A method and system for synthesizing multi-channel nonlinear phase signals

Abstract

This invention discloses a method and system for synthesizing multi-channel nonlinear phase signals. The method includes: controlling multiple channels to acquire data sequentially by frequency; controlling a two-to-one switch to switch to a calibration signal source and simultaneously sending a signal to multiple channels; obtaining the precise frequency offset of each channel and calculating the frequency position of the synthesized signal in the baseband; obtaining the precise time difference and amplitude difference of each channel; calculating and writing the mixing cosine and sin phase values ​​into memory based on the frequency position of each channel in the synthesized baseband; controlling the two-to-one switch to switch the antenna to receive the real signal; performing calculations on each channel based on the preprocessed offset values, and merging the processed channel data into a single signal. This solution does not rely on complex hardware design to achieve high-precision time or frequency control, and can achieve rapid synthesis of multiple signals at low cost through digital algorithms.

Description

Technical Field

[0001] This invention relates to the field of real-time software synthesis and acquisition technology of multi-channel signals in non-cooperative communication, and particularly to a method and system for synthesizing multi-channel nonlinear phase signals. Background Technology

[0002] In non-cooperative communication, frequency hopping technology is widely used to ensure communication security and anti-interference. With the continuous development of frequency hopping technology, the frequency hopping speed is getting faster and the frequency hopping range is getting wider. In addition, for high-bandwidth communication signals, especially satellite data transmission signals, there is a huge communication bandwidth, which leads to the need for larger real-time processing bandwidth of acquisition and receiving equipment. Due to the limitations of ADC technology development and hardware cost considerations, a multi-channel ADC acquisition hardware method is generally used to synthesize a single high-bandwidth signal.

[0003] Existing hardware signal synthesis methods can be broadly categorized into two types: one uses time-interleaving technology to allow multiple ADCs to sample the input signal alternately in a specific time sequence. Precise timing control ensures the accuracy and consistency of sampling times for each ADC, thus accurately reconstructing the input signal. The other type uses frequency division multiplexing (FDM) technology to divide the input signal into sub-signals of different frequency bands. Each sub-signal is then assigned to a corresponding ADC for sampling, and finally, the sub-signals are reconstructed and synthesized into the original high-bandwidth signal.

[0004] The first type of method is characterized by the critical importance of precise timing control. It is essential to ensure that each ADC samples strictly according to the set time sequence. Deviations in the sampling time can lead to errors in the sampled data or signal distortion. In addition, since different ADCs may have differences in parameters such as bias and gain, these parameters also need to be calibrated to ensure the accuracy and reliability of the synthesized sampling results. The second type of method is characterized by the need for a reasonable design of the frequency division multiplexing filter bank to accurately divide the signal into appropriate frequency bands for ADC sampling. Furthermore, it is necessary to accurately restore and synthesize the sub-signals sampled by each ADC into the original signal. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method and system for synthesizing multi-channel nonlinear phase signals, and offers a convenient and effective software method for synthesizing multiple signals, enabling rapid synthesis of multiple signals.

[0006] This invention is achieved using the following technical solution: a multi-channel nonlinear phase signal synthesis method, comprising the following steps:

[0007] Step S1: Control multiple channels to collect data in frequency order, and perform coarse time synchronization of the data after GPS / BD time synchronization;

[0008] Step S2: Control the two-way switch to switch to the calibration signal source, and send a signal to multiple channels simultaneously;

[0009] Step S3: Perform FFT calculation on the multi-channel acquired signals and find the maximum value to obtain the precise frequency offset of each channel. Then, combine the actual acquisition frequency of each channel to calculate the frequency position of the synthesized signal in the baseband.

[0010] Step S4: Perform correlation calculations on the multi-channel acquired signals to obtain the precise time difference and amplitude difference of each channel;

[0011] Step S5: Calculate the mixing cosine and sin phase values ​​based on the frequency position of each channel in the synthesized baseband, write the table into memory, and control the two-way switch to switch the antenna to receive the real signal.

[0012] Step S6: Perform calculations on each channel based on the deviation value obtained from preprocessing, and merge the processed data from each channel into one signal.

[0013] Specifically, the calculation of the frequency position in step S3 includes:

[0014] Step S31: Set the calibrated center frequency according to the bandwidth and signal frequency of each of the n channels;

[0015] Step S32: Start data acquisition to obtain the effective frequency range of n baseband data streams;

[0016] Step S33: After n times resampling, perform frequency mixing, shift the spectrum according to the preset frequency, and finally add the data to complete the merging.

