CN120050144A

CN120050144A - Channel correction method, device, electronic equipment and readable storage medium

Info

Publication number: CN120050144A
Application number: CN202311606325.XA
Authority: CN
Inventors: 张璞; 王大飞; 颜祥玉
Original assignee: Ruijie Networks Co Ltd
Current assignee: Ruijie Networks Co Ltd
Priority date: 2023-11-27
Filing date: 2023-11-27
Publication date: 2025-05-27

Abstract

The embodiment of the application provides a channel correction method, a channel correction device, electronic equipment and a readable storage medium, and belongs to the technical field of communication. The channel correction method comprises the steps of performing time delay adjustment on a first radio frequency signal of a first channel of a remote radio frequency unit RRU according to a first time delay adjustment value to obtain a second radio frequency signal, and performing filtering processing on the second radio frequency signal through a correction filter to obtain a third radio frequency signal, wherein the first time delay adjustment value and the correction filter are determined based on a frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used for correcting amplitude errors and phase errors of the first channel.

Description

Channel correction method, device, electronic equipment and readable storage medium

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a channel correction method, a channel correction device, electronic equipment and a readable storage medium.

Background

Time-division Duplex (TDD) is one of full-Duplex communication technologies used in a mobile communication system. For a TDD system, one main advantage is that the uplink and downlink air interface channels can be considered as reciprocal, so that the channel response of the corresponding downlink channel can be obtained through the Sounding reference signal (Sounding REFERENCE SIGNAL, SRS), and the non-codebook precoding is further performed on the downlink PDSCH (Physical Downlink SHARED CHANNEL, PDSCH), so that the performance of the downlink PDSCH is greatly improved.

However, in actual products, the channel response obtained by the baseband is affected by a plurality of factors such as hardware, and the baseband is also affected by hardware or external interference besides the air interface channel, so that certain deviation occurs in amplitude phase of each antenna. In addition, since the antenna transmission and reception are not the same circuit, the amplitude and phase errors of the transmission and reception are different for each antenna. In this case, when precoding is performed by SRS, the precoding gain cannot be obtained, resulting in poor transmission performance.

Disclosure of Invention

The embodiment of the application provides a channel correction method, a device, electronic equipment and a medium, which are used for solving the problem that when precoding is carried out through SRS, the precoding gain cannot be obtained, and the transmission performance is poor.

In order to achieve the above purpose, the embodiment of the application adopts the following technical scheme:

According to a first aspect of the embodiment of the application, a channel correction method is provided, which comprises the steps of performing time delay adjustment on a first radio frequency signal of a first channel of a remote radio unit RRU according to a first time delay adjustment value to obtain a second radio frequency signal, and performing filtering processing on the second radio frequency signal through a correction filter to obtain a second radio frequency signal, wherein the first time delay adjustment value and the correction filter are determined based on a frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used for correcting amplitude and phase errors of the first channel.

According to the channel correction method provided by the embodiment of the application, the correction filter and the first delay adjustment value are determined based on the frequency domain correction coefficient of the first channel of the RRU, the signal delay is adjusted through the first delay adjustment value, and then the time delay adjusted signal is subjected to filtering processing in a time domain filtering convolution mode, so that the amplitude phase and the time delay of the time domain adjusted signal based on the frequency domain correction coefficient are realized, the problem that the existing time domain correction scheme only depends on the time delay adjustment granularity supported by hardware is avoided, and the transmission performance of the channel is further improved.

In combination with the first aspect, in one possible implementation manner, before performing delay adjustment on the first radio frequency signal of the first channel of the RRU according to the first delay adjustment value, the channel correction method provided by the embodiment of the application further includes obtaining a frequency domain correction coefficient of the first channel of the RRU, performing inverse fast fourier transform IFFT processing on the frequency domain correction coefficient to obtain a corresponding time domain sampling sequence, where the time domain sampling sequence includes X sampling points, X is a positive integer, and determining, based on a first sampling point of the X sampling points, the first delay adjustment value and the correction filter, where the first sampling point is a sampling point with a maximum corresponding amplitude of the X sampling points.

With reference to the first aspect and the foregoing possible implementation manners, in another possible implementation manner, the determining the first delay adjustment value based on a first sampling point of the X sampling points includes determining the first delay adjustment value according to a preset filter length and an index of the first sampling point in the time domain sampling sequence, where the preset filter length is a preset filter length of the correction filter.

With reference to the first aspect and the foregoing possible implementation manners, in another possible implementation manner, the determining the correction filter based on a first sampling point of the X sampling points includes determining a first filter coefficient according to a first L sampling points and a last M sampling points of the first sampling point, and generating the correction filter based on the first filter coefficient, where L is a positive integer less than or equal to X/2, and M is a positive integer less than or equal to X/2.

