reduce adjacent frequency interference, it is necessary to design complex analog cancellation modules. For the relay nodes, additional RF signal interfaces and external connection cables need to be added to connect the network equipment The transmitted radio frequency signal is transmitted to the relay module of the relay node, so that the relay module cannot be connected to the existing RRU module, which increases the deployment cost.

Summary of the invention

The embodiments of the present application provide a signal processing method and device, which solve the problem of how to reduce the adjacent-frequency interference caused by the access link to the backhaul link without changing the device structure.

To achieve the above purpose, the embodiments of the present application adopt the following technical solutions:

In a first aspect, an embodiment of the present application provides a signal processing method that can be applied to a backhaul node, or the method can be applied to a communication device that can support the backhaul node to implement the method, for example, the communication device includes a chip system The method includes: the backhaul node receives the adjacent frequency interference signal in the first frequency band, and after acquiring the adjacent frequency interference reference signal, performs adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal to obtain adjacent frequency interference Signal after cancellation. Among them, the first frequency band is the frequency band used by the backhaul node to receive the downlink signal. The adjacent frequency interference signal includes the intermodulation component in the first frequency band. The intermodulation component in the first frequency band is the first signal received by the access node. The line signal is obtained after baseband processing, digital and analog processing and power amplification. The signal processing method provided by the embodiment of the present application realizes that the adjacent channel interference reference signal is acquired through the reference channel without changing the device structure, and the adjacent channel interference signal is processed according to the adjacent channel interference reference signal. Therefore, the adjacent-channel interference generated by the access link to the backhaul link is effectively reduced.

With reference to the first aspect, in a possible implementation manner, the backhaul node may receive the first adjacent channel interference reference signal transmitted by the access node, where the first adjacent channel interference reference signal is the access node's mode for the second downlink signal The digitally converted signal, the first adjacent-channel interference reference signal also includes intermodulation components outside the first frequency band, and the second downlink signal is the access node that performs baseband processing, digital and analog processing on the received first downlink signal. Obtained after power amplification.

Further, after receiving the first adjacent channel interference reference signal transmitted by the access node, the method further includes: obtaining a second adjacent channel interference reference signal from the first adjacent channel interference reference signal according to the first frequency band. Thus, the performance of performing adjacent channel interference cancellation processing on adjacent channel interference signals is improved.

With reference to the first aspect, in another possible implementation manner, the adjacent-channel interference reference signal is a second adjacent-channel interference reference signal, and acquiring the adjacent-channel interference reference signal includes: the backhaul node receives the second neighbor transmitted by the access node Frequency interference reference signal, the second adjacent frequency interference reference signal is the signal after the access node performs analog-to-digital conversion and filtering on the second downlink signal, and the second downlink signal is the access node that passes the baseband to the received first downlink signal After processing, digital and analog processing and power amplification.

With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, adjacent-frequency interference cancellation processing is performed on the adjacent-frequency interference signal according to the adjacent-frequency interference reference signal to obtain the adjacent-frequency interference cancellation signal, including : Obtain the i-th adjacent channel interference image signal according to the i-th adjacent channel interference reference signal and the i-th coefficient, the i-th coefficient is determined by the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference cancellation signal , Where i is an integer, the value of i is 2 to N, N is an integer, the signal after the first adjacent frequency interference cancellation is the first adjacent frequency interference image signal to perform the adjacent frequency interference cancellation on the first adjacent frequency interference signal The processing determines that the first adjacent-channel interference image signal is determined by the first adjacent-channel interference reference signal and the initial value of the coefficient; the adjacent-channel interference cancellation process is performed on the i-th adjacent-channel interference signal according to the i-th adjacent-channel interference image signal to obtain the i The signal after the adjacent frequency interference cancellation.

In addition, before receiving the adjacent channel interference signal in the first frequency band, the method further includes: transmitting the first downlink signal to the access node.

In a second aspect, an embodiment of the present application provides a signal processing method that can be applied to an access node, or that the method can be applied to a communication device that can support the access node to implement the method, for example, the communication device includes a chip system The method includes: after receiving the first downlink signal, the access node performs baseband processing, digital and analog processing, and power amplification on the first downlink signal to obtain a second downlink signal including intermodulation components in the first frequency band, And send a second downlink signal to the terminal device, and acquire the adjacent channel interference reference signal according to the second downlink signal, and transmit the adjacent channel interference reference signal to the backhaul node. The adjacent frequency interference reference signal includes intermodulation components in the first frequency band. The signal processing method provided by the embodiment of the present application realizes that the adjacent channel interference reference signal is acquired through the reference channel without changing the device structure, and the adjacent channel interference signal is processed according to the adjacent channel interference reference signal. Therefore, the adjacent-channel interference generated by the access link to the backhaul link is effectively reduced.

With reference to the second aspect, in a possible implementation manner, the adjacent-channel interference reference signal is a first adjacent-channel interference reference signal, and obtaining the adjacent-channel interference reference signal according to the second downlink signal includes: performing modulus on the second downlink signal After conversion, a first adjacent-channel interference reference signal is obtained, and the first adjacent-channel interference reference signal further includes intermodulation components outside the first frequency band.

With reference to the second aspect, in another possible implementation manner, the adjacent-channel interference reference signal is a second adjacent-channel interference reference signal, and obtaining the adjacent-channel interference reference signal according to the second downlink signal includes: modulating the second downlink signal Digital conversion to obtain a first adjacent-channel interference reference signal, the first adjacent-channel interference reference signal also includes intermodulation components outside the first frequency band; a second adjacent-channel interference reference is obtained from the first adjacent-channel interference reference signal according to the first frequency band signal.

With reference to the first aspect and the foregoing possible implementation manners, in another possible implementation manner, before performing baseband processing, digital and analog processing, and power amplification on the first downlink signal to obtain the second downlink signal, the method further includes : Receive the first downlink signal transmitted by the return node.

Optionally, to increase the signal-to-noise ratio of the adjacent channel interference reference signal and improve the adjacent channel interference cancellation performance, before acquiring the adjacent channel interference reference signal according to the second downlink signal, the method further includes: suppressing the adjacent channel interference reference signal The main signal is the service signal included in the second downlink signal.

In a third aspect, an embodiment of the present application further provides a signal processing apparatus, which is used to implement the method described in the first aspect above. The signal processing device is a backhaul node or a communication device that supports the backhaul node to implement the method described in the first aspect, for example, the communication device includes a chip system. For example, the signal processing device includes: a receiving unit and a processing unit. The receiving unit is configured to receive an adjacent frequency interference signal in a first frequency band. The first frequency band is a frequency band used by a backhaul node to receive a downlink signal. The adjacent frequency interference signal includes an intermodulation component in the first frequency band. The first frequency band The internal intermodulation component is obtained by the access node after baseband processing, digital and analog processing and power amplification of the received first downlink signal; the receiving unit is also used to obtain the adjacent frequency interference reference signal, the adjacent frequency interference reference The signal includes the intermodulation component in the first frequency band; the processing unit is configured to perform adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal received by the receiving unit to obtain the adjacent frequency interference cancellation signal.

Optionally, the specific method is the same as the corresponding description in the first aspect, which will not be repeated here.

Optionally, the signal processing apparatus may further include a communication interface for transmitting the first downlink signal to the access node.

According to a fourth aspect, an embodiment of the present application further provides a signal processing device, configured to implement the method described in the second aspect above. The signal processing device is an access node or a communication device that supports the access node to implement the method described in the second aspect, for example, the communication device includes a chip system. For example, the signal processing device includes a processing unit and a transmission unit. The processing unit is used to perform baseband processing, digital and analog processing and power amplification on the first downlink signal to obtain a second downlink signal. The second downlink signal includes an intermodulation component in the first frequency band. The frequency band used by the transmitting node to receive the downlink signal; the sending unit is used to send the second downlink signal in the second frequency band, the second frequency band is the frequency band used by the access node to send the downlink signal, the second frequency band and the first frequency band Adjacent; the processing unit is also used to obtain an adjacent frequency interference reference signal based on the second downlink signal, the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band, and the adjacent frequency interference reference signal is the first adjacent frequency interference reference A signal or a second adjacent channel interference reference signal; the sending unit is also used to transmit the adjacent channel interference reference signal to the backhaul node.

Optionally, the specific method is the same as the corresponding description in the second aspect, which will not be repeated here.

Optionally, the signal processing apparatus may further include a communication interface for receiving the first downlink signal transmitted by the backhaul node.

