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

Abstract

Embodiments of the present application provide a channel correction method and device, electronic equipment and readable storage medium, belonging to the technical field of communication. The channel correction method comprises: adjusting the time delay of 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; filtering 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 to correct the amplitude error and phase error of the first channel.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a channel correction method, apparatus, electronic device, and readable storage medium. Background Technology

[0002] Time-division duplex (TDD) is a type of full-duplex communication technology used in mobile communication systems. A major advantage of TDD systems is that the uplink and downlink air interface channels can be considered reciprocal. This allows the channel response of the corresponding downlink channel to be obtained through the Sounding Reference Signal (SRS), enabling non-codebook precoding of the downlink PDSCH (Physical Downlink Shared Channel), significantly improving its performance.

[0003] However, in actual products, due to various factors such as hardware, the channel response obtained by baseband antennas is affected not only by the air interface channel but also by hardware or external interference, resulting in certain deviations in the amplitude and phase of each antenna. Furthermore, since the transmitting and receiving antennas are not connected by the same circuit, the amplitude and phase errors of each antenna are different. Therefore, when precoding using SRS, the precoding gain cannot be obtained, leading to poor transmission performance. Summary of the Invention

[0004] This application provides a channel correction method, apparatus, electronic device, and medium to solve the problem that the precoding gain cannot be obtained when precoding is performed using SRS, resulting in poor transmission performance.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] A first aspect of this application provides a channel correction method, comprising: adjusting the time delay of 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 filtering the second radio frequency signal through a correction filter to obtain a second radio frequency signal, wherein the first time delay adjustment value is determined by the correction filter based on the frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used to correct the amplitude and phase errors of the first channel.

[0007] The channel correction method provided in this application determines a correction filter and a first time delay adjustment value based on the frequency domain correction coefficient of the first channel of the RRU. The signal delay is adjusted by the first time delay adjustment value, and then the time delay-adjusted signal is filtered by time domain filtering convolution. This realizes the adjustment of the amplitude, phase and delay of the signal in the time domain based on the frequency domain correction coefficient, avoiding the problem that existing time domain correction schemes can only rely on the time delay adjustment granularity supported by the hardware, thereby improving the transmission performance of the channel.

[0008] In conjunction with the first aspect, in one possible implementation, before adjusting the delay of the first radio frequency signal of the first channel of the RRU according to the first delay adjustment value, the channel correction method provided in this application further includes: obtaining the frequency domain correction coefficients of the first channel of the RRU; performing Inverse Fast Fourier Transform (IFFT) processing on the frequency domain correction coefficients to obtain a corresponding time domain sampling sequence, the time domain sampling sequence including X sampling points, where X is a positive integer; determining the first delay adjustment value and the correction filter based on the first sampling point among the X sampling points, wherein the first sampling point is the sampling point with the largest corresponding amplitude among the X sampling points.

[0009] In conjunction with the first aspect and the above possible implementations, in another possible implementation, determining the first time delay adjustment value based on the first sampling point among the X sampling points includes: determining the first time delay adjustment value according to a preset filter length and the index of the first sampling point in the time-domain sampling sequence, wherein the preset filter length is the preset filter length of the correction filter.

[0010] In combination with the first aspect and the above possible implementations, in another possible implementation, determining the correction filter based on the first sampling point among the X sampling points includes: determining the first filter coefficients based on the first L sample points and the last M sample points of the first sampling point, and generating the correction filter based on the first filter coefficients, 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.

[0011] In conjunction with the first aspect and the above possible implementations, in another possible implementation, 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 the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, and copying and flipping the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, where N is a positive integer; concatenating the first sample point sequence, the second sample point sequence, and the at least one sample point to obtain a concatenated frequency domain correction coefficient; the IFFT processing on the frequency domain correction coefficient includes: performing IFFT processing on the concatenated frequency domain correction coefficient.

[0012] In combination with the first aspect and the above possible implementations, in another possible implementation, the step of concatenating the first sample point sequence, the second sample point sequence, and the at least one sample point to obtain the concatenated frequency domain correction coefficients includes: concatenating the first sample point sequence to the starting position of the at least one sample point, and concatenating the second sample point sequence to the ending position of the at least one sample point to obtain the concatenated frequency domain correction coefficients.

[0013] In combination with the first aspect and the above possible implementations, in another possible implementation, the step of filtering the second radio frequency signal through a correction filter to obtain a third radio frequency signal includes: inputting the second radio frequency signal into the correction filter for time-domain convolution processing, and outputting the third radio frequency signal.

[0014] A second aspect of this application provides a channel correction device, comprising: a processing module; the processing module being configured to adjust the time delay of 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; the processing module being further configured to filter the second radio frequency signal through a correction filter to obtain a third radio frequency signal; wherein the first time delay adjustment value is determined by the correction filter based on the frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used to correct the amplitude and phase errors of the first channel.