With reference to the first aspect and the foregoing possible implementation manners, in another possible implementation manner, the frequency domain correction coefficient includes at least one sample point, before performing IFFT processing on the frequency domain correction coefficient, the method further includes copying and flipping first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, copying and flipping last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, where N is a positive integer, splicing the first sample point sequence, the second sample point sequence and the at least one sample point to obtain a spliced frequency domain correction coefficient, and performing IFFT processing on the frequency domain correction coefficient, including performing IFFT processing on the spliced frequency domain correction coefficient.

With reference to the first aspect and the foregoing possible implementation manners, in another possible implementation manner, the splicing the first sample point sequence, the second sample point sequence and the at least one sample point to obtain a spliced frequency domain correction coefficient includes splicing the first sample point sequence to a starting position of the at least one sample point, and splicing the second sample point sequence to an ending position of the at least one sample point to obtain a spliced frequency domain correction coefficient.

With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, the filtering processing, by using a correction filter, the second radio frequency signal to obtain a third radio frequency signal includes inputting the second radio frequency signal to the correction filter to perform time domain convolution processing, and outputting the third radio frequency signal.

The second aspect of the embodiment of the application provides a channel correction device, which comprises a processing module, wherein the processing module is used for carrying out time delay adjustment on a first radio frequency signal of a first channel of a remote radio frequency unit RRU according to a first time delay adjustment value to obtain a second radio frequency signal, and is also used for carrying out filtering processing on the second radio frequency signal through a correction filter to obtain a third radio frequency signal, wherein the first time delay adjustment value and the correction filter are determined based on a frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used for correcting amplitude and phase errors of the first channel.

According to the channel correction device provided by the embodiment of the application, the channel correction device determines the correction filter of each channel and the first delay adjustment value of each channel based on the frequency domain correction coefficient of each channel of the RRU, and adjusts the delay and amplitude phase error of each channel based on the correction filter of each channel and the first delay adjustment value of each channel, so that the phase and amplitude of a frequency domain signal can be continuously adjusted in a time domain filtering convolution manner, the problem that the existing time domain correction scheme only depends on the delay adjustment granularity supported by hardware is avoided, and the transmission performance of the channel is further improved.

With reference to the second aspect, in a possible implementation manner, the device further includes an acquisition module, the acquisition module is configured to acquire a frequency domain correction coefficient of a first channel of the RRU before performing delay adjustment on a first radio frequency signal of the first channel of the RRU according to a first delay adjustment value, the processing module is further configured to perform inverse fast fourier transform IFFT processing on the frequency domain correction coefficient acquired by the acquisition module to obtain a corresponding time domain sampling sequence, where the time domain sampling sequence includes X sampling points, and X is a positive integer, and the processing module is further configured to determine, based on a first sampling point of the X sampling points, the first delay adjustment value and the correction filter, where the first sampling point is a sampling point with a maximum corresponding amplitude.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processing module is specifically configured to determine the first delay adjustment value according to a preset filter length and an index of the first sampling point in the time domain sampling sequence, where the preset filter length is a preset filter length of the correction filter.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processing module is specifically configured to determine a first filter coefficient according to a first L sample points and a last M sample points of the first sample point, and generate the correction filter based on the first filter coefficient, where L is a positive integer less than or equal to X/2, and M is a positive integer less than or equal to X/2.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the frequency domain correction coefficient includes at least one sample point;

The processing module is further configured to copy and flip the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, copy and flip the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, where N is a positive integer, and splice the first sample point sequence, the second sample point sequence and the at least one sample point to obtain a spliced frequency domain correction coefficient, and the processing module is specifically configured to perform IFFT processing on the spliced frequency domain correction coefficient.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processing module is specifically configured to splice the first sample point sequence to a start position of the at least one sample point, and splice the second sample point sequence to an end position of the at least one sample point, so as to obtain a spliced frequency domain correction coefficient.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processing module is specifically configured to input the second radio frequency signal into the correction filter to perform a time domain convolution process, and output the third radio frequency signal.

A third aspect of embodiments of the present application provides an electronic device comprising a processor and a memory storing a program or instructions executable on the processor, which when executed by the processor, implement the steps of the channel correction method as described in the first aspect and possible implementations of the first aspect thereof.

In a fourth aspect of embodiments of the present application, there is provided a readable storage medium having stored thereon a program or instructions which, when executed by a processor, implement the steps of the channel correction method as described in the first aspect and possible implementations of the first aspect thereof.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained according to these drawings without inventive faculty for a person skilled in the art.