It should be noted that the functional modules of the third aspect and the fourth aspect described above can be implemented by hardware, and can also be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions. For example, a transceiver is used to complete the functions of the receiving unit and the sending unit, a processor is used to complete the functions of the processing unit, and a memory is used by the processor to process program instructions of the method of the embodiments of the present application. The processor, transceiver and memory are connected through the bus and complete the communication with each other. Specifically, reference may be made to the function of the backhaul node or the access behavior in the method described in the first aspect to the method described in the second aspect.

In a fifth aspect, an embodiment of the present application further provides a signal processing apparatus, which is used to implement the method described in the first aspect above. The signal processing device is a backhaul node or a communication device that supports the backhaul node to implement the method described in the first aspect, for example, the communication device includes a chip system. For example, the signal processing device includes a processor for implementing the functions of the method described in the first aspect above. The signal processing device may further include a memory for storing program instructions and data. The memory is coupled to the processor, and the processor may call and execute program instructions stored in the memory to implement the functions in the method described in the first aspect above. The signal processing apparatus may further include a communication interface, and the communication interface is used for the signal processing apparatus to communicate with other devices. Exemplarily, if the signal processing apparatus is a return node, the other device is an access node.

In a possible device, the signal processing device includes: a communication interface, and the communication interface is used for the signal processing device to communicate with other devices. Exemplarily, the communication interface includes an optical fiber and a transceiver. The transceiver is used to receive adjacent frequency interference signals in a first frequency band. The first frequency band is a frequency band used by a return node to receive downlink signals. The adjacent frequency interference signals include intermodulation components in the first frequency band. The intermodulation component is obtained by the access node through baseband processing, digital and analog processing, and power amplification on the received first downlink signal. The backhaul node is used to obtain an adjacent frequency interference reference signal through an optical fiber, and the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band. The memory is used to store program instructions. The processor is configured to perform adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal to obtain the adjacent frequency interference cancellation signal.

In a sixth aspect, an embodiment of the present application further provides a signal processing apparatus, which is used to implement the method described in the second aspect above. The signal processing device is an access node or a communication device that supports the access node to implement the method described in the second aspect. For example, the signal processing device includes a chip system. For example, the signal processing device includes a processor for implementing the functions in the method described in the second aspect above. The communication device may further include a memory for storing program instructions and data. The memory is coupled to the processor, and the processor may call and execute program instructions stored in the memory to implement the functions in the method described in the second aspect above. The signal processing apparatus may further include a communication interface, and the communication interface is used for the signal processing apparatus to communicate with other devices. Exemplarily, if the signal processing apparatus is an access node, the other device is a backhaul node.

In a possible device, the signal processing device includes: a communication interface, and the communication interface is used for the signal processing device to communicate with other devices. Exemplarily, the communication interface includes an optical fiber and a transceiver. The memory is used to store program instructions. The processor is used to perform baseband processing, digital and analog processing and power amplification on the first downlink signal to obtain a second downlink signal. The second downlink signal includes an intermodulation component in the first frequency band, and the first frequency band is a return node The frequency band used for receiving downstream signals. The processor is further used to obtain an adjacent frequency interference reference signal according to the second downlink signal. The adjacent frequency interference reference signal includes an intermodulation component in the first frequency band, and the adjacent frequency interference reference signal is the first adjacent frequency interference reference signal or the second Adjacent frequency interference reference signal. The transceiver is used to send a second downlink signal in a second frequency band. The second frequency band is a frequency band used by the access node to send the downlink signal, and the second frequency band is adjacent to the first frequency band. The access node is used to transmit the adjacent frequency interference reference signal to the backhaul node through the optical fiber.

According to a seventh aspect, an embodiment of the present application further provides a computer-readable storage medium, including: computer software instructions; when the computer software instructions run in the signal processing device, the signal processing device performs the first aspect or the second aspect The method.

According to an eighth aspect, an embodiment of the present application further provides a computer program product containing instructions, which, when the computer program product runs in a signal processing device, causes the signal processing device to execute the method described in the first aspect or the second aspect.

In a ninth aspect, an embodiment of the present application provides a chip system. The chip system includes a processor, and may further include a memory, configured to implement the function of a backhaul node or an access node in the foregoing method. The chip system may be composed of chips, or may contain chips and other discrete devices.

According to a tenth aspect, an embodiment of the present application further provides a communication system including the backhaul node described in the third aspect or a communication device supporting the backhaul node to implement the method described in the first aspect, and the fourth aspect The described access node or communication device supporting the access node to implement the method described in the second aspect;

Or the communication system includes the backhaul node described in the fifth aspect or a communication device supporting the backhaul node to implement the method described in the first aspect, and the access node described in the sixth aspect or the support access node implementing the second aspect Communication device of the described method.

In addition, for the technical effects brought by the design methods in any of the above aspects, please refer to the technical effects brought by the different design methods in the first and second aspects, which will not be repeated here.

In the embodiment of the present application, the names of the backhaul node, the access node, and the signal processing device do not limit the device itself. In actual implementation, these devices may appear under other names. As long as the functions of each device are similar to the embodiments of the present application, they fall within the scope of the claims of the present application and their equivalent technologies.

BRIEF DESCRIPTION

FIG. 1 is an example of adjacent-frequency interference provided by the prior art;

FIG. 2 is a simplified structural example diagram of a communication system provided by an embodiment of the present application;

FIG. 3 is an example diagram of adjacent frequency interference provided by an embodiment of the present application;

4 is a flowchart of a signal processing method provided by an embodiment of the present application;

FIG. 5 is an example diagram of an adjacent channel interference cancellation result provided by an embodiment of the present application; FIG.

6 is a flowchart of another signal processing method provided by an embodiment of the present application;

7 is a diagram illustrating an example of the composition of a signal processing device provided by an embodiment of the present application;

8 is a diagram illustrating an example of the composition of another signal processing device provided by an embodiment of the present application;

9 is a diagram showing an example of the composition of yet another signal processing device provided by an embodiment of the present application;

10 is an exemplary diagram of an adjacent channel interference cancellation structure provided by an embodiment of this application;

FIG. 11 is another exemplary diagram of an adjacent channel interference cancellation structure provided by an embodiment of this application;

FIG. 12 is an exemplary diagram of an enhanced adjacent channel interference cancellation structure provided by an embodiment of the present application.

detailed description

In order to describe the following embodiments clearly and concisely, a brief introduction of related technologies is first given:

Adjacent frequency interference refers to mutual interference between signals of adjacent or similar channels. At present, in order to make full use of the spectrum resources allocated by the system, the frequency interval between channels is usually set to be small. Because the FM signal contains an infinite number of side-frequency components, when some of the side-frequency components in the FM signal fall into the passband of the adjacent channel receiver, this causes adjacent-frequency interference. Adjacent channel interference can also be called adjacent channel interference.

In actual use, adjacent frequency interference mainly refers to signal interference of adjacent frequencies of the used signal frequency, and the performance of the receiving filter is not ideal, so that adjacent signals leak into the transmission bandwidth to cause interference. FIG. 1 is an example of adjacent-channel interference provided by the prior art.

In the embodiment of the present application, since the access transmission band of the access node includes the backhaul reception band of the backhaul node, after the access node sends the access downlink signal including the intermodulation component in the access transmission band, the backhaul The node receives the intermodulation component of the backhaul receiving band in the backhaul receiving band. The intermodulation component of the backhaul receiving band causes interference to the backhaul node when demodulating the backhaul signal, that is, the access link generates the backhaul link Adjacent frequency interference. The adjacent channel interference caused by the access link to the backhaul link may also be called self-interference. However, the adjacent-channel interference generated by the access link on the backhaul link will not be suppressed by the filter, and the adjacent link generated on the backhaul link can be reduced according to the signal processing method provided in the embodiment of the present application. Frequency interference.

The implementation of the embodiments of the present application will be described in detail below with reference to the drawings.

FIG. 2 is a simplified structural example diagram of a communication system provided by an embodiment of the present application. As shown in FIG. 2, the communication system includes: a host node 201, a backhaul node 202, an access node 203, and at least one terminal device (terminal device 204 and terminal device 205 shown in FIG. 2). The host node 201 is connected to the backhaul node 202 in a wireless manner, and the access node 203 is connected to the terminal device in a wireless manner. The backhaul node 202 and the access node 203 may be independent different physical devices, and the backhaul node 202 and the access node 203 may be connected by an optical fiber. Of course, the logical function of the backhaul node 202 and the logical function of the access node 203 can also be integrated on the same physical device, or it can be a physical device that integrates part of the function of the backhaul node 202 and part of the access The function of the node 203. For example, the physical device may be a relay node. The terminal device may be fixed or mobile. FIG. 2 is only a schematic diagram, and the communication system may also include other network devices, such as core network devices, which are not shown in FIG. 2. The embodiments of the present application do not limit the number of core network devices, host nodes, backhaul nodes, access nodes, and terminal devices included in the communication system.