[0015] The channel correction device provided in this application determines the correction filter and the first time delay adjustment value of each channel based on the frequency domain correction coefficient of each channel of the RRU. Based on the correction filter and the first time delay adjustment value of each channel, the device adjusts the time delay and amplitude and phase error of each channel. In this way, the phase and amplitude of the frequency domain signal can be continuously adjusted by time domain filtering convolution, avoiding the problem that existing time domain correction schemes can only rely on the time delay adjustment granularity supported by the hardware, thereby improving the transmission performance of the channel.

[0016] In conjunction with the second aspect, in one possible implementation, the apparatus further includes: an acquisition module; the acquisition module is configured to acquire the frequency domain correction coefficients of the first channel of the RRU before performing time delay adjustment on the first radio frequency signal of the first channel of the RRU according to the first time delay adjustment value; the processing module is further configured to perform Inverse Fast Fourier Transform (IFFT) processing on the frequency domain correction coefficients acquired by the acquisition module to obtain a corresponding time domain sampling sequence, the time domain sampling sequence including X sampling points, where X is a positive integer; the processing module is further configured to determine the first time delay adjustment value and the correction filter based on the first sampling point among the X sampling points, wherein the first sampling point is the sampling point with the largest corresponding amplitude among the X sampling points.

[0017] In conjunction with the second aspect and the above possible implementations, in another possible implementation, the processing module is specifically used to determine the first time delay adjustment value based on the preset filter length and the index of the first sampling point in the time domain sampling sequence, wherein the preset filter length is the preset filter length of the correction filter.

[0018] In conjunction with the second aspect and the above possible implementations, in another possible implementation, the processing module is specifically used to determine the first filter coefficients based on the first L sample points and the last M sample points of the first sampling point, and to generate the correction filter based on the first filter coefficients, 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.

[0019] In combination with the second aspect and the above possible implementations, in another possible implementation, the frequency domain correction coefficient includes at least one sample point;

[0020] The processing module is further configured to, before performing IFFT processing on the frequency domain correction coefficients, copy and flip the first N sample points of the frequency domain correction coefficients to obtain a first sample point sequence, and copy and flip the last N sample points of the frequency domain correction coefficients to obtain a second sample point sequence, where N is a positive integer; the processing module is further configured to concatenate the first sample point sequence, the second sample point sequence, and the at least one sample point to obtain concatenated frequency domain correction coefficients; the processing module is specifically configured to perform IFFT processing on the concatenated frequency domain correction coefficients.

[0021] In combination with the second aspect and the above possible implementations, in another possible implementation, the processing module is specifically used to splice the first sample point sequence to the starting position of the at least one sample point, and splice the second sample point sequence to the ending position of the at least one sample point, to obtain the spliced ​​frequency domain correction coefficients.

[0022] In conjunction with the second aspect and the above possible implementations, in another possible implementation, the processing module is specifically used to input the second radio frequency signal into the correction filter for time-domain convolution processing and output the third radio frequency signal.

[0023] A third aspect of this application provides an electronic device including a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the channel correction method as described in the first aspect and possible implementations thereof.

[0024] A fourth aspect of this application provides a readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the channel correction method as described in the first aspect and its possible implementations. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A schematic flowchart illustrating the channel correction method provided in this application embodiment;

[0027] Figure 2 A schematic diagram of the time-domain sampling sequence after IFFT provided in an embodiment of this application;

[0028] Figure 3 This is a schematic diagram illustrating the extension of frequency domain correction coefficients according to an embodiment of this application;

[0029] Figure 4A A simulation diagram of the path loss value of the RRU channel provided in the embodiments of this application;

[0030] Figure 4B A simulation diagram of the error vector amplitude of the RRU channel signal provided in the embodiments of this application;

[0031] Figure 5 This is a schematic diagram of a channel correction device provided in an embodiment of this application. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0033] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more.

[0034] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0035] The terms "at least one," "at least one of," etc., used in the specification and claims of this application refer to any one, any two, or a combination of two or more of the included items. For example, at least one of a, b, and c can mean: "a," "b," "c," "a and b," "a and c," "b and c," and "a, b, and c," where a, b, and c can be single or multiple. Similarly, "at least two" refers to two or more items, and its meaning is similar to that of "at least one."

[0036] The following explains some concepts and / or terms involved in the channel correction method provided in the embodiments of this application.