FIG. 1 is a schematic flow chart of a channel correction method according to an embodiment of the present application;

fig. 2 is a schematic diagram of an IFFT-derived time-domain sample sequence according to an embodiment of the present application;

FIG. 3 is a schematic diagram of extending a frequency domain correction coefficient according to an embodiment of the present application;

fig. 4A is a simulation diagram of a path loss value of a signal of an RRU channel according to an embodiment of the present application;

fig. 4B is a simulation diagram of error vector magnitude of signals of an RRU channel according to an embodiment of the present application;

Fig. 5 is a schematic structural diagram of a channel calibration device according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged, as appropriate, such that embodiments of the present application may be implemented in sequences other than those illustrated or described herein, and that the objects identified by "first," "second," etc. are generally of a type, and are not limited to the number of objects, such as the first object may be one or more.

In addition, the term "and/or" is merely an association relation describing the association object, and means that three kinds of relations may exist, for example, a and/or B, and that three kinds of cases where a exists alone, while a and B exist alone, exist alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

The terms "at least one," "at least one," and the like in the description and in the claims, mean that they encompass any one, any two, or a combination of two or more of the objects. For example, at least one of a, b, c (item) may represent "a", "b", "c", "a and b", "a and c", "b and c" and "a, b and c", wherein a, b, c may be single or plural. Similarly, the term "at least two" means two or more, and the meaning of the expression is similar to the term "at least one".

Some concepts and/or terms involved in the channel correction method provided in the embodiment of the present application are explained below.

1. Multiple-in Multiple-Out-put system (MIMO)

MIMO is also called as a multiple input multiple output system, and refers to a structure in which multiple antennas are simultaneously used at a transmitting end and a receiving end, and this technology can increase the capacity and spectrum utilization rate of a communication system by multiple without increasing the bandwidth, which is a key technology that must be adopted by a new generation of mobile communication systems. .

2. Channel

The channel refers to an RRU channel or an antenna channel of an antenna connected with the RRU, the RRU channel comprises a single channel and multiple channels, the port of the RRU is connected with one antenna in total, and the multiple channels are connected with multiple antennas. The channels may be divided into a reception channel and a transmission channel according to the type of signal transmission/reception of the channels.

3. Sounding reference signal (Sounding REFERENCE SIGNAL, SRS)

The SRS is used for estimating the frequency domain information of the uplink channel, performing frequency selective scheduling, estimating the uplink channel and performing downlink beam shaping.

The channel correction method provided by the embodiment of the application is described in detail below through specific embodiments and application scenes thereof with reference to the accompanying drawings.

For a TDD (Time-division Duplex) system, one major advantage is that the air interface channels of the uplink and downlink can be considered reciprocal, i.eTherefore, the corresponding channel response of the downlink channel can be obtained through SRS (Sounding REFERENCE SIGNAL, SRS), the precoding of the non-codebook is further carried out on the downlink PDSCH (Physical Downlink SHARED CHANNEL, PDSCH), and the performance of the downlink PDSCH is greatly improved.

However, in actual products, the channel response obtained by the baseband is affected by a plurality of factors such as hardware, and the amplitude phase of each antenna is also affected by hardware (or interference) in addition to the channel of the air interface, so that a certain deviation (cause) occurs in the amplitude phase of each antenna. In addition, because the antenna receiving and transmitting are not the same circuit, the amplitude-phase errors sent and received by each antenna are different, namely the channel response obtained by the baseband is as follows:

Wherein, For the air interface channel, E ^RX,E^TX is the amplitude-phase deviation caused by each antenna, so that H ^UL≠(H^DL)^T exists, when precoding is performed through SRS, the precoding gain is not obtained, antenna correction is needed, and the antenna correction coefficient is calculated so that:

Meanwhile, in many situations, for example, a situation that the antennas need to be combined at radio frequency, each channel can only be corrected in the time domain, and at this time, how to correct the time offset and the frequency selection characteristics of each channel becomes a problem.

The conventional technical scheme is that channel correction is performed by a linear fitting method, and the conventional channel correction method by the linear fitting method can only adjust integer times of time delay or adjust the adjustment granularity supported by hardware when adjusting group time delay, and the adjustment effect is limited due to the limitation of the adjustment granularity, and the related technology ignores the frequency selection characteristic of the channel, so that the performance is reduced.

According to the channel correction method provided by the embodiment of the application, the correction filter and the first time delay adjustment value are determined based on the frequency domain correction coefficient of the first channel of the RRU, the time delay of the signal is adjusted through the first time delay adjustment value, the phase and the amplitude of the frequency domain signal are continuously adjusted in a time domain filtering convolution mode for the time delay adjusted signal, the time delay and amplitude/phase adjustment effect is achieved, the problem that the existing time domain correction scheme only depends on the time delay adjustment granularity supported by hardware is avoided, and compared with the existing scheme, the frequency selection characteristic of the device is corrected through the correction filter, so that the correction effect is improved, and the transmission performance of the channel is further improved.

Fig. 1 is a flowchart of a channel correction method according to an embodiment of the present application, as shown in fig. 1, the channel correction method may include the following steps S201 and S202:

In step S201, the channel calibration device performs delay adjustment on a first radio frequency signal of a first channel of the remote radio unit RRU according to the first delay adjustment value, so as to obtain a second radio frequency signal.