The host node 201 may be an entity on the network side for transmitting or receiving signals, such as a new generation base station (generation Node B, gNodeB). The host node 201 may be a network device for communicating with mobile devices. The network device can be an access point (AP) in a wireless local area network (WLAN), a global system for mobile (GSM), or code division multiple access (code division multiple access). Base station (BTS) in CDMA) can also be base station (NodeB, NB) in wideband code division multiple access (WCDMA) or long term evolution (LTE) ) In the evolutionary base station (evolutional Node B, eNB or eNodeB), or relay station or access point, or vehicle equipment, wearable devices and future 5G network network equipment or future evolution of public land mobile network (public land mobile network (PLMN) network equipment in the network, or gNodeB in the NR system, etc. In addition, in the embodiments of the present application, the network device provides services for the cell, and the terminal device communicates with the network device through the transmission resources (eg, frequency domain resources, or spectrum resources) used by the cell, and the cell may be a network device (For example, a base station) The corresponding cell, the cell may belong to a macro base station, or a base station corresponding to a small cell (small cell), where the small cell may include: a metro cell, a micro cell, and a pico cell (pico cell), femto cell (femto cell), etc. These small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services. In addition, in other possible situations, the host node may be another device that provides a wireless communication function for the terminal device. The embodiments of the present application do not limit the specific technology and specific device form adopted by the host node. For convenience of description, in the embodiments of the present application, an apparatus that provides a wireless communication function for a terminal device is called a network device.

The terminal equipment (user equipment, UE) may be a wireless terminal equipment capable of receiving scheduling and instruction information of the network equipment. The wireless terminal equipment may be a device that provides voice and / or data connectivity to the user, or a handheld device with a wireless connection function , Or other processing equipment connected to the wireless modem. The wireless terminal device can communicate with one or more core networks or the Internet via a wireless access network (eg, radio access network, RAN), and the wireless terminal device can be a mobile terminal device, such as a mobile phone (or "cellular" phone) , Mobile (phone), computer and data card, for example, may be portable, pocket-sized, handheld, computer built-in or vehicle-mounted mobile devices, which exchange language and / or data with the wireless access network. For example, personal communications (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (wireless local loop (WLL) stations, personal digital assistants (personal digital assistants, PDAs), tablets) Computers (pad), computers with wireless transceiver functions and other equipment. The wireless terminal equipment may also be called a system, a subscriber unit, a subscriber station, a mobile station, a mobile station (MS), a remote station, and an access point ( access (AP), remote terminal (remote terminal), access terminal (access terminal), user terminal (user terminal), user agent (user agent), user station (subscriber station, SS), user terminal device (customer presets, equipment, CPE), terminal, user equipment (UE), mobile terminal (MT), etc. The wireless terminal device may also be a wearable device and a next-generation communication system, for example, a terminal device in a 5G network or a terminal device in a public land mobile network (PLMN) network that evolves in the future, and an Terminal equipment, etc.

The backhaul node 202 is used to receive the backhaul downlink signal sent by the host node 201 and send the backhaul uplink signal to the host node 201. The link between the host node 201 and the backhaul node 202 may be referred to as a backhaul link. The frequency band used for data transmission between the host node 201 and the backhaul node 202 may be referred to as a backhaul band. For example, the frequency band used by the backhaul node 202 to receive the downlink signal sent by the host node 201 may be referred to as a backhaul reception band. The frequency band used by the backhaul node 202 to send the upstream signal to the host node 201 may be referred to as the backhaul transmission band. The backhaul receiving band and the backhaul transmitting band are located at different positions in the frequency spectrum. The bandwidth of the backhaul receiving band and the bandwidth of the backhaul transmitting band may be the same or different.

The access node 203 is used to send an access downlink signal to the terminal device and receive an access uplink signal sent by the terminal device. The link between the terminal device and the access node 203 may be referred to as an access link. The frequency band used for data transmission between the terminal device and the access node 203 may be referred to as an access band. For example, the frequency band used by the access node 203 to send downlink signals to the terminal device may be referred to as an access transmission band. The frequency band used by the access node 203 to receive the uplink signal sent by the terminal device may be referred to as an access receiving band. The access transmission band and the access reception band are located at different positions in the frequency spectrum. The bandwidth of the access transmission band and the bandwidth of the access reception band may be the same or different.

In the embodiment of the present application, the access transmission band includes a backhaul reception band. Understandably, the backhaul receiving band partially overlaps with the access sending band, and the bandwidth of the access sending band is larger than the bandwidth of the backhaul receiving band. The remaining frequency band of the access transmitting band except the backhaul receiving band is adjacent to the backhaul receiving band. The host node may pre-configure the bandwidth of the backhaul receiving band and the backhaul receiving band for the backhaul node. The host node may pre-configure the access transmission band and the bandwidth of the access transmission band for the access node. The host node also needs to configure the backhaul time slot and the access time slot in advance for the backhaul node and the access node. For convenience of description, in the following, it is assumed that the backhaul receiving band is the first frequency band, and the remaining frequency band excluding the backhaul receiving band from the access transmit band is the second frequency band, and the first frequency band and the second frequency band constitute a third frequency band, that is, the third frequency band For access to the launch band. As shown in FIG. 3, in the backhaul time slot, the backhaul node can receive the backhaul downlink signal sent by the host node in the first frequency band, and the access node can send the access downlink signal to the terminal device in the second frequency band. The access downlink signal includes the intermodulation component in the first frequency band. Understandably, due to the nonlinear characteristics of the power amplifier (PA), the intermodulation component in the first frequency band is generated after the return downlink signal is processed by the baseband processing module of the access node and the power amplifier. The intermodulation component in the first frequency band, which is the extended part of the return downlink signal, is a non-linear component. When the access node sends the access downlink signal to the terminal device in the second frequency band, the return node can receive the intermodulation component in the first frequency band after spatial transmission, that is, the return node receives the adjacent frequency interference signal, resulting in adjacent frequency interference The signal causes interference when the backhaul node demodulates the received backhaul downlink signal. In the access time slot, no data transmission is performed between the backhaul node and the host node in the first frequency band, that is, the host node does not send a backhaul downlink signal to the backhaul node. In order to improve the utilization rate of the spectrum, the access node may send an access downlink signal to the terminal device in the third frequency band. In this case, although the access downlink signal sent by the access node includes the intermodulation component in the first frequency band, there is no data transmission between the backhaul node and the host node in the first frequency band, so the first frequency band The intermodulation component in the internal frequency does not cause adjacent frequency interference, and the intermodulation component in the first frequency band can be ignored.

In order to solve the problem of how to reduce the adjacent frequency interference caused by the access link to the backhaul link without changing the device structure, the embodiments of the present application provide a signal processing method, the basic principle of which is: access node After receiving the backhaul downlink signal, perform baseband processing, digital and analog processing and power amplification on the backhaul downlink signal to obtain an access downlink signal including the intermodulation component in the first frequency band, and send the access downlink signal to the terminal device , And acquiring the adjacent frequency interference reference signal according to the access downlink signal, and transmitting the adjacent frequency interference reference signal to the backhaul node. The adjacent frequency interference reference signal includes intermodulation components in the first frequency band. After the backhaul node receives the adjacent frequency interference signal in the first frequency band and obtains the adjacent frequency interference reference signal, it performs adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal to obtain the adjacent frequency interference cancellation signal . The signal processing method provided in the embodiments of the present application implements the use of a reference channel to obtain an adjacent frequency interference reference signal without changing the device structure, and performs adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal. Therefore, the adjacent-channel interference generated by the access link to the backhaul link is effectively reduced.

Network equipment and terminal equipment can be deployed on land, including indoor or outdoor, handheld or vehicle-mounted; it can also be deployed on the water; it can also be deployed on aircraft, balloons and satellites in the air. The embodiments of the present application do not limit the application scenarios of the host node, the backhaul node, the access node, and the terminal device.

The communication between the host node, the backhaul node, the access node and the terminal device and between the terminal device and the terminal device can be through licensed spectrum (licensed spectrum) or unlicensed spectrum (unlicensed spectrum). Communicate through licensed and unlicensed spectrum. The embodiments of the present application do not limit the spectrum resources used between the host node, the backhaul node, the access node, and the terminal device.

The embodiments of the present application can be applied to downlink signal transmission, and can also be applied to device-to-device (device to device, D2D) signal transmission. For D2D signal transmission, the sending device is a terminal device, and the corresponding receiving device is also a terminal device.

The terms "first", "second", and "third" in the specification, claims, and drawings of this application are used to distinguish different objects, not to limit a specific order.