[0037] 1. Multiple-Input Multiple-Output (MIMO) system

[0038] MIMO, also known as Multiple-Input Multiple-Output system, refers to a structure that uses multiple antennas simultaneously at the transmitting and receiving ends. This technology can significantly increase the capacity and spectrum utilization of a communication system without increasing bandwidth, and is a key technology that must be adopted in next-generation mobile communication systems.

[0039] 2. Passage

[0040] This channel refers to the RRU channel or the antenna channel connected to the RRU. RRU channels include single-channel and multi-channel. A single-channel means that the RRU's ports are connected to a single antenna, while a multi-channel means that multiple ports of the RRU are connected to multiple antennas. Based on the signal transmission and reception type, channels can be divided into receive channels and transmit channels.

[0041] 3. Sounding Reference Signal (SRS)

[0042] SRS is used to estimate uplink channel frequency domain information, perform frequency selective scheduling, and estimate uplink channel for downlink beamforming.

[0043] The channel correction method provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0044] For TDD (Time-division Duplex) systems, a major advantage is that the uplink and downlink air interface channels can be considered reciprocal, i.e. Therefore, the channel response of the corresponding downlink channel can be obtained through SRS (Sounding Reference Signal), and the downlink PDSCH (Physical Downlink Shared Channel) can be further precoded without a codebook, which greatly improves its performance.

[0045] However, in actual products, due to various factors such as hardware, the channel response obtained by the baseband, in addition to the air interface channel, is also affected by hardware (or interference), resulting in a certain deviation in the amplitude and phase of each antenna. Furthermore, since the antennas transmit and receive are not connected by the same circuit, the amplitude and phase errors of each antenna are different. Therefore, the channel response obtained by the baseband is:

[0046]

[0047]

[0048] in, For air interface channel, E RX E TX The amplitude and phase deviations caused by each antenna result in H. UL ≠(H DL ) T At this point, when precoding via SRS, the precoding gain cannot be obtained, and antenna correction is required. The antenna correction coefficients are calculated to ensure that:

[0049]

[0050] Meanwhile, in many scenarios, such as those requiring RF combining of antennas, correction can only be performed on each channel in the time domain. In such cases, how to correct the time offset and frequency selection characteristics of each channel becomes a problem.

[0051] The existing technical solution is to perform channel correction using a linear fitting method. However, when adjusting the group delay, the existing linear fitting method can only adjust the delay in integer multiples or can only adjust the adjustment granularity supported by the hardware. Due to the limited adjustment granularity, the adjustment effect is limited, and the related technology ignores the frequency selection characteristics of the channel, resulting in a decrease in performance.

[0052] The channel correction method provided in this application determines a correction filter and a first time delay adjustment value based on the frequency domain correction coefficient of the first channel of the RRU. The signal delay is first adjusted by the first time delay adjustment value, and the phase and amplitude of the frequency domain signal are continuously adjusted by time domain filtering convolution of the time delay-adjusted signal to achieve the effect of adjusting the time delay and amplitude / phase. This avoids the problem that existing time domain correction schemes can only rely on the time delay adjustment granularity supported by the hardware. Moreover, compared with existing schemes, the frequency selectivity of the device is corrected by this correction filter, thereby improving the correction effect and improving the transmission performance of the channel.

[0053] Figure 1 A flowchart of a channel correction method provided in this application embodiment is shown below. Figure 1 As shown, the channel calibration method may include the following steps S201 and S202:

[0054] Step S201: The channel correction device adjusts the time delay of the first radio frequency signal of the first channel of the remote radio frequency unit RRU according to the first time delay adjustment value to obtain the second radio frequency signal.

[0055] The aforementioned first time delay adjustment value is determined based on the frequency domain correction coefficient of the first channel of the RRU.

[0056] Optionally, in this embodiment of the application, the channel correction device can convert the above-mentioned frequency domain correction coefficients to the time domain through IFFT transformation, and determine the first time delay adjustment value based on the amplitude peak value of the sampling points in the time domain.

[0057] Optionally, in the embodiments of this application, the first channel can be the signal transmission channel of the RRU of the first cell, or the first channel can be the signal reception channel of the RRU of the first cell.

[0058] Optionally, in this embodiment of the application, the first channel may include multiple channels.

[0059] For example, cell 1 has two RRUs that form a DMIMO network. The two RRUs are RRU1 and RRU2. Both RRU1 and RRU2 have two antenna channels. Each antenna channel is used for receiving or transmitting radio frequency signals. The first channel mentioned above may include the two antenna channels of RRU1 and the two antenna channels of RRU2.

[0060] Optionally, in this embodiment of the application, the first radio frequency signal may be a radio frequency signal transmitted through the first channel.

[0061] Optionally, in this embodiment of the application, the second radio frequency signal can be a radio frequency signal with a delay less than a threshold obtained by adjusting the delay of the first radio frequency signal.