The first delay adjustment value is determined based on a frequency domain correction coefficient of a first channel of the RRU.

Alternatively, in the embodiment of the present application, the channel correction device may transform the frequency domain correction coefficient into the time domain through IFFT, and determine the first delay adjustment value based on the amplitude peak of the sampling point of the time domain.

Optionally, in the embodiment of the present application, the first channel may be a signal transmission channel of an RRU of the first cell, or the first channel may be a signal receiving channel of an RRU of the first cell.

Alternatively, in an embodiment of the present application, the first channel may include a plurality of channels.

For example, two RRUs exist in the cell 1, the two RRUs perform DMIMO networking, the two RRUs are RRU1 and RRU2 respectively, two antenna channels exist in RRU1 and RRU2, each antenna channel is used for receiving or transmitting a radio frequency signal, and then the first channel may include two antenna channels of RRU1 and two antenna channels of RRU 2.

Alternatively, in an embodiment of the present application, the first radio frequency signal may be a radio frequency signal sent through a first channel.

Optionally, in an embodiment of the present application, the second radio frequency signal may be a radio frequency signal with a time delay smaller than a threshold value obtained by performing time delay adjustment on the first radio frequency signal.

Step S202, the channel correction device performs filtering processing on the second radio frequency signal through the correction filter to obtain a third radio frequency signal.

The correction filter is determined based on a frequency domain correction coefficient of a first channel of the RRU.

Alternatively, in the embodiment of the present application, the channel correction device may transform the above-mentioned frequency domain correction coefficient into the time domain through IFFT, and calculate the filter coefficient based on the amplitude/phase characteristics of the sampling points of the time domain, thereby obtaining the correction filter.

Optionally, in an embodiment of the present application, the correction filter is configured to correct an amplitude error and a phase error of the first channel.

Optionally, in an embodiment of the present application, the channel correction device inputs the second radio frequency signal to a correction filter to perform time domain convolution processing, and outputs a third radio frequency signal.

Illustratively, after the radio frequency signal is input to the correction filter, the coefficient of the correction filter is subjected to a time domain convolution operation (i.e. multiply-accumulate) with the radio frequency signal, and the processed radio frequency signal is output. In this way, the amplitude and the phase of the signal can be adjusted by means of time-domain filtering convolution, so that the radio frequency signal with the amplitude/phase characteristics meeting the requirements is obtained.

Taking the first delay adjustment value as τ and taking the correction filter as f as an example, firstly performing integral multiple delay adjustment of τ points on a signal to be corrected of the RRU channel to obtain an adjusted signal x ', and then correcting the adjusted signal x' by using a calculated filter, where the expression is as follows:

wherein x is the signal to be corrected, For the corrected signal, τ is an integer multiple of the delay adjustment, f is a correction filter, and as such, it represents a convolution operation.

It should be noted that in a multi-channel RRU, frequency response inconsistencies due to phase and gain differences, aging, distortion of amplitude/phase characteristics, etc. of a series of devices will all cause time-varying errors of the channels. Thus, the real channel and the ideal channel have larger difference, and the overall performance of the system is affected. Therefore, the channel correction function needs to be realized, and the embodiment of the application realizes tracking and compensating the channel time delay and the amplitude/phase characteristics thereof through the channel correction, so that the amplitude/phase characteristics of the channel and the reference channel tend to be consistent, the error of the channel is reduced, and the precision requirement of a system is met.

According to the channel correction method provided by the embodiment of the application, the channel correction device determines the correction filter of each channel and the first delay adjustment value of each channel based on the frequency domain correction coefficient of each channel of the RRU, and adjusts the delay and amplitude phase error of each channel based on the correction filter of each channel and the first delay adjustment value of each channel, so that the phase and amplitude of a frequency domain signal can be continuously adjusted in a time domain filtering convolution manner, the problem that the existing time domain correction scheme only depends on the delay adjustment granularity supported by hardware is avoided, and the transmission performance of the channel is further improved.

Optionally, in the embodiment of the present application, before the step S201, the channel correction method provided in the embodiment of the present application further includes the following steps S203 to S205:

Step S203, the channel correction device obtains the frequency domain correction coefficient of the first channel of the RRU.

Step S204, the channel correction device carries out Inverse Fast Fourier Transform (IFFT) processing on the frequency domain correction coefficient to obtain a corresponding time domain sampling sequence.

The time domain sampling sequence comprises X sampling points, wherein X is a positive integer.

In step S205, the channel correction device determines a first delay adjustment value and a correction filter based on a first sampling point of the X sampling points.

The first sampling point is the sampling point with the largest corresponding amplitude among the X sampling points.

Alternatively, in the embodiment of the present application, the channel correction device may acquire the frequency domain correction coefficient by transmitting the frequency domain correction sequence based on the LS algorithm or the Argos algorithm.

