Multi-channel signal calibration system and method

Abstract

The embodiment of the invention provides a multichannel signal calibration system and method, and relates to the field of radar signal processing, a sum-difference device is used for receiving a test signal transmitted by a radar and processing the test signal into a plurality of paths of signals, a signal processing module is used for receiving the plurality of paths of signals and processing the plurality of paths of signals to obtain a plurality of processed first signals, and the plurality of processed first signals are used for calibrating the plurality of first signals. The PS end is used for receiving a plurality of first signals, calculating an alignment coefficient and sending the alignment coefficient to the PL end, the PL end is used for carrying out distance alignment on the first signals based on the alignment coefficient to obtain a plurality of paths of aligned signals and processing the plurality of paths of aligned signals to obtain a plurality of processed second signals, and the PS end is used for receiving the plurality of second signals and sending the plurality of second signals to the PL end. And amplitude-phase calibration is carried out on each second signal to obtain a plurality of calibrated target signals, so that the calibration precision can be improved.

Description

Technical Field

[0001] This invention relates to the field of radar signal processing, and more specifically, to a multi-channel signal calibration system and method. Background Technology

[0002] The existing method for calibrating multi-channel signals involves a hardware architecture primarily composed of a control console, a seeker head (containing radar), a target simulator, a laser alignment device, and a loudspeaker. The laser alignment device is mounted symmetrically above and to the left and right of the radar. The loudspeaker is positioned on the target simulator, with three small holes on its end face corresponding to the laser alignment device. When the light emitted by the three laser alignment devices simultaneously passes through these three holes, precise alignment between the radar and the target simulator is achieved. The technical process of this scheme is as follows: 1) Set the radar antenna inside the seeker head to an initial zero position (both azimuth and elevation angles are zero degrees), and precisely align the seeker head with the target simulator using the laser alignment device. 2) Select a calibration mode (including single-horizontal mode, single-vertical mode, and dual-polarization mode), and detect the amplitude and phase parameters of each radar channel in the corresponding mode. Specifically, each channel is detected individually by setting the calibration coefficient of the channel to be tested to "1" and the coefficients of the other channels to "0". 3) Compare the detected amplitude and phase parameters with preset thresholds (signal-to-noise ratio > 20, target phase within -180° to 180°). If qualified, store and upload to the control console. During the detection process, multiple frames of data are collected when one channel is open. The amplitude and phase parameters of the maximum amplitude point in each frame are stored. The amplitude and phase parameters of three consecutive frames are selected. If at least two of them are within the preset threshold range, the amplitude and phase parameters of that channel are considered valid. Then, the amplitude and phase parameters of one frame within the threshold range are selected for storage and upload. 4) Rotate the radar antenna to a preset angle and repeat steps 2-3 until the amplitude and phase parameters of all operating frequencies are detected and stored. This technical solution achieves automatic calibration by setting calibration coefficients through software, replacing the traditional manual calibration method. It is suitable for calibration and debugging of multi-frequency, large-scale radars.

[0003] Existing technologies only calibrate the amplitude and phase parameters of each channel, without considering the distance cell deviation caused by the time delay (nanosecond level) between channels. They focus only on amplitude and phase calibration, ignoring the signal consistency across the distance dimension. Furthermore, they employ a method of alternating single-channel activation (with the remaining channels deactivated), failing to account for the mutual interference when multiple channels operate simultaneously, leading to discrepancies between the calibration results and the actual scenario of three channels operating concurrently. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-channel signal calibration system and method that can improve the accuracy of multi-channel signal calibration.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a multi-channel signal calibration system, the system including a PL terminal, a PS terminal and a summator, the PL terminal including a signal processing module and a control module; The sum and difference device is used to receive the test signal transmitted by the radar and process the test signal into multiple signals; The signal processing module is used to receive multiple signals and process them to obtain multiple processed first signals. The PS terminal is used to receive multiple first signals, calculate the alignment coefficient, and send the alignment coefficient to the PL terminal; The PL terminal is used to perform distance alignment on each of the first signals based on the alignment coefficient to obtain aligned multi-channel signals, and to process the aligned multi-channel signals to obtain multiple processed second signals. The PS terminal is used to receive multiple second signals and perform amplitude and phase calibration on each of the second signals to obtain multiple calibrated target signals.