[0062] Step S202: The channel correction device filters the second radio frequency signal through a correction filter to obtain the third radio frequency signal.

[0063] The aforementioned correction filter is determined based on the frequency domain correction coefficients of the first channel of the RRU.

[0064] Optionally, in this embodiment of the application, the channel correction device can convert the above-mentioned frequency domain correction coefficients to the time domain through IFFT transformation, and calculate the filter coefficients based on the amplitude / phase characteristics of the sampling points in the time domain, thereby obtaining the correction filter.

[0065] Optionally, in this embodiment of the application, the above-mentioned correction filter is used to correct the amplitude error and phase error of the first channel.

[0066] Optionally, in this embodiment of the application, the channel correction device performs time-domain convolution processing on the second radio frequency signal input correction filter and outputs a third radio frequency signal.

[0067] For example, after inputting the radio frequency (RF) signal into a correction filter, the coefficients of the correction filter are convolved with the RF signal in the time domain (i.e., multiplied and accumulated), and the processed RF signal is output. In this way, by using time-domain filtering and convolution, the amplitude and phase of the signal can be adjusted to obtain an RF signal with the required amplitude / phase characteristics.

[0068] For example, taking the first time delay adjustment value as τ and the correction filter as f, the signal to be corrected in the RRU channel is first adjusted by an integer multiple of τ time delay to obtain the adjusted signal x′. Then, the adjusted signal x′ is corrected using the calculated filter, as shown in the following expression:

[0069]

[0070] Where x is the signal to be corrected. The signal is rectified, τ is the integer multiple of the time delay adjustment, f is the correction filter, and ⊙ represents the convolution operation.

[0071] It should be noted that in a multi-channel RRU, inconsistencies in frequency response caused by phase and gain differences, aging, and amplitude / phase characteristic distortion of a series of devices will all result in time-varying errors in the channels. This will lead to significant differences between the actual and ideal channels, affecting the overall system performance. Therefore, a channel correction function is needed. This application embodiment uses channel correction to track and compensate for channel delays and their amplitude / phase characteristics, making them more consistent with the amplitude / phase characteristics of the reference channel, reducing channel errors, and meeting the system's accuracy requirements.

[0072] The channel correction method provided in this application involves a channel correction device determining the correction filter and the first time delay adjustment value for each channel based on the frequency domain correction coefficients of each channel of the RRU. Based on the correction filter and the first time delay adjustment value, the device adjusts the time delay and amplitude-phase error of each channel. This allows for continuous adjustment of the phase and amplitude of the frequency domain signal through time-domain filtering convolution, avoiding the limitation of existing time-domain correction schemes that rely solely on the time delay adjustment granularity supported by hardware, thereby improving the transmission performance of the channel.

[0073] Optionally, in this embodiment of the application, before step S201, the channel correction method provided in this embodiment of the application further includes the following steps S203 to S205:

[0074] Step S203: The channel correction device obtains the frequency domain correction coefficient of the first channel of the RRU.

[0075] Step S204: The channel correction device performs Inverse Fast Fourier Transform (IFFT) processing on the above frequency domain correction coefficients to obtain the corresponding time domain sampling sequence.

[0076] The aforementioned time-domain sampling sequence includes X sampling points, where X is a positive integer.

[0077] Step S205: The channel correction device determines the first time delay adjustment value and the correction filter based on the first sampling point among the above X sampling points.

[0078] Among them, the first sampling point is the sampling point with the largest corresponding amplitude among the above X sampling points.

[0079] Optionally, in the embodiments of this application, the channel correction device can obtain the frequency domain correction coefficients by sending a frequency domain correction sequence based on the LS algorithm or the Argos algorithm.

[0080] For example, assume there are two RRUs in a DMIMO network, denoted as RRU1 and RRU2, each with two antenna channels. The calculation process for the frequency domain correction coefficient is as follows: RRU1 transmits a pilot signal, RRU2 receives the pilot signal, performs channel estimation to obtain the channel response from RRU1 to RRU2, RRU2 transmits a pilot signal, RRU2 receives the pilot signal, performs channel estimation to obtain the channel response from RRU2 to RRU2, and then calculates the correction value (i.e., frequency domain correction coefficient) for RRU2's antenna and the correction value for RRU2's antenna based on the channel responses from RRU1 to RRU2 and from RRU2 to RRU2.

[0081] It should be noted that the specific process of obtaining the frequency domain correction coefficients by sending the frequency domain correction sequence can be found in the description of related technologies, and will not be repeated in this embodiment.