For example, assume that there are two RRUs, denoted RRU1 and RRU2, each having two antenna channels, networking DMIMO. The frequency domain correction coefficient is calculated by RRUA transmitting a pilot signal, performing channel estimation after receiving the pilot signal by the RRUB to obtain channel response of a channel from RRUA to the RRUB, performing channel estimation after transmitting the pilot signal by the RRUB and performing channel estimation after receiving the pilot signal by the RRUA to obtain channel response of a channel from the RRUB to RRUA, and then calculating a correction value of an antenna of RRUA (namely, a frequency domain correction coefficient) and a correction value of an antenna of the RRUB according to the channel response of the channel from RRUA to the RRUB and the channel response of the channel from the RRUB to RRUA.

It should be noted that, the specific process of acquiring the frequency domain correction coefficient by transmitting the frequency domain correction sequence may be referred to the description of the related art, which is not repeated in the embodiment of the present application.

Optionally, in the embodiment of the present application, the channel correction device performs IFFT processing on the frequency domain correction coefficient to obtain a time domain correction sequence corresponding to the frequency domain correction coefficient. The expression for IFFT processing the frequency domain correction coefficients is as follows:

Where I is the result after IFFT, N _IFFT denotes the number of points of IFFT, and μ is the frequency domain correction coefficient.

Optionally, in an embodiment of the present application, the X sampling points correspond to X magnitudes.

Illustratively, after the frequency domain correction coefficient is subjected to IFFT, an N-point complex number is obtained, and a modulus value of the point complex number is an amplitude characteristic of the original signal at the delay value.

In the IFFT processing, the input signal is a frequency domain correction coefficient, and the output is a correction coefficient for each delay value.

Optionally, in the embodiment of the present application, the channel correction device may search for an amplitude peak value of X sampling points, determine a sampling point (i.e., a first sampling point) with a largest amplitude value of the X sampling points, and obtain a subscript (i.e., an index) of the sampling point in a time domain sampling sequence.

It will be appreciated that a subscript or index of a sample point in a time domain sample sequence may characterize the position of the sample point throughout the sequence.

Alternatively, in the embodiment of the present application, the channel correction device may calculate the filter coefficient based on the amplitude and phase information of the first sampling point to obtain the correction filter.

Alternatively, in the embodiment of the present application, the channel correction device may calculate the first delay adjustment value based on the index of the first sampling point.

Optionally, in the embodiment of the present application, the determining the first delay adjustment value in the step S204 based on the first sampling point of the X sampling points may include the following step S204a:

in step S204a, the channel correction device determines the first delay adjustment value according to the preset filter length and the index of the first sampling point in the time domain sampling sequence.

The preset filter length is the filter length of a preset correction filter.

Alternatively, in the embodiment of the present application, the preset filter length may be an empirical value, where the preset filter length is related to the correction performance and the acceptable complexity, and may be obtained through simulation.

The preset filter length may be 10, for example.

Alternatively, in the embodiment of the present application, the first delay adjustment value may be an integer.

Optionally, in the embodiment of the present application, after obtaining the time domain correction sequence, the channel correction device searches a sampling point with the largest amplitude value among X sampling points of the time domain correction sequence, and calculates the first delay adjustment value according to an index of the sampling point and a preset filter length.

Illustratively, after obtaining the time-domain sample sequence I, a peak value of I is searched, where a subscript corresponding to a largest peak is IDX. Further, in the case where the IDX is less than one half of the number of points of the IFFT, a difference between the IDX and one half of the preset filter length is taken as the first delay adjustment value, or in the case where the IDX is greater than one half of the number of points of the IFFT, a difference between the IDX, the number of points of the IFFT and one half of the preset filter length is taken as the first delay adjustment value, the calculation formula is as follows:

Where N _IFFT is the number of points of the IFFT, N _fliterLen is the filter length, and τ is the first delay adjustment value.

Optionally, in an embodiment of the present application, the determining the correction filter in the step S204 based on the first sampling point of the X sampling points may include the following step S204b:

in step S204b, the channel correction device determines a first filter coefficient according to the first L sample points and the last M sample points of the first sample point, and generates the correction filter based on the first filter coefficient.

Wherein L is a positive integer less than or equal to X/2, and M is a positive integer less than or equal to X/2.

Optionally, in an embodiment of the present application, the number of the L sample points and the number of the M sample points are determined according to a preset filter length. Optionally, L and M are less than or equal to a preset filter length.

Illustratively, if the preset filter length N _fliterLen is 10, the L sample points and the M sample points include 10 sample points in total. For example, L sample points and M sample points may include 5 sample points, respectively, or L sample points may include 7 sample points, M sample points may include 3 sample points, or L sample points may include 3 sample points, and M sample points may include 7 sample points.