[0006] In an optional implementation, the signal processing module includes a pulse compression processing unit, an MTD processing unit, and a DMA processing unit. The pulse compression processing unit is used to perform pulse compression on each of the signals. The MTD processing unit is used to extract the Doppler signal from the pulse-compressed signal and extract the velocity spectrum of the Doppler signal through FFT operation to obtain multiple first signals. The DMA processing unit is used to send the multiple first signals to the PS terminal.

[0007] In an optional implementation, the PS terminal is specifically used to: determine a reference signal from each of the first signals; and, based on the reference signal, determine an alignment coefficient for each of the first signals other than the reference signal.

[0008] In an optional implementation, the plurality of first signals include a processed sum signal, a processed azimuth difference signal, and a processed pitch difference signal; The PS terminal is specifically used to determine the first receiving position of the processed sum signal, the second receiving position of the processed azimuth difference signal, and the third receiving position of the processed pitch difference signal. The farthest receiving position among the first receiving position, the second receiving position, and the third receiving position is used as the reference signal; The first distance unit value of the processed sum signal, the second distance unit value of the processed azimuth difference signal, and the third distance unit value of the processed pitch difference signal are determined respectively. When the processed sum signal is used as the reference signal, the first difference between the first distance unit value and the second distance unit value is used as the alignment coefficient of the processed azimuth difference signal. The second difference between the first distance unit value and the third distance unit value is used as the alignment coefficient of the processed pitch difference signal.

[0009] In an optional implementation, the control module includes a shiftram unit: The shiftram unit is used to receive the first difference and the second difference; The azimuth difference signal is delayed based on the first difference to perform distance alignment on the azimuth difference signal; The pitch difference signal is delayed based on the second difference to perform distance alignment on the pitch difference signal.

[0010] In an optional implementation, the PS terminal is specifically used for: Determine the amplitude of each of the second signals; Determine the minimum amplitude from the amplitudes corresponding to each of the second signals; The second signal corresponding to the minimum amplitude is used as the reference signal; Determine the reference phase and reference amplitude of the reference signal; Determine the first phase and first amplitude of the second signal other than the reference signal; For any second signal other than the reference signal, a calibration coefficient for the second signal is calculated based on the first phase, the first amplitude, the reference phase, and the reference amplitude.

[0011] In an optional implementation, the PS terminal is specifically used for: For any second signal other than the reference signal, calculate the ratio of the first amplitude to the reference amplitude; Calculate the third difference between the first phase and the reference phase; The ratio of the first amplitude to the reference amplitude and the third difference are used as the calibration coefficient of the second signal.

[0012] In an optional implementation, the PS terminal further includes a complex multiplication unit; The multiplication unit is used to receive the calibration coefficients of each of the second signals and perform amplitude and phase calibration on the second signals based on the calibration coefficients so that the amplitude and phase of each of the second signals are consistent.

[0013] In an optional implementation, the PL terminal is further configured to receive multiple target signals, process the multiple target signals to obtain multiple processed third signals, and send each of the third signals to the PS terminal; The PS terminal is also used to determine the second amplitude and second phase of each of the third signals; Determine the fourth difference between each of the second amplitudes; Determine the fifth difference between each of the second phases; The fourth difference is compared with a preset amplitude threshold. When the fourth difference is less than or equal to the preset amplitude threshold, the fifth difference is compared with the preset phase threshold; If the fifth difference is less than or equal to the preset phase threshold, then the calibration is determined to be successful.

[0014] Secondly, embodiments of this application provide a multi-channel signal calibration method, which calibrates multiple signals using a multi-channel signal calibration system.

[0015] This application has the following beneficial effects: This application uses a summer and differencer to receive test signals transmitted by radar and processes the test signals into multiple signals. A signal processing module receives the multiple signals and processes them to obtain multiple processed first signals. The PS terminal receives the multiple first signals, calculates the alignment coefficient, and sends the alignment coefficient to the PL terminal. The PL terminal performs range alignment on each first signal based on the alignment coefficient to obtain aligned multiple signals. It then processes the aligned multiple signals to obtain multiple processed second signals. The PS terminal receives the multiple second signals and performs amplitude and phase calibration on each second signal to obtain calibrated multiple target signals, thereby improving calibration accuracy. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A block diagram of an electronic device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a multi-channel signal calibration system provided in an embodiment of the present invention; Figure 3 This is one of the flowcharts illustrating a multi-channel signal calibration method provided in an embodiment of the present invention; Figure 4 This is a second schematic flowchart of a multi-channel signal calibration method provided in an embodiment of the present invention; Figure 5 This is the third flowchart illustrating a multi-channel signal calibration method provided in an embodiment of the present invention. Figure 6 This is the fourth flowchart illustrating a multi-channel signal calibration method provided in an embodiment of the present invention. Detailed Implementation

[0018] 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.