[0082] Optionally, in this embodiment, the channel correction device performs IFFT processing on the frequency domain correction coefficients to obtain the time domain correction sequence corresponding to the frequency domain correction coefficients. The expression for IFFT processing of the frequency domain correction coefficients is as follows:

[0083]

[0084] Where I is the result after IFFT, and N IFFT The number of points in the IFFT is represented by μ, which is the frequency domain correction coefficient.

[0085] Optionally, in the embodiments of this application, the above-mentioned X sampling points correspond to X amplitudes.

[0086] For example, after performing an IFFT on the frequency domain correction coefficients, an N-point complex number is obtained, the magnitude of which is the amplitude characteristic of the original signal at that time delay value.

[0087] It should be noted that when performing IFFT processing, the input signal is the frequency domain correction coefficient, while the output is the correction coefficient for each time delay value.

[0088] Optionally, in this embodiment of the application, the channel correction device can search for the amplitude peak value of X sampling points, determine the sampling point with the largest amplitude among the X sampling points (i.e., the first sampling point), and obtain the subscript (i.e., index) of the sampling point in the time domain sampling sequence.

[0089] It is understandable that the subscript or index of a sampling point in the time-domain sampling sequence can characterize the position of that sampling point in the entire sequence.

[0090] Optionally, in this embodiment of the application, the channel correction device can calculate the filter coefficients based on the amplitude and phase information of the first sampling point to obtain the correction filter.

[0091] Optionally, in this embodiment of the application, the channel correction device may calculate the first time delay adjustment value based on the index of the first sampling point.

[0092] Optionally, in this embodiment of the application, the process of determining the first time delay adjustment value based on the first sampling point among the X sampling points in step S204 above may include the following step S204a:

[0093] Step S204a: The channel correction device determines the first time delay adjustment value based on the preset filter length and the index of the first sampling point in the above time domain sampling sequence.

[0094] The preset filter length is the preset filter length of the correction filter.

[0095] Optionally, in the embodiments of this application, the preset filter length can be an empirical value. The preset filter length is related to the correction performance and acceptable complexity, and can be obtained through simulation.

[0096] For example, the preset filter length can be 10.

[0097] Optionally, in this embodiment of the application, the first delay adjustment value can be an integer.

[0098] Optionally, in this embodiment of the application, after obtaining the time-domain correction sequence, the channel correction device searches for the sampling point with the largest amplitude among the X sampling points of the time-domain correction sequence, and calculates the first time delay adjustment value based on the index of the sampling point and the preset filter length.

[0099] For example, after obtaining the time-domain sampling sequence I, the peak value of I is searched, where the index corresponding to the largest peak is IDX. Further, if IDX is less than half the number of points in the IFFT, the difference between IDX and half the preset filter length is used as the first time delay adjustment value; or, if IDX is greater than half the number of points in the IFFT, the difference between IDX, the number of points in the IFFT, and half the preset filter length is used as the first time delay adjustment value, calculated as follows:

[0100]

[0101] Where, N IFFT N is the number of points in the IFFT. fliterLen τ is the filter length, and τ is the first time delay adjustment value.

[0102] Optionally, in this embodiment, the process of determining the correction filter based on the first sampling point among the X sampling points in step S204 may include the following step S204b:

[0103] Step S204b: The channel correction device determines the first filter coefficients based on the first L sample points and the last M sample points of the first sampling point, and generates the correction filter based on the first filter coefficients.

[0104] 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.

[0105] Optionally, in this embodiment, the number of L sample points and M sample points is determined according to a preset filter length. Optionally, L and M are less than or equal to the preset filter length.

[0106] For example, the preset filter length N fliterLen If the value is 10, then L sample points and M sample points together comprise 10 sampling points. For example, L sample points and M sample points can each comprise 5 sample points, or L sample points can comprise 7 sample points and M sample points can comprise 3 sample points, or L sample points can comprise 3 sample points and M sample points can comprise 7 sample points.

[0107] It should be noted that the number of L and M sample points listed in the above embodiments is only one possible example. The specific number of sample points can be set according to actual needs, and this application embodiment does not limit this.

[0108] For example, Figure 2 This is a schematic diagram of the time-domain sampling sequence after IFFT provided in an embodiment of this application. Figure 2 The horizontal axis represents the index of the sampling point. Figure 2 This shows 150 sampling points, with an index range of 0-150. The vertical axis represents the amplitude corresponding to each sampling point. Figure 2 As shown, the first L sample points can be the first 4 sample points of the first sampling point, and the first M sample points can be the last 5 sample points of the first sampling point; or, the first L sample points can be the first 5 sample points of the first sampling point, and the first M sample points can be the last 4 sample points of the first sampling point.

[0109] It should be noted that, Figure 2 The sampling points in the solid box are the first L sample points and the last M sample points selected.