In the embodiments of the present application, words such as "exemplary" or "for example" are used as examples, illustrations or explanations. Any embodiments or design solutions described as “exemplary” or “for example” in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific manner.

The following uses the backhaul node and the access node shown in FIG. 2 as examples to describe the signal processing method provided in the embodiments of the present application in detail. 4 is a flowchart of a signal processing method provided by an embodiment of the present application. As shown in FIG. 4, the method may include:

S401. The access node performs baseband processing, digital and analog processing, and power amplification on the first downlink signal to obtain a second downlink signal.

After the access node receives the first downlink signal transmitted by the backhaul node, the baseband processing module included in the access node performs baseband processing on the first downlink signal, and then performs digital and analog processing on the baseband processed signal. For example, digital pre-distortion (DPD) correction and digital-to-analog conversion. For specific processing methods of baseband processing and digital and analog processing, reference may be made to the prior art, and the embodiments of the present application will not repeat them here. Devices that perform digital and analog processing on the signals processed by the baseband may include a DPD module and a digital-to-analog conversion module.

After performing baseband processing and digital and analog processing on the first downlink signal, the power amplifier included in the access node performs power amplification on the signal after baseband processing and digital and analog processing to obtain a second downlink signal. Due to the nonlinear characteristics of the power amplifier, the baseband processed and digital and analog processed signals are processed by the power amplifier of the access node to generate an intermodulation component, which includes the intermodulation component in the first frequency band and the first frequency band External intermodulation components. The intermodulation component, which is the expanded part of the power amplified signal after baseband processing and digital and analog processing, is a non-linear component. The second downlink signal includes intermodulation components in the first frequency band and intermodulation components outside the first frequency band. The first frequency band is the frequency band used by the backhaul node to receive the downlink signal.

It should be noted that the access node may receive the first downlink signal transmitted by the backhaul node through the optical fiber. The first downlink signal received by the access node is an optical signal. The access node first needs to convert the first downlink signal in the form of an optical signal into a first downlink signal in the form of a digital signal, and the first downlink signal in the form of a digital signal. After the signal is processed by the baseband processing module, the first downlink signal in the form of a digital signal after baseband processing is obtained, and the first downlink signal in the form of a digital signal after baseband processing is subjected to digital and analog processing to obtain the first downlink in analog form signal.

S402. The access node sends a second downlink signal in the second frequency band.

The access node sends a second downlink signal to the terminal device in the second frequency band. The second frequency band is the frequency band used by the access node to send the downlink signal in the return time slot. The second frequency band is adjacent to the first frequency band. The first frequency band is the frequency band used by the backhaul node to receive the downlink signal in the backhaul time slot. The second frequency band and the first frequency band constitute a third frequency band, and the third frequency band is a frequency band used by an access node to transmit downlink in an access slot.

S403. The backhaul node receives the adjacent channel interference signal in the first frequency band.

Since the second frequency band is adjacent to the first frequency band, the second downlink signal sent by the access node to the terminal device in the second frequency band includes the intermodulation component in the first frequency band, causing the backhaul node to receive the The intermodulation component in the first frequency band of spatial transmission, that is, the backhaul node receives the adjacent frequency interference signal. The adjacent frequency interference signal includes intermodulation components in the first frequency band.

S404. The access node obtains the adjacent channel interference reference signal according to the second downlink signal.

In the first possible implementation manner, the access node may first perform analog-to-digital conversion on the second downlink signal to obtain a first adjacent frequency interference reference signal, and transmit the first adjacent frequency interference reference signal to the return node. The interference reference signal includes intermodulation components in the first frequency band and intermodulation components outside the first frequency band. For example, the analog-to-digital converter in the feedback channel for DPD correction included in the access node may be multiplexed to perform analog-to-digital conversion on the second downlink signal to obtain the first adjacent-channel interference reference signal. Optionally, the reference channel may further include at least one of an analog filter, a mixer, and an amplifier. The access node may perform analog processing and analog-to-digital conversion on the second downlink signal to obtain the first adjacent-frequency interference reference signal. The analog processing includes at least one of filtering, mixing and amplification. The analog filter, mixer, and amplifier may also be analog filters, mixers, and amplifiers in the feedback channel included in the multiplexing access node for DPD correction.

In the second achievable manner, the access node may first perform analog-to-digital conversion on the second downlink signal to obtain the first adjacent-channel interference reference signal, and then obtain the second from the first adjacent-channel interference reference signal according to the first frequency band The adjacent frequency interference reference signal transmits a second adjacent frequency interference reference signal to the backhaul node, and the second adjacent frequency interference reference signal includes intermodulation components in the first frequency band. For example, the analog-to-digital converter in the feedback channel for DPD correction included in the access node may be multiplexed to perform analog-to-digital conversion on the second downlink signal and use a digital filter to interfere with the reference signal from the first adjacent frequency according to the first frequency band To obtain the second adjacent channel interference reference signal. Optionally, the reference channel may further include at least one of an analog filter, a mixer, and an amplifier. The access node may perform analog processing, analog-to-digital conversion, and filtering on the second downlink signal to obtain a second adjacent-frequency interference reference signal. The analog processing includes at least one of filtering, mixing and amplification.

Optionally, before filtering the first adjacent-channel interference reference signal according to the first frequency band to obtain the second adjacent-channel interference reference signal, other digital processing such as frequency shifting and sampling rate change may be performed on the first adjacent-channel interference reference signal. The change of the sampling rate may also be performed after filtering the first adjacent frequency interference reference signal according to the first frequency band to obtain the second adjacent frequency interference reference signal, which is not limited in the embodiment of the present application.

Optionally, when the access node obtains the adjacent frequency interference reference signal according to the second downlink signal, other analog-to-digital converters, analog filters, mixers, amplifiers, and digital signals included in the access node outside the feedback channel may also be used Devices such as filters are not limited in the embodiments of the present application.

It should be noted that when the access node obtains the adjacent channel interference reference signal according to the second downlink signal, the second downlink signal used may be the second part of the energy in the second downlink signal output by the access node from the power amplifier through the coupler Downlink signal.

S405. The access node transmits the adjacent channel interference reference signal to the backhaul node.

S406. The backhaul node receives the adjacent channel interference reference signal transmitted by the access node.

The backhaul node may receive the adjacent frequency interference reference signal transmitted by the access node through the optical fiber, and the adjacent frequency interference reference signal includes the intermodulation component in the first frequency band.

In the first possible implementation manner, the adjacent channel interference reference signal is the first adjacent channel interference reference signal, the return node receives the first adjacent channel interference reference signal transmitted by the access node, and the first adjacent channel interference reference signal is the access After the node performs analog-to-digital conversion on the second downlink signal, the first adjacent-frequency interference reference signal further includes intermodulation components outside the first frequency band. Further, the backhaul node can also obtain the second adjacent frequency interference reference signal from the first adjacent frequency interference reference signal according to the first frequency band, and filter out the intermodulation components outside the first frequency band, thereby improving The performance of adjacent frequency interference cancellation processing.

In the second achievable manner, the adjacent channel interference reference signal is a second adjacent channel interference reference signal, the return node receives the second adjacent channel interference reference signal transmitted by the access node, and the second adjacent channel interference reference signal is the access The node performs analog-to-digital conversion and filtering on the second downlink signal.

It should be noted that the sequence of the steps of the signal processing method provided in the embodiments of the present application can be adjusted appropriately, and the steps can also be increased or decreased according to the situation. For example, if the order between S402 and S403 and S404 and S406 is interchangeable, that is, the access node may first obtain the adjacent channel interference reference signal according to the second downlink signal, and transmit the adjacent channel interference reference signal to the backhaul node, Then send the second downlink signal in the second frequency band; the backhaul node may first receive the adjacent frequency interference reference signal transmitted by the access node, and then receive the adjacent frequency interference signal in the first frequency band. Anyone who is familiar with the technical field in the technical scope disclosed in this application can easily think of a changing method, which should be covered within the protection scope of this application, so no further description will be given.

S407. The backhaul node performs adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal to obtain the adjacent frequency interference cancellation signal.

The adjacent-channel interference signal and the adjacent-channel interference reference signal received by the backhaul node are a type of data stream, and performing adjacent-channel interference cancellation on the adjacent-channel interference signal according to the adjacent-channel interference reference signal can be regarded as a cyclic iteration process . It is assumed that the i-th adjacent-channel interference cancellation process is any one of the adjacent-channel interference cancellation processes on the adjacent-channel interference reference signal.