[0019] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0020] 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.

[0021] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0022] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0023] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] Extensive research by the inventors revealed that existing technologies only calibrate the amplitude and phase parameters of each channel, neglecting the distance unit deviation caused by the time delay (nanosecond level) between channels. They focus solely on amplitude and phase calibration, ignoring the signal consistency across the distance dimension. Furthermore, the use of a single-channel-in-phase approach (with other channels off) for calibration fails to account for the mutual interference when multiple channels operate simultaneously, leading to discrepancies between the calibration results and the actual scenario of three channels operating concurrently.

[0025] In view of the above-mentioned problems, this embodiment provides a multi-channel signal calibration system and method, which can receive test signals transmitted by radar through a summer and differencer, process the test signals into multiple signals, receive the multiple signals and process the multiple signals to obtain multiple processed first signals, receive the multiple first signals and perform range alignment on each first signal to obtain aligned multiple signals, process the aligned multiple signals on the PL terminal to obtain multiple processed second signals, and receive the multiple second signals and perform amplitude and phase calibration on each second signal to obtain multiple calibrated target signals, thereby improving calibration accuracy. The solution provided in this embodiment will be described in detail below.

[0026] This embodiment provides an electronic device capable of calibrating multi-channel signals.

[0027] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the electronic device 10 provided in an embodiment of this application. The electronic device 10 may further include... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown. Figure 1 The components shown can be implemented using hardware, software, or a combination thereof.

[0028] The electronic device 10 includes a multi-channel signal calibration device 110, a memory 120, and a processor 130.

[0029] The components of the memory 120 and processor 130 are electrically connected directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The multi-channel signal calibration device 110 includes at least one software function module that can be stored in the memory 120 in the form of software or firmware or embedded in the operating system (OS) of the electronic device 10. The processor 130 is used to execute executable modules stored in the memory 120, such as the software function modules and computer programs included in the multi-channel signal calibration device 110.

[0030] The memory 120 may be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory 120 is used to store programs, and the processor 130 executes the programs after receiving execution instructions.

[0031] Please refer to Figure 2 This is a schematic diagram of the structure of a multi-channel signal calibration system.

[0032] The multi-channel signal calibration system includes a PL terminal 100, a PS terminal 200, and a summer (not shown in the figure). The PL terminal 100 includes a signal processing module 101 and a control module 102. The summer is used to receive the test signal transmitted by the radar and process the test signal into multiple signals. The signal processing module 101 is used to receive the multiple signals and process them to obtain multiple processed first signals. The PS terminal 200 is used to receive the multiple first signals, calculate the alignment coefficient, and send the alignment coefficient to the PL terminal 100. The PL terminal 100 is used to perform range alignment on each first signal based on the alignment coefficient to obtain aligned multiple signals, and then processes the aligned multiple signals to obtain multiple processed second signals. The PS terminal 200 is used to receive the multiple second signals and perform amplitude and phase calibration on each second signal to obtain multiple calibrated target signals.

[0033] The PS and PL terminals exchange data with the PL terminal via the AXI bus.

[0034] The sum and difference receiver receives the test signal transmitted by the radar and processes the test signal into multiple signals. For example, the sum and difference receiver receives the test signal transmitted by the radar and generates three signals: the sum signal, the azimuth difference signal, and the elevation difference signal.

[0035] The signal processing module 101 includes a pulse compression processing unit 1011, an MTD processing unit 1012, and a DMA processing unit 1013. The pulse compression processing unit 1011 is used to perform pulse compression on each signal. The MTD processing unit 1012 is used to extract the Doppler signal from the pulse-compressed signal and extract the velocity spectrum of the Doppler signal through FFT operation to obtain multiple first signals. The DMA processing unit 1013 is used to send the multiple first signals to the PS terminal.