It should be noted that the number of L sample points and the number of M sample points listed in the foregoing embodiment are only one possible example, and the number of sample points may be specifically set according to actual requirements, which is not limited by the embodiment of the present application.

Fig. 2 is a schematic diagram of a time domain sampling sequence after IFFT according to an embodiment of the present application, where the horizontal axis of fig. 2 represents indexes of sampling points, fig. 2 shows 150 sampling points, the corresponding index range is 0-150, and the vertical axis represents magnitudes corresponding to the sampling points. As shown in fig. 2, the first L sample points may be the first 4 sample points of the first sample point, the M sample points may be the last 5 sample points of the first sample point, or the first L sample points may be the first 5 sample points of the first sample point, and the M sample points may be the last 4 sample points of the first sample point.

It should be noted that, the sampling points in the solid line box in fig. 2 are the first L sampling points and the last M sampling points selected.

Illustratively, after obtaining the time-domain sampling sequence I, taking the data of the sum of the left and right peaks N _fliterLen as the filter coefficient of the correction filter according to the searched amplitude peak value, and calculating the following formula:

Wherein I is the IFFT result, IDX is the subscript corresponding to the maximum peak of I, N _fliterLen is the filter length, f is the correction filter, The representation is rounded down and up,Representing an upward rounding.

Optionally, in the embodiment of the present application, the frequency domain correction coefficient includes at least one sample point, and before the step S204, the method for channel correction provided in the embodiment of the present application further includes the following step S206 and step S207:

Step S206, the channel correction device copies and turns over the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, and copies and turns over the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence.

Wherein N is a positive integer.

Step S207, the channel correction device splices the first sample point sequence, the second sample point sequence and at least one sample point to obtain a spliced frequency domain correction coefficient.

In combination of the above step S206 and step S207, the process of IFFT processing the frequency domain correction coefficients in the above step S204 may include the following step S204a:

In step S204a, the channel correction device performs IFFT processing on the spliced frequency domain correction coefficients.

Fig. 3 is a schematic diagram of extending a frequency domain correction coefficient according to an embodiment of the present application, as shown in fig. 3, a sample point sequence with a length of N _ext obtained by copying and turning over the first N sample points of a frequency domain correction sequence (i.e., a frequency domain correction coefficient) is spliced before the first sample point of an original frequency domain correction sequence, a sample point sequence with a length of N _ext obtained by copying and turning over the last N sample points of the frequency domain correction sequence is spliced after the last sample point of the original frequency domain correction sequence, so as to realize extending the frequency domain correction coefficient.

Illustratively, in conjunction with fig. 3, the frequency domain correction coefficients are extended, and the calculation formula is as follows:

Wherein, For the first sequence of sample points,For the second sample point sequence, μ (1: N _ext) represents the first sample point to the nth _ext sample point of the truncated signal, N _ext is the extension length (i.e., the length of the first N sample points), flip (), indicates that the signal is flipped, i.e., the first point of the signal becomes the last point, and the last point becomes the first point.

Where μ (N _μ-N_ext+1:N_μ) represents the nth _μ-N_ext +1st sample point to nth _μ sample point of the truncated signal, i.e., the last N _ext sample points of μ, flip (), represents flipping the signal.

Wherein, Is a frequency domain correction sequence before extension, namely a frequency domain correction coefficient.

Note that N _ext does not exceed N _μ, and the longer the better.

In the embodiment of the application, the Gibbs effect caused by shortening can be reduced by extending the frequency domain correction coefficient, so that discontinuous or abrupt step of the signal can be avoided.

Taking the example that the frequency domain correction sequence includes 100 sample points as an example, when the frequency domain correction sequence is extended, the first 30 sample points of the frequency domain correction sequence are duplicated, the sequence of the 30 sample points is inverted to obtain sample points to be spliced (namely, a first sample point sequence), the last 30 sample points of the frequency domain correction sequence are duplicated, the sequence of the last 30 sample points is inverted to obtain sample points to be spliced (namely, a second sample point sequence), then the first sample point sequence is spliced before the first sample point of the original frequency domain correction sequence, and the second sample point sequence is spliced after the last sample point of the original frequency domain correction sequence to obtain a spliced frequency domain correction sequence, thereby realizing the extension of the frequency domain correction coefficient.

The above-mentioned inversion of the sample point sequence refers to inverting the order of the sample points in the sample point sequence so as to change the first sample point of the 30 sample points to the last sample point and change the last sample point of the 30 sample points to the first sample point after the inversion.

In the embodiment of the application, the first 30 sample point sequences and the last 30 sample point sequences of the frequency domain correction sequence are intercepted, the intercepted sequences are overturned and spliced with the frequency domain correction sequence, and the prolongation of the frequency domain correction sequence is realized, so that the Gibbs effect caused by shortening can be reduced, and the time domain sampling points obtained after the frequency domain correction sequence is converted from the frequency domain to the time domain are not easy to distort.