In the i-th iteration, the return node obtains the i-th adjacent channel interference image signal according to the i-th adjacent channel interference reference signal and the i-th coefficient, and then logically subtracts the i-th adjacent channel interference signal according to the i-th adjacent channel interference image signal After operation, the i-th adjacent channel interference cancellation signal is obtained. Wherein, performing a logical subtraction operation on the i-th adjacent channel interference signal according to the i-th adjacent channel interference image signal can be understood as the i-th adjacent channel interference signal minus the i-th adjacent channel interference mirror signal to obtain the i-th adjacent channel interference cancellation signal. The i-th coefficient is determined by the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference cancellation signal. Understandably, after the i-th adjacent channel interference cancellation signal is obtained, the i + 1-th coefficient is determined using the i-th adjacent channel interference cancellation signal and the i-th adjacent channel interference reference signal. In the i + 1 iteration, the return node obtains the i + 1 adjacent channel interference image signal according to the i + 1 adjacent channel interference reference signal and the i + 1 coefficient, and then according to the i + 1 adjacent channel interference image signal Perform a logic subtraction operation on the i + 1 adjacent frequency interference signal to obtain the i + 1 adjacent frequency interference cancellation signal. Among them, i is an integer, i takes values from 2 to N, N is an integer, and N is infinity.

Exemplarily, when i = 2, in the second iteration, the return node obtains the second adjacent channel interference image signal according to the second adjacent channel interference reference signal and the second coefficient, and then according to the second adjacent channel interference image signal Perform a logic subtraction operation on the second adjacent-channel interference signal to obtain the second adjacent-channel interference cancellation signal. Among them, the second coefficient is determined by the first adjacent channel interference reference signal and the first adjacent channel interference cancellation signal. When i = 3, in the third iteration, the return node obtains the third adjacent channel interference image signal according to the third adjacent channel interference reference signal and the third coefficient, and then performs the third adjacent channel interference image signal on the third adjacent channel interference signal The frequency interference signal performs a logic subtraction operation to obtain the signal after the third adjacent frequency interference cancellation. Among them, the third coefficient is determined by the second adjacent channel interference reference signal and the second adjacent channel interference cancellation signal.

It should be noted that, in the first iteration, the return node obtains the first adjacent channel interference image signal according to the first adjacent channel interference reference signal and the initial value of the coefficient, and then performs the first adjacent channel interference image signal based on the first adjacent channel interference image signal. The interference signal performs a logic subtraction operation to obtain the first adjacent-frequency interference cancellation signal. The initial value of the coefficient can be 0.

In addition, when determining the i-th coefficient based on the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference cancellation signal, the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference can be determined After canceling the signal, an optimization algorithm is used to determine the i-th coefficient. The optimization algorithm may be a least mean square (LMS) algorithm, a recursive least square (RLS) algorithm, or a least square (LS) algorithm.

Exemplarily, as shown in FIG. 5, an embodiment of the present application provides an example of a result of cancellation of adjacent-channel interference. The second downlink signal shown in (a) of FIG. 5 includes the main signal and the intermodulation component in the first frequency band. The second downlink signal shown in (b) of FIG. 5 includes the main signal and the intermodulation component in the first frequency band. However, compared to (a) of FIG. 5, the second signal in the adjacent frequency band shown in (b) of FIG. 5 The intermodulation component in a frequency band is weakened. The main signal is a service signal included in the second downlink signal.

The signal processing method provided by the embodiment of the present application realizes the adjacent frequency interference cancellation processing on the adjacent frequency interference signal through the adjacent frequency interference reference signal without changing the device structure, effectively reducing the access link pair Adjacent frequency interference generated by the backhaul link.

Further, before the access node performs baseband processing, digital and analog processing and power amplification on the first downlink signal to obtain the second downlink signal, that is, before S401, as shown in FIG. 6, the embodiment of the present application may further include the following steps .

S601. The backhaul node transmits the first downlink signal to the access node.

After receiving the backhaul downlink signal from the host node in the first frequency band, the backhaul node demodulates the backhaul downlink signal to obtain service information, and then re-encodes the service information to obtain the first downlink signal, and converts the first downlink signal Transmission to the access node. The backhaul node may transmit the first downlink signal to the access node through the optical fiber.

S602. The access node receives the first downlink signal transmitted by the backhaul node.

The access node may receive the first downlink signal transmitted by the return node through the optical fiber.

In the above embodiments provided by the present application, the methods provided by the embodiments of the present application are introduced from the perspective of the backhaul node, the access node, and the interaction between the backhaul node and the access node. It can be understood that, for each network element, such as a backhaul node and an access node, to implement the functions in the method provided in the embodiments of the present application, the backhaul node and the access node include corresponding hardware structures to perform each function and / or Or software module. Those skilled in the art should easily realize that, in combination with the algorithm steps of the examples described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed by hardware or computer software driven hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

The embodiments of the present application may divide the functional modules of the backhaul node and the access node according to the above method example, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module in. The above integrated modules may be implemented in the form of hardware or software function modules. It should be noted that the division of the modules in the embodiments of the present application is schematic, and is only a division of logical functions. In actual implementation, there may be another division manner.

In the case where each functional module is divided corresponding to each function, FIG. 7 shows a schematic diagram of a possible composition of the signal processing apparatus mentioned above and in the embodiment. The signal processing apparatus can perform any of the method embodiments of the present application. Steps performed by the backhaul node in a method embodiment. As shown in FIG. 7, the communication device is a backhaul node or a communication device that supports the backhaul node to implement the method provided in the embodiment. For example, the communication device may be a chip system. The signal processing apparatus may include a receiving unit 701 and a processing unit 702.

The receiving unit 701 is used to support the signal processing device to execute the method described in the embodiments of the present application. For example, the receiving unit 701 is used to execute or support the signal processing device to execute S403 and S406 in the signal processing method shown in FIG. 4 and S403 and S406 in the signal processing method shown in FIG. 6.

The processing unit 702 is configured to execute or support the signal processing device to execute S407 in the signal processing method shown in FIG. 4 and S407 in the signal processing method shown in FIG. 6.

In the embodiment of the present application, further, as shown in FIG. 7, the signal processing apparatus may further include: a sending unit 703.

The sending unit 703 is used to send data, for example, to support the signal processing device to execute S601 in the method shown in FIG. 6.

It should be noted that all relevant content of the steps involved in the above method embodiments can be referred to the function description of the corresponding function module, which will not be repeated here.

The signal processing device provided by the embodiment of the present application is used to execute the method of any of the above embodiments, and therefore can achieve the same effect as the method of the above embodiment.

In the case where each functional module is divided corresponding to each function, FIG. 8 shows a schematic diagram of a possible composition of the signal processing apparatus mentioned above and in the embodiment. The signal processing apparatus can perform any of the method embodiments of the present application. Steps performed by the access node in a method embodiment. As shown in FIG. 8, the signal processing device is an access node or a communication device that supports the access node to implement the method provided in the embodiment. For example, the communication device may be a chip system. The signal processing apparatus may include: a processing unit 801 and a sending unit 802.

The processing unit 801 is used to support the signal processing device to execute the method described in the embodiments of the present application. For example, the processing unit 801 is used to execute or to support the signal processing device to execute S401 and S404 in the signal processing method shown in FIG. 4 and S401 and S404 in the signal processing method shown in FIG. 6.

The sending unit 802 is configured to execute or support the signal processing device to execute S402 and S405 in the signal processing method shown in FIG. 4 and S402 and S405 in the signal processing method shown in FIG. 6.

In the embodiment of the present application, further, as shown in FIG. 8, the signal processing apparatus may further include: a receiving unit 803.

The receiving unit 803 is used to receive data, for example, to support the signal processing device to execute S602 in the method shown in FIG. 6.

As shown in FIG. 9, a signal processing device 900 provided by an embodiment of the present application is used to implement the function of a backhaul node in the foregoing method. The signal processing device 900 may be a backhaul node or a device in the backhaul node. The signal processing device 900 may be a chip system. In the embodiment of the present application, the chip system may be composed of a chip, or may include a chip and other discrete devices. Alternatively, the signal processing device 900 is used to implement the function of the access node in the above method. The signal processing device 900 may be an access node or a device in the access node. The signal processing device 900 may be a chip system. In the embodiment of the present application, the chip system may be composed of a chip, or may include a chip and other discrete devices.

The signal processing device 900 includes at least one processor 901, configured to implement the function of a backhaul node or an access node in the method provided by the embodiments of the present application. Exemplarily, the processor 901 may be used to perform baseband processing, digital and analog processing, and power amplification on the first downlink signal to obtain a second downlink signal, obtain an adjacent frequency interference reference signal according to the second downlink signal, and according to the adjacent frequency The interference reference signal performs adjacent frequency interference cancellation processing on the adjacent frequency interference signal, etc. For details, refer to the detailed description in the method example, and details are not described here.