[0110] For example, after obtaining the time-domain sampling sequence I, based on the searched amplitude peak, take N values ​​to the left and right of the peak. fliterLenThe data is used as the filter coefficients of the correction filter, and the calculation formula is as follows:

[0111]

[0112] Where I is the IFFT result, IDX is the index corresponding to the maximum peak of |I|, and N is the index of the maximum peak of |I|. fliterLen Here, f is the filter length, and f is the correction filter. This indicates rounding down. This indicates rounding up to the nearest integer.

[0113] Optionally, in this embodiment, the frequency domain correction coefficient includes at least one sample point; prior to step S204, the channel correction method provided in this embodiment further includes steps S206 and S207:

[0114] Step S206: The channel correction device copies and flips the first N sample points of the frequency domain correction coefficient to obtain the first sample point sequence, and copies and flips the last N sample points of the frequency domain correction coefficient to obtain the second sample point sequence.

[0115] Where N is a positive integer.

[0116] 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 the spliced ​​frequency domain correction coefficients.

[0117] Combining steps S206 and S207 above, the process of performing IFFT processing on the frequency domain correction coefficients in step S204 may include the following step S204a:

[0118] Step S204a: The channel correction device performs IFFT processing on the spliced ​​frequency domain correction coefficients.

[0119] Figure 3 This is a schematic diagram illustrating the extension of the frequency domain correction coefficients provided in an embodiment of this application, as shown below. Figure 3 As shown, the length of the sequence obtained by copying and flipping the first N sample points of the frequency domain correction sequence (i.e., frequency domain correction coefficients) is N. ext The sample point sequence is concatenated before the first sample point of the original frequency domain correction sequence. The last N sample points of the frequency domain correction sequence (i.e., frequency domain correction coefficients) are copied and flipped to obtain a sequence of length N. ext The sample point sequence is spliced ​​after the last sample point of the original frequency domain correction sequence to obtain the spliced ​​frequency domain correction sequence, thereby realizing the extension of the frequency domain correction coefficients.

[0120] For example, in conjunction with the above Figure 3 The frequency domain correction coefficients are extended and calculated using the following formula:

[0121]

[0122]

[0123] in, For the first isomorphic point sequence, For the second sample point sequence, μ(1:N) ext ) indicates that the first sample point of the signal is captured up to the Nth sample point. ext N sample points ext The extension length (i.e., the length of the first N sample points) is given by `flip(.)`, which means flipping the signal, i.e., the first point of the signal becomes the last point, and the last point becomes the first point.

[0124] Where, μ(N) μ -N ext +1:N μ ), indicating that the Nth digit of the intercepted signal is captured. μ -N ext +1 sample points to the Nth μ Each sample point, i.e., the last N of μ. ext For each sample point, flip(.) indicates that the signal is flipped.

[0125]

[0126] in, This is the frequency domain correction sequence before extension, i.e., the frequency domain correction coefficients.

[0127] It should be noted that N ext No more than N μ And the longer the better.

[0128] In the embodiments of this application, by extending the frequency domain correction coefficients, the Gibbs effect caused by truncation can be reduced, thereby avoiding signal discontinuity or sudden step jumps.

[0129] For example, taking a frequency domain correction sequence comprising 100 sample points as an example, when extending the frequency domain correction sequence, the first 30 sample points of the frequency domain correction sequence are copied and their order is reversed to obtain sample points to be spliced ​​(i.e., the first sample point sequence). The last 30 sample points of the frequency domain correction sequence are copied and their order is reversed to obtain sample points to be spliced ​​(i.e., the 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 the spliced ​​frequency domain correction sequence, thereby realizing the extension of the frequency domain correction coefficients.

[0130] It should be noted that flipping the above sample point sequence refers to flipping the order of the sample points in the sample point sequence, so that after flipping, the first sample point of the 30 sample points becomes the last sample point, and the last sample point of the 30 sample points becomes the first sample point.

[0131] In this embodiment, by extracting the first 30 sample points and the last 30 sample points of the frequency domain correction sequence, and then flipping the extracted sequence and splicing it with the frequency domain correction sequence, the extension of the frequency domain correction sequence is achieved. This reduces the Gibbs effect caused by truncation, making the time domain sampling points obtained after the frequency domain correction sequence is converted from the frequency domain to the time domain less prone to distortion.

[0132] Figure 4A This is a schematic diagram illustrating the path loss values ​​of the RRU channel provided in this embodiment of the application. Figure 4B This is a schematic diagram of the error vector magnitude provided in an embodiment of this application. Figure 4A and Figure 4B The simulation compares the impact of correction using the correction filter provided in this application and the linear fitting scheme on the performance of the downlink physical control channel (PDSCH). The filter generated in this application is set to order 10. Other parameter settings are shown in the table below.