Fig. 4A is a schematic diagram of a path loss value of a signal of an RRU channel provided by an embodiment of the present application, and fig. 4B is a schematic diagram of an error vector magnitude provided by an embodiment of the present application. Fig. 4A and fig. 4B show the performance impact on the PDSCH of the downlink physical control channel after the simulation compares the correction filter provided by the embodiment of the present application with the linear fitting scheme, where the filter generated by the present application is set to the 10 th order. The remaining parameter settings are shown in the following table:

Channel(s)	TDL-A
		Modulation scheme	256QAM
Stream number	4
		OFDM symbol number	14
Number of transmitting-end antennas	8
		Number of receiver antennas	4

As shown in fig. 4A and fig. 4B, after the radio frequency signal of the antenna is corrected by the 10 th order correction filter provided by the embodiment of the present application, both the path loss value (i.e., BLER) and the error vector magnitude (i.e., EVM) are significantly reduced and approach to the ideal reciprocity case. After the RRU channel is corrected by the first delay adjustment value and the correction filter according to the embodiment of the present application, compared with the linear fitting first-order filter scheme, the channel correction method according to the embodiment of the present application has a performance gain of 1.5dB, so that the channel correction method according to the embodiment of the present application has a higher gain than the linear fitting method in the related art.

The above description has been made mainly in terms of the channel correction device according to the embodiment of the present application. It will be appreciated that the channel correction means, in order to achieve the above-described functions, comprise corresponding hardware structures and/or software modules performing the respective functions. Those of skill in the art will readily appreciate that the various illustrative algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The embodiment of the application can divide the functional modules of the channel correction device according to the method example, for example, each functional module can be divided corresponding to each function, or two or more functions can be integrated in one processing module. The integrated modules may be implemented in hardware or in software functional modules. It should be noted that, in the embodiment of the present application, the division of the modules is schematic, which is merely a logic function division, and other division manners may be implemented in actual implementation.

Fig. 5 shows a schematic diagram of one possible composition of the channel correction device involved in the above-described embodiment in the case where the respective functional blocks are divided with the respective functions. As shown in fig. 5, the channel calibration device 500 may include a processing module 501, where the processing module 501 is configured to perform delay adjustment on a first radio frequency signal of a first channel of a remote radio unit RRU according to a first delay adjustment value to obtain a second radio frequency signal, and the processing module 501 is further configured to perform filtering processing on the second radio frequency signal through a calibration filter to obtain a third radio frequency signal, where the first delay adjustment value and the calibration filter are determined based on a frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used to correct an amplitude and a phase error of the first channel.

Optionally, in the embodiment of the application, the device further comprises an acquisition module, a processing module and a processing module, wherein the acquisition module is used for acquiring a frequency domain correction coefficient of a first channel of the RRU before performing delay adjustment on a first radio frequency signal of the first channel of the RRU according to a first delay adjustment value, the processing module is further used for performing Inverse Fast Fourier Transform (IFFT) processing on the frequency domain correction coefficient acquired by the acquisition module to obtain a corresponding time domain sampling sequence, the time domain sampling sequence comprises X sampling points, X is a positive integer, and the processing module is further used for determining the first delay adjustment value and a correction filter based on a first sampling point in the X sampling points, and the first sampling point is a sampling point with the largest corresponding amplitude in the X sampling points.

Optionally, in an embodiment of the present application, the processing module is specifically configured to determine the first delay adjustment value according to a preset filter length and an index of the first sampling point in the time domain sampling sequence, where the preset filter length is a preset filter length of the correction filter.

Optionally, in an embodiment of the present application, the processing module is specifically configured to determine a first filter coefficient according to the first L sample points and the last M sample points of the first sample point, and generate a correction filter based on the first filter coefficient, where M is a positive integer less than or equal to X/2, and L is a positive integer less than or equal to X/2.

Optionally, in an embodiment of the present application, the frequency domain correction coefficient includes at least one sample point;

The processing module is further configured to copy and flip the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, copy and flip the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, where N is a positive integer, and splice the first sample point sequence, the second sample point sequence and at least one sample point to obtain a spliced frequency domain correction coefficient, and is specifically configured to perform IFFT processing on the spliced frequency domain correction coefficient.

Optionally, in an embodiment of the present application, the processing module is specifically configured to splice the first sample point sequence to a start position of the at least one sample point, and splice the second sample point sequence to an end position of the at least one sample point, so as to obtain a spliced frequency domain correction coefficient.

Optionally, in an embodiment of the present application, the processing module is specifically configured to input the second radio frequency signal into the correction filter to perform time domain convolution processing, and output the third radio frequency signal.

It should be noted that, all relevant contents of each step related to the above method embodiment may be cited to the functional description of the corresponding functional module, which is not described herein.