[0036] The pulse compression processing unit 1011 is used to compress the test signal transmitted by the radar to improve the range resolution. The MTD processing unit 1012 is used for moving target detection and suppressing clutter interference. The DMA processing unit 1013 is used to realize data transmission between the PL end and the PS end.

[0037] After the multiple signals are processed by the pulse compression processing unit 1011, the MTD processing unit 1012 and the DMA processing unit 1013 of the signal processing module, the processed multiple first signals are obtained, namely the processed sum signal, the processed azimuth difference signal and the processed elevation difference signal.

[0038] The DMA processing unit 1013 of the PL terminal 200 sends the processed first signals to the PS terminal 200. The PS terminal 200 calculates the alignment coefficient based on the received first signals and sends the alignment coefficient to the PL terminal 100. The PL terminal 100 performs range alignment based on the alignment coefficient and performs pulse compression and MTD processing on the range-aligned first signals to obtain multiple second signals. The DMA processing unit 1012 transmits the multiple second signals to the PS terminal 200. The PS terminal 200 performs amplitude and phase calibration on each second signal, thus completing the calibration of the test signal transmitted by the radar.

[0039] The alignment coefficient is the distance between signals from different channels. If the echo signal of channel 1 falls on the 5th point and the echo signal of channel 2 falls on the 8th point, then the alignment coefficient of channel 1 is 0 and the alignment coefficient of channel 2 is 3.

[0040] The PL end also includes a GP interface 1015, which is used to receive alignment coefficients sent by the PS end.

[0041] There are several ways to perform distance alignment on multiple first signals. In one implementation, such as... Figure 3 As shown, it includes the following steps: S201: The PS terminal determines the reference signal from each of the first signals.

[0042] S202: The PS terminal determines the alignment coefficient of each first signal other than the reference signal based on the reference signal.

[0043] S203: The PL terminal performs distance alignment on the first signal based on the alignment coefficient of the first signal to obtain the aligned multi-channel signal.

[0044] For example, the multiple first signals include a sum signal, an azimuth difference signal, and an elevation difference signal.

[0045] A reference signal is determined from the sum signal, azimuth difference signal, and pitch difference signal. If the sum signal is used as the reference signal, the alignment coefficients of the azimuth difference signal and the pitch difference signal relative to the sum signal are determined. If the azimuth difference signal is used as the reference signal, the alignment coefficients of the sum signal and the pitch difference signal relative to the azimuth difference signal are determined. If the pitch difference signal is used as the reference signal, the alignment coefficients of the sum signal and the azimuth difference signal relative to the pitch difference signal are determined. The alignment coefficients of the first signal (excluding the reference signal) are sent to the PL terminal. The PL terminal receives each alignment coefficient and aligns the first signal corresponding to the alignment coefficient with the reference signal.

[0046] There are several ways to determine the alignment coefficients of each first signal other than the reference signal based on the reference signal. In one implementation, such as... Figure 4 As shown, it includes the following steps: S301: Determine the first receiving position of the processed sum signal, the second receiving position of the processed azimuth difference signal, and the third receiving position of the processed pitch difference signal.

[0047] S302: Select the farthest receiving position from the first receiving position, the second receiving position, and the third receiving position, and use the first signal corresponding to the farthest receiving position as the reference signal.

[0048] S303: Determine the first distance unit value of the signal, the second distance unit value of the processed azimuth difference signal, and the third distance unit value of the processed pitch difference signal, respectively.

[0049] S304: When the processed sum signal is the reference signal, the first difference between the first distance unit value and the second distance unit value is used as the alignment coefficient of the processed azimuth difference signal.

[0050] S305: Use the second difference between the first distance unit value and the third distance unit value as the alignment coefficient of the processed pitch difference signal.

[0051] For example, the first receiving position of the sum signal after processing by the signal processing module is A1, the second receiving position of the azimuth difference signal after processing by the signal processing module is A2, and the third receiving position of the pitch difference signal after processing by the signal processing module is A3. The farthest receiving position is determined from A1, A2, and A3. For example, if A1 is the farthest receiving position, then the sum signal after processing by the signal processing module is used as the reference signal.

