Millimeter wave phased array radar synchronization method

Abstract

The invention discloses a millimeter wave phased array radar synchronization method, relates to the field of phased array radar detection, solves the problem of low millimeter wave phased array radar detection accuracy, and comprises the following steps: sending a detection signal to a to-be-detected object, and capturing an echo signal returned from the to-be-detected object along the original path based on a phased array antenna; analyzing the echo signals to obtain time sequence deviations corresponding to different phased-array antennas, and performing time sequence synchronization on the phased-array antennas based on the time sequence deviations; analyzing a frequency error of the echo signal, calculating a frequency correction coefficient of the corresponding phased-array antenna based on the frequency error, and performing frequency synchronization; analyzing the phase error of the echo signal, and performing phase synchronization by combining the phase error; and the millimeter wave phased array radar completing the time sequence synchronization, the frequency synchronization and the phase synchronization executes a subsequently set exploration test, and the detection precision of the millimeter wave phased array radar is guaranteed by completing the time sequence synchronization, the frequency synchronization and the phase synchronization of the phased array antenna.

Description

Technical Field

[0001] This invention belongs to the field of phased array radar detection technology, specifically a synchronization method for millimeter-wave phased array radar. Background Technology

[0002] Millimeter-wave phased array radar is a radar system that uses the millimeter-wave frequency band and achieves beam scanning and direction control through phased array antenna technology. A phased array antenna consists of multiple radiating elements, each of which can independently adjust its signal phase to synthesize a beam in a specific direction. The phased array radar adjusts the phase of each radiating element so that the emitted electromagnetic waves form constructive interference in a specific direction, thus creating a beam pointing in that direction. During reception, the phase is similarly adjusted to focus the echo signal from that direction.

[0003] However, at present, the synchronization method of ordinary phased array radar is often used on millimeter-wave phased array radar. Since millimeter-wave phased array radar has higher accuracy, the traditional synchronization method is prone to errors, which in turn affects the final imaging of millimeter-wave phased array radar.

[0004] Therefore, this invention proposes a synchronization method for millimeter-wave phased array radar. Summary of the Invention

[0005] The purpose of this invention is to propose a synchronization method for millimeter-wave phased array radar to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A synchronization method for millimeter-wave phased array radar, the method comprising:

[0008] Step S1: Send a detection signal to the object under test and capture the echo signal returning from the object under test along the original path based on the phased array antenna;

[0009] Step S2: Analyze the echo signal received by the phased array antenna, obtain the timing deviation corresponding to different phased array antennas, and perform timing synchronization of the phased array antenna based on the timing deviation.

[0010] Step S3: Analyze the frequency error of the echo signal corresponding to the phased array antenna, calculate the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and perform frequency synchronization of the phased array antenna based on the frequency correction coefficient.

[0011] Step S4: Analyze the phase error of the echo signal corresponding to the phased array antenna, obtain the phase error correction formula of the corresponding phased array antenna based on the phase error, and perform phase synchronization.

[0012] Step S5: Mark the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as the synchronized radar, and perform the subsequent exploration test.

[0013] Further, step S1 includes the following sub-steps:

[0014] Step S11: A millimeter-wave frequency band is generated by combining a frequency source with a waveform generator, and then the signal is amplified by a transmitter to obtain the detection signal.

[0015] Step S12: Obtain the location of the object under test, send the detection signal to the location of the object under test, and after the detection signal comes into contact with the object under test, transmit the echo signal to the phased array antenna.

[0016] Step S13: The phased array antenna receives the echo signal, the phased array antenna is numbered i, and the echo signal is recorded as XHi according to the phased array antenna number; where i = 1, 2, ..., z, and z is a positive integer.

[0017] Further, step S2 includes the following sub-steps:

[0018] Step S21: Obtain the echo signals corresponding to multiple phased array antennas, and set the sampling interval of all phased array antennas to Ti = 1 / Fi, where Fi is the sampling frequency. Initially, the sampling interval of all phased array antennas is the same, T1 = T2 = ... = Tz;

[0019] Step S22, set the sampling time nodes of all phased array antennas as: CYn=n×Ti, where n is the number of the sampling time node, n=1,2,……,x, and x is a positive integer;

[0020] Step S23: Sample the echo signal received by the phased array antenna at the sampling time node and record the timestamp SJCin corresponding to each sampling operation; summarize the timestamps according to the sampling time node number to obtain the timestamp sequence corresponding to all phased array antennas.

[0021] Furthermore, step S2 also includes the following sub-steps:

[0022] Step S24: For any set of timestamp sequences, read the maximum and minimum values ​​in the timestamp sequences, and obtain the time series deviation value of the corresponding timestamp sequence by subtracting the minimum value from the maximum value; similarly, calculate the time series deviation value corresponding to all timestamp sequences.