The signal processing device 900 may further include at least one memory 902 for storing program instructions and / or data. The memory 902 and the processor 901 are coupled. The coupling in the embodiments of the present application is an indirect coupling or communication connection between devices, units or modules, which may be in electrical, mechanical or other forms, and is used for information interaction between devices, units or modules. The processor 901 may cooperate with the memory 902. The processor 901 may execute program instructions stored in the memory 902. At least one of the at least one memory may be included in the processor.

The signal processing apparatus 900 may further include a communication interface 903 for communicating with other devices through a transmission medium, so that the apparatus used in the signal processing apparatus 900 can communicate with other devices. Exemplarily, if the signal processing device is a return node, the other device is an access node. If the signal processing device is an access node, the other device is a return node. The processor 901 uses the communication interface 903 to send and receive data, and is used to implement the method performed by the backhaul node or the access node described in the embodiments corresponding to FIG. 4 and FIG. 6.

In this embodiment of the present application, the specific connection medium between the communication interface 903, the processor 901, and the memory 902 is not limited. In this embodiment of the present application, the communication interface 903, the processor 901, and the memory 902 are connected by a bus 904 in FIG. 9, and the bus is indicated by a thick line in FIG. 9. The connection between other components is only for schematic illustration. , Not to limit. The bus can be divided into an address bus, a data bus, and a control bus. For ease of representation, only a thick line is used in FIG. 9, but it does not mean that there is only one bus or one type of bus.

In the embodiments of the present application, the processor may be a general-purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, which may be implemented or Perform the disclosed methods, steps, and logical block diagrams in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in conjunction with the embodiments of the present application may be directly embodied and executed by a hardware processor, or may be executed and completed by a combination of hardware and software modules in the processor.

In the embodiment of the present application, the memory may be a non-volatile memory, such as a hard disk (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), for example Random access memory (random-access memory, RAM). The memory is any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present application may also be a circuit or any other device capable of realizing a storage function, which is used to store program instructions and / or data.

It should be noted that if the signal processing device is an access node or a device in the access node, the signal processing device may use a coupler and an analog-to-digital converter included in the signal processing device to obtain the adjacent frequency interference reference signal according to the second downlink signal . The coupler is used to couple the second downlink signal with partial energy from the second downlink signal output from the power amplifier, and the analog-to-digital converter is used to analog-to-digital convert the second downlink signal to obtain the first adjacent-frequency interference reference signal. The signal processing device may further include a digital filter for acquiring the second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band.

Exemplarily, FIG. 10 provides an example diagram of an adjacent channel interference cancellation structure according to an embodiment of the present application. The access node includes a baseband processing module 1001, a digital / analog processing module 1002, a power amplifier 1003, a coupler 1004, an analog filter 1005, a mixer 1006, a low noise amplifier 1007, an analog-to-digital converter 1008, and a digital filter 1009. As shown in FIG. 10, the reference channel includes a coupler 1004, an analog filter 1005, a mixer 1006, a low noise amplifier 1007, an analog-to-digital converter 1008, and a digital filter 1009. The reference channel is used to obtain the adjacent channel interference reference signal according to the second downlink signal. Among them, the coupler 1004, the analog filter 1005, the mixer 1006, the low noise amplifier 1007, and the analog-to-digital converter 1008 may be devices in the feedback channel used for DPD correction in the access node, or may be included in the access node Devices outside the feedback channel for DPD correction. The transmission channel includes a digital / analog processing module 1002 and a power amplifier 1003. The return node includes a finite-length impulse response (FIR) filter 1010 and a solution module 1011. FIR filters can also be called non-recursive filters.

It should be noted that, in actual applications, the access node and the backhaul node may also include other processing modules, which will not be repeated in the embodiments of the present application.

The baseband processing module 1001 is used to perform baseband processing on the first downlink signal. The digital / analog processing module 1002 is used to perform digital processing on the baseband-processed signal and convert digital first analog signals into analog digital first analog signals. The power amplifier 1003 is used to perform power amplification on the first downlink signal in analog form to obtain the second downlink signal. The access node sends a second downlink signal to the terminal device through the access antenna in the second frequency band. At the same time, the second downlink signal output from the power amplifier 1003 by the coupler couples part of the energy of the second downlink signal into the reference channel. The analog filter 1005, mixer 1006, low noise amplifier 1007, and analog-to-digital converter 1008 are used to The second downlink signal is sequentially filtered, mixed, amplified and analog-to-digital converted to obtain a first adjacent frequency interference reference signal. The digital filter 1009 is used to obtain a second adjacent frequency interference signal from the first adjacent frequency interference reference signal according to the first frequency band Frequency interference reference signal.

The backhaul node and the access node can be connected by optical fiber. The access node transmits the second adjacent frequency interference reference signal to the backhaul node through the optical fiber. The backhaul node receives the adjacent frequency interference signal through the backhaul antenna. The FIR filter 1010 and the solution module 1011 perform adjacent-channel interference cancellation processing on the adjacent-channel interference signal according to the second adjacent-channel interference reference signal to obtain the adjacent-channel interference cancellation signal. The FIR filter 1010 is used to obtain the adjacent-channel interference image signal according to the second adjacent-channel interference reference signal and coefficients. The cancellation point performs a logic subtraction operation on the adjacent frequency interference signal according to the adjacent frequency interference image signal to obtain the adjacent frequency interference cancellation signal. The solution module 1011 is used for acquiring coefficients of the second adjacent-channel interference reference signal and the adjacent-channel interference cancellation signal.

Exemplarily, in the i-th iteration, the FIR filter 1010 is used to obtain the i-th adjacent-channel interference image signal according to the i-th adjacent-channel interference reference signal and the i-th coefficient, and the cancellation point is based on the i-th adjacent-channel interference image signal. The i-adjacent-channel interference signal performs a logic subtraction operation to obtain the i-adjacent-channel interference cancellation signal. The i-th coefficient is determined by the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference cancellation signal. Understandably, after the i-th adjacent channel interference cancellation signal is obtained, the i + 1-th coefficient is determined using the i-th adjacent channel interference cancellation signal and the i-th adjacent channel interference reference signal. The solving module 1011 is configured to determine the i + 1 coefficient using the i-th adjacent channel interference cancellation signal and the i-th adjacent channel interference reference signal. In the i + 1th iteration, the FIR filter 1010 is used to obtain the i + 1 adjacent channel interference image signal according to the i + 1 adjacent channel interference reference signal and the i + 1th coefficient, and the cancellation point is based on the i + 1 The adjacent channel interference image signal performs a logical subtraction operation on the i + 1 adjacent channel interference signal to obtain the i + 1 adjacent channel interference cancellation signal. The solving module 1011 is used to determine the i + 2 coefficient by using the i + 1 adjacent channel interference cancellation signal and the i + 1 adjacent channel interference reference signal. Among them, i is an integer, i takes values from 2 to N, N is an integer, and N is infinity.

In another implementable manner, a digital filter included in the backhaul node may also be used to filter out the intermodulation components outside the first frequency band in the first adjacent-channel interference reference signal. Exemplarily, as shown in FIG. 11, an embodiment of the present application provides another example diagram of an adjacent channel interference cancellation structure. The access node includes a baseband processing module 1101, a digital / analog processing module 1102, a power amplifier 1103, a coupler 1104, an analog filter 1105, a mixer 1106, a low noise amplifier 1107, and an analog-to-digital converter 1108. The reference channel includes an analog filter 1105, a mixer 1106, a low noise amplifier 1107, and an analog-to-digital converter 1108. As shown in FIG. 11, the reference channel includes a coupler 1104, an analog filter 1105, a mixer 1106, a low noise amplifier 1107, and an analog-to-digital converter 1108. The reference channel is used to obtain the adjacent channel interference reference signal according to the second downlink signal. Among them, the coupler 1104, the analog filter 1105, the mixer 1106, the low noise amplifier 1107 and the analog-to-digital converter 1108 may be devices in the feedback channel used for DPD correction in the access node, or may include the access node Devices outside the feedback channel for DPD correction. The transmission channel includes a digital / analog processing module 1102 and a power amplifier 1103. The return node includes a digital filter 1109, a FIR filter 1110, and a solving module 1111.

The baseband processing module 1101 is used to perform baseband processing on the first downlink signal. The digital / analog processing module 1102 is used to perform digital processing on the baseband-processed signal and convert digital first analog signals into analog digital first analog signals. The power amplifier 1103 is used to perform power amplification on the first downlink signal in analog form to obtain a second downlink signal. The access node sends a second downlink signal to the terminal device through the access antenna in the second frequency band. At the same time, the second downlink signal output from the power amplifier 1103 by the coupler couples part of the energy of the second downlink signal into the reference channel, and the analog filter 1105, mixer 1106, low noise amplifier 1107, and analog-to-digital converter 1108 are used to The second downlink signal is sequentially filtered, mixed, amplified, and analog-to-digital converted to obtain a first adjacent-frequency interference reference signal.