[0052] The first distance unit value N0 of the processed sum signal, the second distance unit value N1 of the processed azimuth difference signal, and the third distance unit value N2 of the processed pitch difference signal are determined respectively.

[0053] It should be noted that the first distance unit value of the processed sum signal is the distance unit value of the processed sum signal, the second distance unit value of the processed azimuth difference signal is the distance unit value of the processed azimuth difference signal, and the third distance unit value of the processed pitch difference signal is the distance unit value of the processed pitch difference signal.

[0054] In one example, if the reference signal is the processed sum signal, then the alignment coefficient of the azimuth difference signal is N0-N1, and the alignment coefficient of the pitch difference signal is N0-N2.

[0055] It should be noted that all alignment coefficients are non-negative integers.

[0056] like Figure 2 As shown, the PS terminal 200 sends the calculated alignment coefficients of the azimuth difference signal and the elevation difference signal to the shiftram unit 1014 of the PL terminal 100. The shiftram unit 1014 is used to delay the azimuth difference signal by N0-N1 sampling points based on N0-N1, and the shiftram unit 1014 is used to delay the elevation difference signal by N0-N2 sampling points based on N0-N2.

[0057] The PS terminal is used to receive multiple second signals and perform amplitude and phase calibration on each second signal to obtain multiple calibrated target signals. There are several ways to achieve this. In one implementation, such as... Figure 5 As shown, it includes the following steps: S401: Determine the amplitude of each second signal.

[0058] S402: Determine the minimum amplitude from the amplitudes corresponding to each second signal.

[0059] S403: Use the second signal corresponding to the minimum amplitude as the reference signal.

[0060] S404: Determines the reference phase and reference amplitude of the reference signal.

[0061] S405: Determine the first phase and first amplitude of a second signal other than the reference signal.

[0062] S406: For a second signal other than the reference signal, calculate the calibration coefficient of the second signal based on the first phase, the first amplitude, the reference phase, and the reference amplitude.

[0063] The PL terminal performs pulse compression and MTD processing on the three signals after distance alignment to obtain multiple second signals, and transmits the multiple second signals to the PS terminal via DMA. The PS terminal is used to perform amplitude and phase calibration on the multiple second signals.

[0064] The PS end performs amplitude and phase analysis on the received aligned second signal. The second signal with the smallest amplitude is selected as the reference signal, and a complex number 1 is generated as the calibration coefficient for this reference signal. The amplitude and phase differences between the other two second signals and the reference channel are calculated.

[0065] For example, if the amplitude of the reference signal is 0.8 times that of a certain calibrated signal and the phase difference is 20 degrees, then a complex number with a magnitude of 0.8 and a phase of -20 degrees is generated as the calibration coefficient of the calibrated signal.

[0066] Specifically, when the reference signal is a sum signal, the ratio of the first amplitude of the azimuth difference signal to the reference amplitude of the sum signal is calculated, and the third difference between the first phase of the azimuth difference signal and the reference phase of the sum signal is calculated, which serves as the calibration coefficient for the azimuth difference signal. The ratio of the first amplitude of the pitch difference signal to the reference amplitude of the sum signal is calculated, and the fourth difference between the first phase of the pitch difference signal and the reference phase of the sum signal is calculated, which serves as the calibration coefficient for the pitch difference signal.

[0067] like Figure 2 As shown, the calibration coefficients of the azimuth difference signal and the elevation difference signal are sent to the complex multiplication unit 201 of the PS terminal 200. The complex multiplication unit 201 of the PS terminal 200 performs complex multiplication operation on the calibrated signal and the corresponding amplitude and phase calibration coefficients to make the amplitude and phase of the calibrated signal consistent with the reference signal, thereby achieving amplitude and phase consistency of the three-channel signal.

[0068] Amplitude and phase calibration refers to amplifying or reducing the signal of each channel by using a multiplication unit to make the amplitude of each channel basically equal, and shifting the phase of each channel forward or backward to make the phase of each channel basically equal.

[0069] After each calibration of the test signal, the calibrated signal needs to be verified, such as... Figure 6 As shown, it includes the following steps: S501: The PL terminal receives multiple target signals, processes them to obtain multiple processed third signals, and sends each third signal to the PS terminal.