[0133] Channel TDL-A Modulation method 256QAM Number of streams 4 Number of OFDM symbols 14 Number of transmitting antennas 8 Number of antennas at the receiver 4

[0134] like Figure 4A and Figure 4B As shown, after correcting the antenna's RF signal using the 10th-order correction filter provided in this application embodiment, both the path loss value (BLER) and the error vector amplitude (EVM) are significantly reduced and approach the ideal reciprocity condition. After correcting the RRU channel using the first delay adjustment value and correction filter in this application embodiment, there is a 1.5dB performance gain compared to the first-order filter scheme of linear fitting. Therefore, the channel correction method provided in this application embodiment has a higher gain than the linear fitting method in related technologies.

[0135] The foregoing mainly describes the solutions provided in the embodiments of this application from the perspective of a channel correction device. It is understood that, in order to achieve the above functions, the channel correction device includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the algorithm steps of the various examples described in the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art 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.

[0136] This application embodiment can divide the channel correction device into functional modules according to the above method example. For example, each function can be divided into its own functional module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or as a software functional module. It should be noted that the module division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0137] When dividing each function into modules according to its corresponding function. Figure 5 A schematic diagram of a possible composition of the channel correction device involved in the above embodiments is shown. For example... Figure 5 As shown, the channel correction device 500 may include: a processing module 501; wherein the processing module 501 is used to adjust the time delay of the first radio frequency signal of the first channel of the remote radio frequency unit (RRU) according to a first time delay adjustment value to obtain a second radio frequency signal; the processing module 501 is also used to filter the second radio frequency signal through a correction filter to obtain a third radio frequency signal; wherein the first time delay adjustment value is determined by the correction filter based on the frequency domain correction coefficient of the first channel of the RRU, and the frequency domain correction coefficient is used to correct the amplitude and phase error of the first channel.

[0138] Optionally, in this embodiment of the application, the above-mentioned apparatus further includes: an acquisition module; the acquisition module is configured to acquire the frequency domain correction coefficient of the first channel of the RRU before performing time delay adjustment on the first radio frequency signal of the first channel of the RRU according to the first time 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, the time domain sampling sequence including X sampling points, where X is a positive integer; the processing module is further configured to determine the first time delay adjustment value and the correction filter based on the first sampling point among the X sampling points, wherein the first sampling point is the sampling point with the largest corresponding amplitude among the X sampling points.

[0139] Optionally, in this embodiment of the application, the above-mentioned processing module is specifically used to determine the first time delay adjustment value according to the preset filter length and the index of the first sampling point in the time domain sampling sequence, wherein the preset filter length is the preset filter length of the above-mentioned correction filter.

[0140] Optionally, in this embodiment of the application, the above-mentioned processing module is specifically used to determine the first filter coefficients based on the first L sample points and the last M sample points of the first sampling point, and generate a correction filter based on the first filter coefficients, 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.

[0141] Optionally, in the embodiments of this application, the frequency domain correction coefficients include at least one sampling point;

[0142] The aforementioned processing module is further configured to, before performing IFFT processing on the aforementioned frequency domain correction coefficients, copy and flip the first N sample points of the aforementioned frequency domain correction coefficients to obtain a first sample point sequence, and copy and flip the last N sample points of the aforementioned frequency domain correction coefficients to obtain a second sample point sequence, where N is a positive integer; the aforementioned processing module is further configured to concatenate the first sample point sequence, the second sample point sequence, and at least one sample point to obtain concatenated frequency domain correction coefficients; the aforementioned processing module is specifically configured to perform IFFT processing on the concatenated frequency domain correction coefficients.

[0143] Optionally, in this embodiment of the application, the above-mentioned processing module is specifically used to splice the first sample point sequence to the starting position of the at least one sample point, and splice the second sample point sequence to the ending position of the at least one sample point, so as to obtain the spliced ​​frequency domain correction coefficient.

[0144] Optionally, in this embodiment of the application, the above-mentioned processing module is specifically used to input the second radio frequency signal into the above-mentioned correction filter for time-domain convolution processing and output the third radio frequency signal.

[0145] The channel correction device provided in this application determines the correction filter and the first time delay adjustment value of each channel based on the frequency domain correction coefficient of each channel of the RRU. Based on the correction filter and the first time delay adjustment value of each channel, the device adjusts the time delay and amplitude and phase error of each channel. In this way, the phase and amplitude of the frequency domain signal can be continuously adjusted by time domain filtering convolution, avoiding the problem that existing time domain correction schemes can only rely on the time delay adjustment granularity supported by the hardware, thereby improving the transmission performance of the channel.