The backhaul node and the access node can be connected by optical fiber. The access node transmits the first adjacent frequency interference reference signal to the backhaul node through the optical fiber. The backhaul node receives the adjacent frequency interference signal through the backhaul antenna. The digital filter 1109 is used to obtain a second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band. The FIR filter 1110 and the solving module 1111 perform adjacent-channel interference cancellation processing on the adjacent-channel interference signal according to the second adjacent-channel interference reference signal to obtain the adjacent-channel interference cancellation signal. The FIR filter 1110 is used to obtain the adjacent-channel interference image signal according to the second adjacent-channel interference reference signal and coefficients. The cancellation point performs a logic subtraction operation on the adjacent frequency interference signal according to the adjacent frequency interference image signal to obtain the adjacent frequency interference cancellation signal. The solution module 1111 is used for acquiring coefficients of the second adjacent-channel interference reference signal and the adjacent-channel interference cancellation signal.

In addition, in order to increase the signal-to-noise ratio of the adjacent channel interference reference signal and improve the adjacent channel interference cancellation performance, before the access node obtains the adjacent channel interference reference signal according to the second downlink signal, it can suppress the main signal. The so-called main signal is a service signal included in the second downlink signal, that is, a carrier signal carrying service information. Exemplarily, the main signal suppression filter is used to suppress the main signal included in the adjacent frequency interference reference signal according to the second frequency band. As shown in FIG. 12, an embodiment of the present application provides an example of an enhanced adjacent channel interference cancellation structure. The access node includes a baseband processing module 1201, a digital / analog processing module 1202, a power amplifier 1203, a coupler 1204, an analog filter 1205, a mixer 1206, a low noise amplifier 1207, an analog-to-digital converter 1208, a digital filter 1209 and Main signal suppression module 1212. The return node includes a FIR filter 1210 and a solving module 1211. The main signal suppression module 1212 is used to suppress the main signal included in the adjacent frequency interference reference signal. For functions of other devices shown in FIG. 12, reference may be made to the description of the corresponding devices shown in FIG. 10, and the embodiments of the present application are not described herein again. Of course, the adjacent signal interference cancellation structure shown in FIG. 11 may also include a main signal suppression module to suppress the main signal included in the adjacent signal interference reference signal. For the specific location of the main signal suppression module, reference may be made to the position of the main signal suppression module shown in FIG. 12, and details are not described herein in this embodiment of the present application.

The access node involved in the embodiments of the present application may be the access nodes shown in FIGS. 10-12. The backhaul nodes involved in the embodiments of the present application may be the backhaul nodes shown in FIGS. 10-12.

Through the description of the above embodiments, those skilled in the art can clearly understand that, for convenience and conciseness of description, only the above-mentioned division of each functional module is used as an example for illustration. In practical applications, the above-mentioned functions can be allocated as needed It is completed by different functional modules, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed device and method may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules or units is only a division of logical functions. In actual implementation, there may be other divisions, for example, multiple units or components may be The combination can either be integrated into another device, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may be one physical unit or multiple physical units, that is, may be located in one place, or may be distributed in multiple different places . Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or software functional unit.

The methods provided in the embodiments of the present application may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, all or part of the processes or functions according to the embodiments of the present invention are generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, a network device, a terminal, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be from a website site, computer, server or data center Transmission to another website, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device including a server, a data center, and the like integrated with one or more available media. The usable medium may be a magnetic medium (eg, floppy disk, hard disk, magnetic tape), optical medium (eg, digital video disc (DVD)), or semiconductor medium (eg, SSD), or the like.

The above is only the specific implementation of this application, but the scope of protection of this application is not limited to this, any changes or replacements within the technical scope disclosed in this application should be covered within the scope of protection of this application . Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A signal processing method, which includes:

Receiving an adjacent-channel interference signal in a first frequency band, the first frequency band is a frequency band used by a backhaul node to receive a downlink signal, the adjacent-frequency interference signal includes an intermodulation component in the first frequency band, the first The intermodulation component in the frequency band is obtained by the access node after baseband processing, digital and analog processing and power amplification of the received first downlink signal;

Acquiring an adjacent frequency interference reference signal, where the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band;

Performing adjacent-channel interference cancellation processing on the adjacent-channel interference signal according to the adjacent-channel interference reference signal to obtain the adjacent-channel interference cancellation signal.
The signal processing method according to claim 1, wherein the adjacent frequency interference reference signal is a first adjacent frequency interference reference signal, and the acquiring the adjacent frequency interference reference signal includes:

Receiving a first adjacent frequency interference reference signal transmitted by the access node, the first adjacent frequency interference reference signal is a signal after the access node performs analog-to-digital conversion on a second downlink signal, and the first adjacent frequency The interference reference signal further includes an intermodulation component outside the first frequency band, and the second downlink signal is the base node processing, digital and analog processing, and power amplification of the received first downlink signal by the access node After getting.
The signal processing method according to claim 2, wherein after the receiving the first adjacent channel interference reference signal transmitted by the access node, the method further comprises:

Acquiring a second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band.
The signal processing method according to claim 1, wherein the adjacent frequency interference reference signal is a second adjacent frequency interference reference signal, and the acquiring the adjacent frequency interference reference signal includes:

Receiving a second adjacent channel interference reference signal transmitted by the access node, where the second adjacent channel interference reference signal is a signal after the access node performs analog-to-digital conversion and filtering on a second downlink signal, the second The downlink signal is obtained by the access node after performing baseband processing, digital and analog processing, and power amplification on the received first downlink signal.
The signal processing method according to any one of claims 1 to 4, wherein the adjacent frequency interference signal is subjected to adjacent frequency interference cancellation processing according to the adjacent frequency interference reference signal to obtain adjacent frequency interference Post-cancellation signals, including:

Obtaining the i-th adjacent channel interference image signal according to the i-th adjacent channel interference reference signal and the i-th coefficient, the i-th coefficient is obtained by canceling the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference The signal is determined, where i is an integer, the value of i is 2 to N, N is an integer, the signal after the first adjacent frequency interference cancellation is adjacent to the first adjacent frequency interference signal by the first adjacent frequency interference image signal The interference cancellation process determines that the first adjacent-channel interference image signal is determined by the first adjacent-channel interference reference signal and the initial value of the coefficient;

Performing adjacent-channel interference cancellation processing on the i-th adjacent-channel interference signal according to the i-th adjacent-channel interference image signal to obtain the i-th adjacent-channel interference cancellation signal.
The signal processing method according to any one of claims 1 to 5, wherein before the receiving the adjacent frequency interference signal in the first frequency band, the method further comprises:

Transmitting the first downlink signal to the access node.
A signal processing method, which includes:

Perform baseband processing, digital and analog processing, and power amplification on the first downlink signal to obtain a second downlink signal, where the second downlink signal includes an intermodulation component in a first frequency band, which is received by a backhaul node The frequency band used by the downstream signal;

Sending the second downlink signal in a second frequency band, the second frequency band is a frequency band used by an access node to send a downlink signal, and the second frequency band is adjacent to the first frequency band;

Acquiring an adjacent frequency interference reference signal according to the second downlink signal, the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band, and the adjacent frequency interference reference signal is the first adjacent frequency interference reference signal or the first Two adjacent frequency interference reference signal;

Transmitting the adjacent channel interference reference signal to the backhaul node.
The signal processing method according to claim 7, wherein the adjacent frequency interference reference signal is a first adjacent frequency interference reference signal, and the obtaining the adjacent frequency interference reference signal according to the second downlink signal includes:

Performing analog-to-digital conversion on the second downlink signal to obtain the first adjacent-frequency interference reference signal, and the first adjacent-frequency interference reference signal further includes an intermodulation component outside the first frequency band.
The signal processing method according to claim 7, wherein the adjacent frequency interference reference signal is a second adjacent frequency interference reference signal, and the obtaining the adjacent frequency interference reference signal according to the second downlink signal includes:

Performing analog-to-digital conversion on the second downlink signal to obtain a first adjacent frequency interference reference signal, where the first adjacent frequency interference reference signal further includes intermodulation components outside the first frequency band;

Acquiring a second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band.
The signal processing method according to any one of claims 7-9, characterized in that before the first downlink signal is subjected to baseband processing, digital and analog processing, and power amplification to obtain a second downlink signal, The method also includes:

Receiving the first downlink signal transmitted by the backhaul node.
The signal processing method according to any one of claims 7-10, characterized in that, before acquiring the adjacent frequency interference reference signal according to the second downlink signal, the method further comprises:

Suppressing the main signal included in the adjacent-channel interference reference signal, where the main signal is a service signal included in the second downlink signal.
A signal processing device, characterized in that it includes:

The receiving unit is configured to receive an adjacent channel interference signal in a first frequency band, where the first frequency band is a frequency band used by a backhaul node to receive a downlink signal, and the adjacent frequency interference signal includes an intermodulation component in the first frequency band The intermodulation component in the first frequency band is obtained by the access node after performing baseband processing, digital and analog processing, and power amplification on the received first downlink signal;

The receiving unit is further used to obtain an adjacent frequency interference reference signal, where the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band;

The processing unit is configured to perform adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal received by the receiving unit to obtain a signal after adjacent frequency interference cancellation.
The signal processing device according to claim 12, wherein the adjacent channel interference reference signal is a first adjacent channel interference reference signal, and the receiving unit is configured to:

Receiving a first adjacent frequency interference reference signal transmitted by the access node, the first adjacent frequency interference reference signal is a signal after the access node performs analog-to-digital conversion on a second downlink signal, and the first adjacent frequency The interference reference signal further includes an intermodulation component outside the first frequency band, and the second downlink signal is the base node processing, digital and analog processing, and power amplification of the received first downlink signal by the access node After getting.
The signal processing device according to claim 13, wherein the processing unit is further configured to:

Acquiring a second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band.
The signal processing device according to claim 12, wherein the adjacent channel interference reference signal is a second adjacent channel interference reference signal, and the receiving unit is configured to:

Receiving a second adjacent channel interference reference signal transmitted by the access node, where the second adjacent channel interference reference signal is a signal after the access node performs analog-to-digital conversion and filtering on a second downlink signal, the second The downlink signal is obtained by the access node after performing baseband processing, digital and analog processing, and power amplification on the received first downlink signal.
The signal processing device according to any one of claims 12 to 15, wherein the processing unit is configured to:

Obtaining the i-th adjacent channel interference image signal according to the i-th adjacent channel interference reference signal and the i-th coefficient, the i-th coefficient is obtained by canceling the i-1 adjacent channel interference reference signal and the i-1 adjacent channel interference The signal is determined, where i is an integer, the value of i is 2 to N, N is an integer, the signal after the first adjacent frequency interference cancellation is adjacent to the first adjacent frequency interference signal by the first adjacent frequency interference image signal The interference cancellation process determines that the first adjacent-channel interference image signal is determined by the first adjacent-channel interference reference signal and the initial value of the coefficient;

Performing adjacent-channel interference cancellation processing on the i-th adjacent-channel interference signal according to the i-th adjacent-channel interference image signal to obtain the i-th adjacent-channel interference cancellation signal.
The signal processing device according to any one of claims 12 to 16, wherein the device further comprises:

The sending unit is configured to transmit the first downlink signal to the access node.
A signal processing device, characterized in that it includes:

The processing unit is configured to perform baseband processing, digital and analog processing and power amplification on the first downlink signal to obtain a second downlink signal, the second downlink signal includes an intermodulation component in a first frequency band, and the first frequency band The frequency band used by the backhaul node to receive downlink signals;

A sending unit, configured to send the second downlink signal obtained by the processing unit in a second frequency band, the second frequency band is a frequency band used by an access node to send a downlink signal, and the second frequency band and the first One frequency band is adjacent;

The processing unit is further configured to obtain an adjacent frequency interference reference signal according to the second downlink signal, the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band, and the adjacent frequency interference reference signal is the first A neighboring channel interference reference signal or a second neighboring channel interference reference signal;

The sending unit is also used to transmit the adjacent frequency interference reference signal obtained by the processing unit to a backhaul node.
The signal processing apparatus according to claim 18, wherein the adjacent channel interference reference signal is a first adjacent channel interference reference signal, and the processing unit is configured to:

Performing analog-to-digital conversion on the second downlink signal to obtain the first adjacent-frequency interference reference signal, and the first adjacent-frequency interference reference signal further includes an intermodulation component outside the first frequency band.
The signal processing device according to claim 18, wherein the adjacent channel interference reference signal is a second adjacent channel interference reference signal, and the processing unit is configured to:

Performing analog-to-digital conversion on the second downlink signal to obtain a first adjacent frequency interference reference signal, where the first adjacent frequency interference reference signal further includes intermodulation components outside the first frequency band;

Acquiring a second adjacent-channel interference reference signal from the first adjacent-channel interference reference signal according to the first frequency band.
The signal processing device according to any one of claims 18-20, wherein the device further comprises:

The receiving unit is configured to receive the first downlink signal transmitted by the backhaul node.
The signal processing device according to any one of claims 18 to 21, wherein the processing unit is further configured to:

Suppressing the main signal included in the adjacent-channel interference reference signal, where the main signal is a service signal included in the second downlink signal.
A signal processing device, comprising: at least one processor, a memory, a bus, and a transceiver, wherein the memory is used to store a computer program so that the computer program is implemented when executed by the at least one processor The signal processing method according to any one of claims 1-6, the transceiver is used to receive an adjacent channel interference signal in a first frequency band, the first frequency band is a frequency band used by a backhaul node to receive a downlink signal, The adjacent-frequency interference signal includes an intermodulation component in the first frequency band. The intermodulation component in the first frequency band is the baseband processing, digital and analog processing, and power amplification of the first downlink signal received by the access node After getting.
A signal processing device, comprising: at least one processor, a memory, a bus, a transceiver, and a reference channel, wherein the memory is used to store a computer program so that the computer program is used by the at least one processor When executed, the signal processing method according to any one of claims 7 to 11 is implemented, and the reference channel is used to obtain a neighboring channel interference reference signal according to a second downlink signal, the neighboring channel interference reference signal including the first frequency band Intermodulation component, the adjacent frequency interference reference signal is the first adjacent frequency interference reference signal or the second adjacent frequency interference reference signal, and the first frequency band is the frequency band used by the backhaul node to receive the downlink signal.
The signal processing device according to claim 24, wherein the reference channel includes a coupler and an analog-to-digital converter, the coupler is used to couple a second downlink signal, and the analog-to-digital converter is used to The signal undergoes analog-to-digital conversion to obtain the first adjacent-frequency interference reference signal.
The signal processing device according to claim 25, characterized in that the signal processing device further comprises a digital filter for acquiring from the first adjacent frequency interference reference signal according to the first frequency band The second adjacent channel interferes with the reference signal.
A computer-readable storage medium, characterized by comprising: computer software instructions;

When the computer software instruction runs in a signal processing device or a chip built in the signal processing device, causes the signal processing device to execute the signal processing method according to any one of claims 1-6 or according to claim 7 The signal processing method according to any one of -11.
A computer program product containing instructions, characterized in that, when the computer program product runs in a signal processing device or a chip built in the signal processing device, the signal processing device is caused to perform any of claims 1 to 6. The signal processing method according to one item or the signal processing method according to any one of claims 7 to 11.
A communication system, including: a host node, a return node, an access node, and at least one terminal device; wherein, the return node and the access node are connected through an optical fiber;

The backhaul node is configured to process the received backhaul downlink signal sent by the host node to obtain a first downlink signal, and transmit the first downlink signal to the interface through the optical fiber Access node

The access node is configured to perform baseband processing, digital and analog processing and power amplification on the first downlink signal to obtain a second downlink signal, and the second downlink signal includes an intermodulation component in the first frequency band, The first frequency band is a frequency band used by the backhaul node to receive downlink signals;

The access node is further configured to send the second downlink signal in a second frequency band, the second frequency band is a frequency band used by the access node to send the downlink signal, the second frequency band and the first frequency band Adjacent

The access node is further configured to obtain an adjacent frequency interference reference signal according to the second downlink signal, where the adjacent frequency interference reference signal includes an intermodulation component in the first frequency band;

The access node is also used to transmit the adjacent frequency interference reference signal to the backhaul node through the optical fiber;

The backhaul node is also used to receive adjacent frequency interference signals in the first frequency band, the adjacent frequency interference signals include intermodulation components in the first frequency band, and intermodulation components in the first frequency band Obtained by the access node after performing baseband processing, digital and analog processing, and power amplification on the received first downlink signal;

The backhaul node is also used to obtain the adjacent frequency interference reference signal through the optical fiber;

The backhaul node is further configured to perform adjacent frequency interference cancellation processing on the adjacent frequency interference signal according to the adjacent frequency interference reference signal to obtain a signal after adjacent frequency interference cancellation.