An embodiment of the present application provides an electronic device, which is characterized by including a processor and a memory, where the memory stores a program or an instruction executable on the processor, and the program or the instruction implements the steps of the channel correction method in the above embodiment when executed by the processor.

It should be noted that, the specific working process of each functional module in the electronic device provided by the embodiment of the present application may refer to the specific description of the corresponding process in the method embodiment, and the embodiment of the present application is not described in detail herein. The electronic device provided by the embodiment of the application is used for executing the channel correction method, so that the same effect as that of the channel correction method can be achieved.

Embodiments of the present application provide a readable storage medium having stored thereon a program or instructions which, when executed by a processor, implement the steps of the channel correction method as described above.

From the foregoing description of the embodiments, it will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of functional modules is illustrated, and in practical application, the above-described functional allocation may be implemented by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to implement all or part of the functions described above.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and the parts displayed as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of 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 the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

An embodiment of the present application provides a readable storage medium, wherein a program or instructions are stored on the readable storage medium, and the program or instructions, when executed by a processor, implement the steps of the channel correction method according to the above embodiment.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions for causing a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the method described in the embodiments of the present application. The storage medium includes a U disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk, an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A channel correction method, characterized in that the method comprises:

According to the first delay adjustment value, a first radio frequency signal of a first channel of a remote radio frequency unit RRU is delayed adjusted to obtain a second radio frequency signal;

The second radio frequency signal is filtered by a correction filter to obtain a third radio frequency signal;

The first delay adjustment value and the correction filter are determined based on a frequency domain correction coefficient of a first channel of the RRU, and the frequency domain correction coefficient is used to correct an amplitude error and a phase error of the first channel.

2. The method according to claim 1, characterized in that before the delay adjustment is performed on the first RF signal of the first channel of the RRU according to the first delay adjustment value, the method further comprises:

Obtaining a frequency domain correction coefficient of a first channel of the RRU;

Performing inverse fast Fourier transform (IFFT) processing on the frequency domain correction coefficient to obtain a corresponding time domain sampling sequence, wherein the time domain sampling sequence includes X sampling points, where X is a positive integer;

The first time delay adjustment value and the correction filter are determined based on a first sampling point among the X sampling points, where the first sampling point is a sampling point with the largest corresponding amplitude among the X sampling points.

3. The method according to claim 2, wherein determining the first delay adjustment value based on a first sampling point among the X sampling points comprises:

The first delay adjustment value is determined according to a preset filter length and an index of the first sampling point in the time domain sampling sequence, wherein the preset filter length is a preset filter length of the correction filter.

4. The method according to claim 2, characterized in that the determining the correction filter based on the first sampling point among the X sampling points comprises:

The first filter coefficient is determined according to the first L sample value points and the last M sample value points of the first sampling point, and the correction filter is generated based on the first filter coefficient, where L is a positive integer less than or equal to X/2, and M is a positive integer less than or equal to X/2.

5. The method according to claim 2, wherein the frequency domain correction coefficient includes at least one sample point; before performing IFFT processing on the frequency domain correction coefficient, the method further comprises:

Copy and flip the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, and copy and flip the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, where N is a positive integer;

splicing the first sample point sequence, the second sample point sequence and the at least one sample point to obtain a spliced frequency domain correction coefficient;

The performing IFFT processing on the frequency domain correction coefficients includes:

Perform IFFT processing on the spliced frequency domain correction coefficients.

6. The method according to claim 5, characterized in that the step of splicing the first sample point sequence, the second sample point sequence and the at least one sample point to obtain the spliced frequency domain correction coefficient comprises:

The first sampling point sequence is spliced to the starting position of the at least one sampling point, and the second sampling point sequence is spliced to the ending position of the at least one sampling point to obtain the spliced frequency domain correction coefficient.

7. The method according to claim 1, wherein filtering the second radio frequency signal through a correction filter to obtain a third radio frequency signal comprises:

The second radio frequency signal is input into the correction filter for time domain convolution processing, and the third radio frequency signal is output.

8. A channel correction device, characterized in that the device comprises: a processing module;

The processing module is used to perform delay adjustment on a first radio frequency signal of a first channel of a remote radio frequency unit RRU according to a first delay adjustment value to obtain a second radio frequency signal;

The processing module is further configured to filter the second radio frequency signal through a correction filter to obtain a third radio frequency signal;

The first delay adjustment value and the correction filter are determined based on a frequency domain correction coefficient of a first channel of the RRU, and the frequency domain correction coefficient is used to correct amplitude and phase errors of the first channel.

9. An electronic device, characterized in that it comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the channel correction method as described in any one of claims 1 to 7 are implemented.

10. A readable storage medium, characterized in that a program or instruction is stored on the readable storage medium, and when the program or instruction is executed by a processor, the steps of the channel correction method according to any one of claims 1 to 7 are implemented.