[0017] Specifically, step S3 further includes:

[0018] The spectrum data of each channel is obtained by performing a short-time four-factor transformation with the same parameters on the multi-channel acquired signals and holding the signal for maximum. The frequency deviation of each channel is obtained by finding the maximum value of the single-tone signal sent by the signal source.

[0019] By comparing the time codes in the data of each channel, the time of each channel is initially synchronized, and then the precise phase difference of each channel is obtained through relevant algorithms.

[0020] Specifically, the phase difference, after being converted into time, becomes the precise time difference of the channel. Taking the first channel as the reference channel, the phase difference of the other channels relative to the reference channel is calculated, and the value is the maximum correlation value obtained by different channel data at different offsets.

[0021] Specifically, the relevant algorithms include:

[0022] Let the sliding window size be n, and let x and y represent two different channel data sequences. The correlation when the window slides to the k-th point of the target channel data is:

[0023]

[0024] in and s is the mean of the sampled signal points window. x and s y x is the standard deviation. i and y i γ is the i-th offset point relative to the starting position of the sliding window. k The value range is [-1, +1];

[0025] Let γ pq =max{γ k ,k=0,1,2,3…}|0.8≤γ k The optimal correlation point for the signal is given by p, where p is the offset of the optimal alignment position relative to the starting data of the target channel, and q is the offset of the sliding window of the reference channel relative to the starting data. The phase difference between the reference channel and the target channel is then calculated as follows:

[0026] Time difference

[0027] Specifically, step S6, which performs computational processing on each channel using OpenCL for parallel computation acceleration, includes the following sub-steps:

[0028] Step S61: Calculate the data sampling rate of the combined signal based on the data sampling rate R of each channel;

[0029] Step S62: Upsample the data of each channel by an integer multiple, and perform interpolation filtering without extraction;

[0030] Step S63: Perform frequency mixing processing on the upsampled data of each channel, and complete the frequency mixing calculation by looking up the cos and sin values ​​in the memory table;

[0031] Step S64: Calculate the amplitude mean of the mixed data for each channel;

[0032] Step S65: Calculate the delay of each channel based on the precise phase time difference and correct the phase delay;

[0033] Step S66: Use addition to merge the sampling points of each channel.

[0034] Specifically, step S64, the mean amplitude calculation, further includes: recalculating the data amplitude values, using the first channel as a reference, and recalculating the data amplitude values ​​of the other channels.

[0035] A multi-channel nonlinear phase signal synthesis system, comprising:

[0036] The host computer module processes the data collected from each channel in real time based on the preprocessed parameters and sends instructions to the digital card module and the switch module.

[0037] Digital card module: Receives instructions from the host computer to control the underlying AD card and signal source, and reports the collected raw data to the host computer;

[0038] Switching module: Switches between the calibration signal source and the actual antenna receiving the real signal according to instructions;

[0039] Data processing module: Located in the host computer module, the GPU performs computational density processing, and the CPU performs logical processing.

[0040] Specifically, the transmission of instructions from the host computer module includes: sending instructions to the digital card control signal source via PCIE or network to complete calibration preprocessing to obtain the time difference, frequency difference, and amplitude difference of each channel, and then sending instructions to switch the two-to-one switch to the actual antenna to receive the real signal.

[0041] The beneficial effects of the present invention are as follows: The present invention does not rely on complex hardware design to achieve high-precision control of time or frequency. It can achieve rapid synthesis of multiple signals at low cost through digital algorithm. At the same time, it can quickly synthesize multiple signals. Compared with other synthesis methods, this method has the following advantages: (1) Compared with conventional time interleaving technology and frequency division multiplexing and other hardware ADC combining technology, this method can save hardware design costs; (2) Compared with conventional software synthesis algorithms, this method has higher performance and can realize real-time synthesis of multiple signals with bandwidth of hundreds of megabits; (3) This method can be implemented on conventional CPU+GPU multi-channel acquisition equipment without the need for any special processing equipment. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of multi-channel signal synthesis in an embodiment of the present invention;