[0146] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0147] This application provides an electronic device, characterized in that it includes a processor and a memory, wherein the memory stores programs or instructions that can run on the processor, and when the programs or instructions are executed by the processor, they implement the steps of the channel correction method in the above embodiments.

[0148] It should be noted that the specific working process of each functional module in the electronic device provided in this application embodiment can be referred to the specific description of the corresponding process in the method embodiment, and will not be repeated in detail here. The electronic device provided in this application embodiment is used to perform the above-described channel correction method, and therefore can achieve the same effect as the above-described channel correction method.

[0149] This application provides a readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the channel correction method described above.

[0150] Through the above description of the embodiments, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0151] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0152] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0153] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0154] This application provides a readable storage medium, characterized in that a program or instructions are stored on the readable storage medium, and when the program or instructions are executed by a processor, the steps of the channel correction method as described in the above embodiments are implemented.

[0155] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of this application embodiment, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0156] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A channel correction method characterized by, The method comprises: obtaining a frequency domain correction coefficient of a first channel of a remote radio unit (RRU); performing inverse fast Fourier transform (IFFT) processing on the frequency domain correction coefficient to obtain a corresponding time domain sample sequence, the time domain sample sequence comprising X sample points, X being a positive integer; determining a first time delay adjustment value and a correction filter based on a first sample point in the X sample points, the first sample point being a sample point with the largest amplitude in the X sample points; performing time delay adjustment on a first radio frequency signal of the first channel of the RRU according to the first time delay adjustment value to obtain a second radio frequency signal; performing filter processing on the second radio frequency signal through the correction filter to obtain a third radio frequency signal; wherein the frequency domain correction coefficient is used to correct amplitude error and phase error of the first channel.

2. The method of claim 1, wherein, The determination of the first time delay adjustment value based on the first sample point in the X sample points comprises: determining the first time delay adjustment value according to a preset filter length and an index of the first sample point in the time domain sample sequence, the preset filter length being a preset filter length of the correction filter.

3. The method of claim 1, wherein, The determination of the correction filter based on the first sample point in the X sample points comprises: determining a first filter coefficient according to the first L sample points and the last M sample points of the first sample point, and generating the correction filter based on the first filter coefficient, L being a positive integer less than or equal to X / 2, and M being a positive integer less than or equal to X / 2.

4. The method of claim 1, wherein, The frequency domain correction coefficient comprises at least one sample point; before the IFFT processing on the frequency domain correction coefficient, the method further comprises: copying and flipping the first N sample points of the frequency domain correction coefficient to obtain a first sample point sequence, and copying and flipping the last N sample points of the frequency domain correction coefficient to obtain a second sample point sequence, N being a positive integer; splicing the first sample point sequence, the second sample point sequence and the at least one sample point to obtain spliced frequency domain correction coefficient; The IFFT processing on the frequency domain correction coefficient comprises: performing IFFT processing on the spliced frequency domain correction coefficient.

5. The method of claim 4, wherein, The splicing of the first sample point sequence, the second sample point sequence and the at least one sample point to obtain spliced frequency domain correction coefficient comprises: splicing the first sample point sequence to the starting position of the at least one sample point, and splicing the second sample point sequence to the ending position of the at least one sample point to obtain spliced frequency domain correction coefficient.

6. The method of claim 1, wherein, The filter processing on the second radio frequency signal through the correction filter to obtain the third radio frequency signal comprises: inputting the second radio frequency signal into the correction filter for time domain convolution processing to output the third radio frequency signal.

7. A channel correction device, characterized by The device comprises a processing module; an obtaining module configured to obtain a frequency domain correction coefficient of a first channel of a remote radio unit (RRU); The processing module is configured to perform inverse fast Fourier transform (IFFT) on the frequency domain correction coefficient to obtain a corresponding time domain sampling sequence, the time domain sampling sequence including X sampling points, X being a positive integer; The processing module is further configured to determine a first time delay adjustment value and a correction filter based on a first sampling point in the X sampling points, the first sampling point being a sampling point with the largest amplitude in the X sampling points; The processing module is further configured to perform time delay adjustment on a first radio frequency signal of a first channel of the RRU according to the first time delay adjustment value to obtain a second radio frequency signal; The processing module is further configured to perform filtering processing on the second radio frequency signal through the correction filter to obtain a third radio frequency signal; The frequency domain correction coefficient is used to correct amplitude and phase errors of the first channel.

8. An electronic device, comprising: A processor and a memory are included, the memory storing a program or instructions executable on the processor, the program or instructions being executed by the processor to implement steps of the channel correction method according to any one of claims 1 to 6.

9. A readable storage medium, characterized by, A program or instructions are stored on the readable storage medium, the program or instructions being executed by the processor to implement steps of the channel correction method according to any one of claims 1 to 6.

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