[0070] S502: Determine the second amplitude and second phase of each third signal.

[0071] S503: Determine the fourth difference between each of the second amplitudes.

[0072] S504: Determine the fifth difference between each second phase.

[0073] S505: Compare the fourth difference with the preset amplitude threshold.

[0074] S506: When the fourth difference is less than or equal to the preset amplitude threshold, the fifth difference is compared with the preset phase threshold.

[0075] S507: If the fifth difference is less than or equal to the preset phase threshold, the calibration is considered successful.

[0076] The PS end analyzes the received multiple third signals to determine whether the amplitude and phase differences of the multiple third signals meet the standards. If the fourth difference between each second amplitude is less than or equal to a preset amplitude threshold, and the fifth difference between each second phase is less than or equal to a preset phase threshold, then the calibration is considered successful. If the fourth difference between each second amplitude is greater than the preset amplitude threshold, or the fifth difference between each second phase is greater than the preset phase threshold, then the calibration is considered unsuccessful.

[0077] It should be noted that the preset amplitude threshold can be set to 0.5dB, 0.6dB, or 0.7dB, and the preset phase threshold can be set to 5°, 6°, or 7°, etc. This application embodiment does not impose specific limitations on these.

[0078] If the fourth difference between each second amplitude is greater than the preset amplitude threshold, or the fifth difference between each second phase is greater than the preset phase threshold, the system returns to the corresponding stage to recalculate the alignment coefficient or calibration coefficient and perform calibration. The number of calibration failures is then determined and compared with the preset number. If the number of calibration failures is greater than the preset number, a fault is marked and a system alarm is triggered.

[0079] It should be noted that the preset number of times can be set according to the actual situation, and this application embodiment does not impose specific restrictions on this.

[0080] This invention controls the relative delay of the three-channel signals to ≤1 sampling point (corresponding to a radar range resolution of ≤0.15m) through distance alignment, avoiding angle measurement errors caused by asynchronous distance measurement. Through amplitude and phase calibration, the amplitude difference of the three-channel signals is ≤0.3dB, and the phase difference is ≤3°, directly reducing the angle measurement error of the sum and difference three channels to ≤0.1°, far superior to the angle measurement accuracy of existing technologies. Signal alignment is achieved based on the range unit in the radar ranging function, allowing the calibration results to directly serve the core requirement of sum and difference three-channel angle measurement (signal comparison within the same range unit), solving the problem of existing technology calibration results being disconnected from the angle measurement scenario. Adopting a closed-loop process of "calibration-verification-retry," calibration deviations can be detected and corrected in a timely manner, ensuring that the three-channel signals maintain calibration accuracy over a long period under complex environments (such as temperature changes and equipment aging), making it more reliable than the single calibration of existing technologies. Based on the ZYNQ platform, hardware acceleration at the PL end (processing pulse compression, MTD, ShiftRAM, etc.) and software computation at the PS end work in tandem, with a single calibration time of ≤100ms, meeting the real-time operation requirements of radar. This represents a significant improvement in efficiency compared to the manual calibration and complex processes of existing technologies. Simultaneous processing and coordinated calibration of the three channels takes into account the mutual influence between channels, making the calibration results more consistent with the signal characteristics under actual operating conditions and avoiding the limitations of single-channel calibration in existing technologies.

[0081] This application also provides a multi-channel signal calibration method, which calibrates multiple signals using a multi-channel signal calibration system. This application also provides an electronic device 10, which includes a processor 130 and a memory 120. The memory 120 stores computer-executable instructions, which, when executed by the processor 130, implement the multi-channel signal calibration method.

[0082] This application embodiment also provides a computer-readable storage medium storing a computer program, which, when executed by a processor 130, implements the multi-channel signal calibration method.

[0083] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0084] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part. If the function is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0085] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0086] The above descriptions are merely various embodiments 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 technical scope 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 multi-channel signal calibration system, characterized in that, The system includes a PL terminal, a PS terminal, and a sum and difference device. The PL terminal includes a signal processing module and a control module. The sum and difference device is used to receive the test signal transmitted by the radar and process the test signal into multiple signals; The signal processing module is used to receive multiple signals and process them to obtain multiple processed first signals. The PS terminal is used to receive multiple first signals, calculate the alignment coefficient, and send the alignment coefficient to the PL terminal; The PL terminal is used to perform distance alignment on each of the first signals based on the alignment coefficient to obtain aligned multi-channel signals, and to process the aligned multi-channel signals to obtain multiple processed second signals. The PS terminal is used to receive multiple second signals and perform amplitude and phase calibration on each of the second signals to obtain multiple calibrated target signals.