[0044] Figure 2 This is a schematic diagram of data processing for each channel in an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of frequency offset calculation for three-channel signal synthesis in an embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0047] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0048] The following is in conjunction with the appendix Figures 1-3 The following describes some embodiments of the present invention in detail. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0049] This invention proposes a multi-channel nonlinear phase signal synthesis system. In one embodiment, a multi-channel nonlinear phase signal synthesis method includes the following steps:

[0050] Step S1: Control multiple channels to collect data in frequency order, and perform coarse time synchronization of the data after GPS / BD time synchronization;

[0051] Step S2: Control the two-way switch to switch to the calibration signal source, and send a signal to multiple channels simultaneously;

[0052] Step S3: Perform FFT calculation on the multi-channel acquired signals and find the maximum value to obtain the precise frequency offset of each channel. Then, combine the actual acquisition frequency of each channel to calculate the frequency position of the synthesized signal in the baseband.

[0053] Step S4: Perform correlation calculations on the multi-channel acquired signals to obtain the precise time difference and amplitude difference of each channel;

[0054] Step S5: Calculate the mixing cosine and sin phase values ​​based on the frequency position of each channel in the synthesized baseband, write the table into memory, and control the two-way switch to switch the antenna to receive the real signal.

[0055] Step S6: Perform calculations on each channel based on the deviation value obtained from preprocessing, and merge the processed data from each channel into one signal.

[0056] In this embodiment, the calculation of the frequency position in step S3 specifically includes:

[0057] Step S31: Set the calibrated center frequency according to the bandwidth and signal frequency of each of the n channels;

[0058] Step S32: Start data acquisition to obtain the effective frequency range of n baseband data streams;

[0059] Step S33: After n times resampling, perform frequency mixing, shift the spectrum according to the preset frequency, and finally add the data to complete the merging.

[0060] In this embodiment, step S3 further includes:

[0061] The spectrum data of each channel is obtained by performing a short-time four-factor transformation with the same parameters on the multi-channel acquired signals and holding the signal for maximum. The frequency deviation of each channel is obtained by finding the maximum value of the single-tone signal sent by the signal source.

[0062] By comparing the time codes in the data of each channel, the time of each channel is initially synchronized, and then the precise phase difference of each channel is obtained through relevant algorithms.

[0063] In this embodiment, the phase difference is converted into time, which is the precise time difference of the channel. Taking the first channel as the reference channel, the phase difference of the other channels relative to the reference channel is calculated. The value is the maximum correlation value obtained by different channel data at different offsets.

[0064] In this embodiment, the relevant algorithm specifically includes:

[0065] Let the sliding window size be n, and let x and y represent two different channel data sequences. The correlation when the window slides to the k-th point of the target channel data is:

[0066]

[0067] in and s is the mean of the sampled signal points window. x and s y x is the standard deviation. i and y i γ is the i-th offset point relative to the starting position of the sliding window. k The value range is [-1, +1];

[0068] Let γ pq =max{γ k ,k=0,1,2,3…}|0.8≤γ k The optimal correlation point for the signal is given by p, where p is the offset of the optimal alignment position relative to the starting data of the target channel, and q is the offset of the sliding window of the reference channel relative to the starting data. The phase difference between the reference channel and the target channel is then calculated as follows:

[0069] Time difference

[0070] In this embodiment, step S6 performs computational processing on each channel using OpenCL for parallel computation acceleration, including the following sub-steps:

[0071] Step S61: Calculate the data sampling rate of the combined signal based on the data sampling rate R of each channel;

[0072] Step S62: Upsample the data of each channel by an integer multiple, and perform interpolation filtering without extraction;

[0073] Step S63: Perform frequency mixing processing on the upsampled data of each channel, and complete the frequency mixing calculation by looking up the cos and sin values ​​in the memory table;

[0074] Step S64: Calculate the amplitude mean of the mixed data for each channel;

[0075] Step S65: Calculate the delay of each channel based on the precise phase time difference and correct the phase delay;

[0076] Step S66: Use addition to merge the sampling points of each channel.

[0077] In this embodiment, step S64, the mean amplitude calculation, further includes: recalculating the data amplitude values, using the first channel as a reference, and recalculating the data amplitude values ​​of the other channels.

[0078] The present invention also proposes a multi-channel nonlinear phase signal synthesis system, comprising:

[0079] The host computer module processes the data collected from each channel in real time based on the preprocessed parameters and sends instructions to the digital card module and the switch module.

[0080] Digital card module: Receives instructions from the host computer to control the underlying AD card and signal source, and reports the collected raw data to the host computer;

[0081] Switching module: Switches between the calibration signal source and the actual antenna receiving the real signal according to instructions;

[0082] Data processing module: Located in the host computer module, the GPU performs computational density processing, and the CPU performs logical processing.

[0083] In this embodiment, the sending of instructions from the host computer module includes: sending instructions to the digital card control signal source via PCIE or network to complete calibration preprocessing to obtain the time difference, frequency difference, and amplitude difference of each channel, and then sending instructions to switch the two-to-one switch to the actual antenna to receive the real signal.

[0084] In a preferred embodiment, multi-channel signal synthesis is as follows: Figure 1 The synthesis algorithm provided by this invention is implemented through the following steps:

[0085] Step 1: Control multiple channels to collect data in frequency order, and perform coarse time synchronization of the data after GPS / BD time synchronization;

[0086] Step 2: Control the two-way switch to switch the calibration signal source to send a signal to multiple channels simultaneously;

[0087] Step 3: Perform FFT calculations on the multi-channel acquired signals and find the maximum value to obtain the precise frequency offset of each channel. Then, combine this with the actual acquisition frequency of each channel to calculate the frequency position in the baseband of the synthesized signal (e.g., ...). Figure 3 The system has three channels, each with a bandwidth of 160MHz, for a total bandwidth of 480MHz. The signal frequency is 1000MHz, and the bandwidth is 400MHz. The calibrated center frequencies for the three channels are set to 840MHz+DH1, 1000MHz+DH2, and 1160MHz+DH3, respectively. After acquisition begins, three baseband data streams with a bandwidth of 160MHz are obtained, with an effective frequency range of -80MHz to 80MHz. After triple resampling, the data is mixed and frequency shifted at -320MHz, 0MHz, and 320MHz. Finally, the three data segments are added together to complete the merging process (DH is the frequency offset calculated using the calibrated signal source).

[0088] Step 4: Perform "correlation" calculations on the multiple acquired signals to obtain the precise time difference of each channel;

[0089] Step 5: Average the amplitudes of the multiple acquired signals to calculate the amplitude difference between each channel;

[0090] Step 6: Calculate the mixing cosine and sin phase-value table based on the frequency position of each channel in the synthesized baseband and write it into memory;

[0091] Step 7: Control the two-way switch to switch the antenna to receive the actual signal;

[0092] Step 8: Perform calculations on each channel based on the deviation values ​​obtained from preprocessing;

[0093] Step 9: Combine the processed data from each channel into a single signal.

[0094] In this process, the FFT of each channel is calculated as the SFT (Short Time Fourier Transform) with the same parameters, and the spectral data of each channel is obtained by the maximum hold. Since the signal source transmits a single-tone signal, the frequency deviation of each channel can be obtained by finding the maximum value.

[0095] By comparing the time codes in the data of each channel, the time of each channel can be initially synchronized, and then the precise phase difference of each channel can be obtained through relevant algorithms.

[0096] The process involves initially synchronizing the time of each channel by comparing the time codes in the data from each channel. Then, a correlation algorithm is used to obtain the precise phase difference between each channel. This phase difference, converted to time, becomes the precise time difference between the channels. Using the first channel as a reference channel, the phase difference between the remaining channels relative to the reference channel is calculated. Numerically, this is reflected in the maximum correlation value obtained at different offsets for different channel data. The basic correlation algorithm uses the sliding window Pearson correlation algorithm, the principle of which is as follows:

[0097] Let the sliding window size be n, and let x and y represent two different channel data sequences. Let the correlation be the value of the target channel data when the window slides to the k-th point. in s is the mean of the sampled signal points window. x s y x is the standard deviation. i y i γ is the i-th offset point relative to the starting position of the sliding window. k The value range is [-1, +1], let γ pq =max{γ k ,k=0,1,2,3…}|0.8≤γ k The optimal correlation point for the signal is p, where p is the position offset of the optimal alignment position relative to the starting data of the target channel, and q is the position offset of the sliding window of the reference channel relative to the starting data. The phase difference between the reference channel and the target channel can then be obtained. Time difference This phase / time difference will be used for subsequent correction. In practice, the reference channel usually takes a fixed window size of data and remains stationary, while only the target channel data window slides. If the optimal correlation position that meets the conditions is not found after sliding a sufficient length, the reference channel window slides backward a specified distance and is recalculated with the target channel data. The phase difference of the remaining channels is obtained by performing the above correlation calculation with different channels using the reference channel.