2. The multi-channel signal calibration system according to claim 1, characterized in that, The signal processing module includes a pulse compression processing unit, an MTD processing unit, and a DMA processing unit. The pulse compression processing unit is used to perform pulse compression on each of the signals. The MTD processing unit is used to extract the Doppler signal from the pulse-compressed signal and extract the velocity spectrum of the Doppler signal through FFT operation to obtain multiple first signals. The DMA processing unit is used to send the multiple first signals to the PS terminal.

3. The multi-channel signal calibration system according to claim 1, characterized in that, The PS terminal is specifically used for: determining a reference signal from each of the first signals; and determining an alignment coefficient for each of the first signals other than the reference signal based on the reference signal.

4. The multi-channel signal calibration system according to claim 3, characterized in that, The plurality of first signals include the processed sum signal, the processed azimuth difference signal, and the processed pitch difference signal; The PS terminal is specifically used to determine the first receiving position of the processed sum signal, the second receiving position of the processed azimuth difference signal, and the third receiving position of the processed pitch difference signal. The farthest receiving position among the first receiving position, the second receiving position, and the third receiving position is used as the reference signal; The first distance unit value of the processed sum signal, the second distance unit value of the processed azimuth difference signal, and the third distance unit value of the processed pitch difference signal are determined respectively. When the processed sum signal is used as the reference signal, the first difference between the first distance unit value and the second distance unit value is used as the alignment coefficient of the processed azimuth difference signal. The second difference between the first distance unit value and the third distance unit value is used as the alignment coefficient of the processed pitch difference signal.

5. The multi-channel signal calibration system according to claim 4, characterized in that, The control module includes a shiftram unit: The shiftram unit is used to receive the first difference and the second difference; The azimuth difference signal is delayed based on the first difference to perform distance alignment on the azimuth difference signal; The pitch difference signal is delayed based on the second difference to perform distance alignment on the pitch difference signal.

6. The multi-channel signal calibration system according to claim 1, characterized in that, The PS terminal is specifically used for: Determine the amplitude of each of the second signals; Determine the minimum amplitude from the amplitudes corresponding to each of the second signals; The second signal corresponding to the minimum amplitude is used as the reference signal; Determine the reference phase and reference amplitude of the reference signal; Determine the first phase and first amplitude of the second signal other than the reference signal; For any second signal other than the reference signal, a calibration coefficient for the second signal is calculated based on the first phase, the first amplitude, the reference phase, and the reference amplitude.

7. The multi-channel signal calibration system according to claim 6, characterized in that, The PS terminal is specifically used for: For any second signal other than the reference signal, calculate the ratio of the first amplitude to the reference amplitude; Calculate the third difference between the first phase and the reference phase; The ratio of the first amplitude to the reference amplitude and the third difference are used as the calibration coefficient of the second signal.

8. The multi-channel signal calibration system according to claim 6, characterized in that, The PS terminal also includes a complex multiplication unit; The multiplication unit is used to receive the calibration coefficients of each of the second signals and perform amplitude and phase calibration on the second signals based on the calibration coefficients so that the amplitude and phase of each of the second signals are consistent.

9. The multi-channel signal calibration system according to claim 1, characterized in that, The PL terminal is also used to receive multiple target signals, process the multiple target signals to obtain multiple processed third signals, and send each of the third signals to the PS terminal; The PS terminal is also used to determine the second amplitude and second phase of each of the third signals; Determine the fourth difference between each of the second amplitudes; Determine the fifth difference between each of the second phases; The fourth difference is compared with a preset amplitude threshold. When the fourth difference is less than or equal to the preset amplitude threshold, the fifth difference is compared with the preset phase threshold; If the fifth difference is less than or equal to the preset phase threshold, then the calibration is determined to be successful.

10. A multi-channel signal calibration method, characterized in that, The multi-channel signal calibration system according to any one of claims 1-9 is used to calibrate multiple signals.

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