[0098] In step 8, OpenCL is used to accelerate the parallel processing of each channel. Figure 2 This diagram illustrates the data processing for each channel, and the specific steps can be described as follows:

[0099] Step a: Calculate the data sampling rate of the synthesized signal based on the data sampling rate R of each channel (considering that the sampling rates of each channel are the same, the sampling rate after synthesis is N*R, where N is the number of channels);

[0100] Step b: Upsample the data of each channel. The sampling multiple is an integer multiple. Only interpolation filtering is needed and no extraction is required.

[0101] Step c: Mix the upsampled data from each channel. The cosine and sinine values ​​can be quickly obtained by looking up the memory table to complete the mixing calculation.

[0102] Step d: Calculate the amplitude mean of the mixed data from each channel;

[0103] Step e: Calculate the delay of each channel based on the precise phase time difference and correct the phase delay;

[0104] Step f: Use addition to merge the sampling points of each channel.

[0105] Specifically, the data amplitude values ​​are recalculated by using the first channel as a benchmark to recalculate the data amplitude values ​​of the other channels (the proportion is calculated based on the average).

[0106] This embodiment mainly consists of two parts: a digital card and a host computer. The digital card mainly receives instructions from the host computer to control the underlying AD card and signal source, and reports the collected raw data to the host computer. Signal synthesis is mainly completed by the host computer. The host computer sends instructions to the digital card via PCIe or network to control the signal source to complete calibration preprocessing to obtain the time difference, frequency difference, and amplitude difference of each channel. Then, it sends instructions to switch the two-to-one switch to the actual antenna to receive the real signal. The host computer processes the collected data of each channel in real time according to the parameters obtained from the preprocessing. The GPU handles the density-level processing, while the CPU performs logic processing.

[0107] The following is a brief description of one implementation of this signal synthesis method, using a general-purpose three-channel radio digital receiver and a general-purpose PC as examples:

[0108] The receiver channel bandwidth is 160MHz, corresponding to a sampling rate of 204.8MSps. The three channels have a center frequency of 1000MHz and a bandwidth of 480MHz. The frequency ranges of the three channels are (840+df1):160, (1000+df2):160, and (1160+df3):160, respectively. Here, df1, df2, and df3 are the frequency deviations calculated by correlation of the three channels. The bandwidth of the three-channel composite is 480MHz, and the sampling rate is 204.8*3=614.4MSps. After the host computer receives the data reported by the three channels through PCIe, it performs upsampling by 3 times. The mixing positions of the three channels are determined in the range of -fs / 2 to fs / 2: -320MHz, 0MHz, and 320MHz. The three channels are mixed, the amplitude values ​​are recalculated, and then the three channels are added together to output the composite data.

[0109] This invention proposes a multi-signal combining method that does not rely on time interleaving and frequency division multiplexing algorithms of multiple ADCs, making it suitable for real-time ZC of large bandwidth signals at a lower cost. It uses GPS / BD to provide time synchronization to multiple acquired data channels and writes time codes, and calibrates and synchronizes the phase and amplitude between channels using a self-testing signal source structure correlation algorithm. Through fast mixing calculations using lookup tables, polyphase filtering, and OpenCL acceleration, the time required for mixing operations can be significantly reduced. Based on the obtained precise phase and amplitude differences, multi-signal synthesis is performed quickly and accurately.

[0110] For the foregoing embodiments, in order to simplify the description, they are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to this application.

[0111] The above embodiments describe the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Modifications and variations made by those skilled in the art without departing from the spirit and scope of the invention should be within the protection scope of the appended claims.

Claims

1. A method for synthesizing multi-channel nonlinear phase signals, characterized in that, Includes the following steps: Step S1: Control multiple channels to collect data in frequency order, and perform coarse time synchronization of the data after GPS / BD time synchronization; Step S2: Control the two-way switch to switch to the calibration signal source, and send a signal to multiple channels simultaneously; Step S3: Perform FFT calculation on the multi-channel acquired signals and find the maximum value to obtain the precise frequency offset of each channel. Then, combine the actual acquisition frequency of each channel to calculate the frequency position of the synthesized signal in the baseband. Step S4: Perform correlation calculations on the multi-channel acquired signals to obtain the precise time difference and amplitude difference of each channel; Step S5: Calculate the mixing cosine and sinine phase values ​​based on the frequency position of each channel in the synthesized baseband and write them into the memory table; then control the two-way switch to switch the antenna to receive the real signal. Step S6: Perform calculations on each channel based on the deviation value obtained from preprocessing, and merge the processed data from each channel into one signal.

2. The multi-channel nonlinear phase signal synthesis method as described in claim 1, characterized in that, The calculation of the frequency position in step S3 specifically includes: Step S31: Set the calibrated center frequency according to the bandwidth and signal frequency of each of the n channels; Step S32: Start data acquisition to obtain the effective frequency range of n baseband data streams; Step S33: After n times resampling, perform frequency mixing, shift the spectrum according to the preset frequency, and finally add the data to complete the merging.

3. The multi-channel nonlinear phase signal synthesis method as described in claim 1, characterized in that, Step S3 further includes: The spectrum data of each channel is obtained by performing a short-time four-factor transformation with the same parameters on the multi-channel acquired signals and holding the signal for maximum. The frequency deviation of each channel is obtained by finding the maximum value of the single-tone signal sent by the signal source. By comparing the time codes in the data of each channel, the time of each channel is initially synchronized, and then the precise phase difference of each channel is obtained through relevant algorithms.

4. The multi-channel nonlinear phase signal synthesis method as described in claim 3, characterized in that, The phase difference, after being converted into time, becomes the precise time difference of the channel. Taking the first channel as the reference channel, the phase difference of the other channels relative to the reference channel is calculated. The value is the maximum correlation value obtained by different channel data at different offsets.

5. The multi-channel nonlinear phase signal synthesis method as described in claim 4, characterized in that, The relevant algorithms specifically include: Let the size of the sliding window be... ,make and Representing two different channel data sequences, the window slides to the target channel data... The correlation at the point is: ； in and The mean value of the sampled signal points within the window. and Standard deviation, and The position relative to the start of the sliding window. Offset point, The value range is [-1, +1]; set up max{ }|0.8≤ This is the point of optimal signal correlation. The optimal alignment position is offset relative to the starting data position of the target channel. The phase difference between the reference channel and the target channel is obtained by offsetting the sliding window of the reference channel relative to the starting data. 。 6. The multi-channel nonlinear phase signal synthesis method as described in claim 1, characterized in that, Step S6 performs computational processing on each channel using OpenCL for parallel computation acceleration, and includes the following sub-steps: Step S61: Calculate the data sampling rate of the combined signal based on the data sampling rate R of each channel; Step S62: Upsample the data of each channel by an integer multiple, and perform interpolation filtering without extraction; Step S63: Perform frequency mixing processing on the upsampled data of each channel, and complete the frequency mixing calculation by looking up the cos and sin values ​​in the memory table; Step S64: Calculate the amplitude mean of the mixed data for each channel; Step S65: Calculate the delay of each channel based on the precise phase time difference and correct the phase delay; Step S66: Use addition to merge the sampling points of each channel.

7. The multi-channel nonlinear phase signal synthesis method as described in claim 6, characterized in that, The step S64 amplitude mean calculation also includes: recalculating the data amplitude values, using the first channel as a reference, and recalculating the data amplitude values ​​of the other channels.

8. A multi-channel nonlinear phase signal synthesis system, used to implement the multi-channel nonlinear phase signal synthesis method according to any one of claims 1 to 7, characterized in that, include: The host computer module processes the data collected from each channel in real time based on the preprocessed parameters and sends instructions to the digital card module and the switch module. Digital card module: Receives instructions from the host computer to control the underlying AD card and signal source, and reports the collected raw data to the host computer; Switching module: Switches between the calibration signal source and the actual antenna receiving the real signal according to instructions; Data processing module: Located in the host computer module, the GPU performs computational density processing, and the CPU performs logical processing.

9. A multi-channel nonlinear phase signal synthesis system as described in claim 8, characterized in that, The transmission of instructions from the host computer module includes: sending instructions to the digital card control signal source via PCIE or network to complete calibration preprocessing to obtain the time difference, frequency difference and amplitude difference of each channel, and then sending instructions to switch the two-to-one switch to the actual antenna to receive the real signal.

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