[0023] Step S25: Sum all time series deviation values ​​and take the average to obtain the mean time series deviation. Calculate the standard deviation of the time series deviation based on the mean time series deviation and all time series deviation values. Compare the standard deviation of the time series deviation with the standard deviation threshold. If the standard deviation of the time series deviation is greater than or equal to the standard deviation threshold, proceed to the next step; if the standard deviation of the time series deviation is less than the standard deviation threshold, directly execute step S27.

[0024] Furthermore, step S2 also includes the following sub-steps:

[0025] Step S26: Record the timestamp of the first sampling time node and the timestamp of the last sampling time node corresponding to the phased array antenna. Subtract the timestamp of the first sampling time node from the timestamp of the last sampling time node, divide by the upper limit of the sampling time node number to obtain the sampling time interval of the corresponding phased array antenna and replace it.

[0026] Step S27: Record the timing deviation value corresponding to the first group of timestamp sequences, and compare the timing deviation value with the timing deviation threshold. If the timing deviation value is less than the timing deviation threshold, no operation is performed; if the timing deviation value is greater than or equal to the timing deviation threshold, adjust the actual sampling time of the first sampling time node corresponding to all phased array antennas to the maximum value of the corresponding timestamp sequence.

[0027] Furthermore, step S3 includes the following example steps:

[0028] Step S31: Obtain the actual detection frequency F0 corresponding to the detection signal;

[0029] Step S32: Obtain echo signals corresponding to multiple phased array antennas, convert the echo signals into digital signals corresponding to the echo signals through an analog-to-digital converter, and perform a fast Fourier transform on the digital signals to obtain frequency domain signals; wherein, the analog-to-digital converter is used to convert the received analog signals into digital signals;

[0030] Step S33: Divide the frequency of the phased array antenna by the length of the fast Fourier transform to obtain the frequency resolution PFi of the corresponding phased array antenna.

[0031] Step S34: Calculate the frequency corresponding to any sampling time node of the phased array antenna using the formula, which is as follows:

[0032] PLin = n × PFi.

[0033] Furthermore, step S3 also includes the following sub-steps:

[0034] Step S35: Traverse the frequencies of the corresponding sampling time nodes of the same phased array antenna, and identify the frequency peak of the corresponding phased array antenna as PLif;

[0035] Step S36: Subtract the actual detection frequency corresponding to the detection signal from the peak frequency of the phased array antenna and then take the absolute value to obtain the frequency error of the corresponding phased array antenna; and so on, calculate the frequency error corresponding to all phased array antennas.

[0036] Step S37: Compare the frequency error of all phased array antennas with the frequency error threshold. If the frequency error of the phased array antenna is greater than or equal to the frequency error threshold, then the corresponding phased array antenna is recorded as the frequency error antenna; if the frequency error of the phased array antenna is less than the frequency error threshold, then no operation is performed.

[0037] Furthermore, step S3 also includes the following sub-steps:

[0038] Step S38: Divide the frequency error corresponding to the frequency error antenna by the actual detection frequency corresponding to the detection signal to obtain the value of the frequency correction coefficient; compare the peak frequency corresponding to the frequency error antenna with the actual detection frequency corresponding to the detection signal. If the peak frequency corresponding to the frequency error antenna is greater than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is positive; if the peak frequency corresponding to the frequency error antenna is less than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is negative.

[0039] Step S39: The frequency of any sampling time node corresponding to the phased array antenna is multiplied by the frequency correction coefficient and replaced with the original frequency of the corresponding sampling time node to achieve frequency correction.

[0040] Furthermore, the process of the Fast Fourier Transform is as follows:

[0041] Step S321: Based on the phased array antenna echo signal obtained in steps S1 to S2, the sampled echo signal is defined as the sampled echo signal. The sampled echo signal is then passed through an ADC to obtain a digital signal; wherein, the digital signal is a set of discrete samples of real numbers.

[0042] Step S322: Define the digital signal as XH[n], and transform the digital signal XH[n] using a Discrete Fourier Transform (DFT) formula, as follows:

[0043] In the formula, e is the natural constant, and j is the imaginary unit. For complex exponential weights, FL[p] is a complex sequence, which is the frequency domain representation of the echo signal. Each corresponds to the complex amplitude of the echo signal at the p-th frequency component, p = 0, 1, ..., x-1.

[0044] Further, step S4 includes the following sub-steps:

[0045] Step S41: Obtain the frequency domain signal corresponding to the phased array antenna, and extract the main frequency component ZFi based on the frequency domain signal;

[0046] Step S42: Calculate the antenna phase φi corresponding to the main frequency component using the formula, as follows:

[0047] φi=arg(ZFi); where arg is a function for calculating the principal argument of a complex number, representing the angle between the complex number and the positive x-axis in the complex plane;

[0048] Step S43: Read the initial phase corresponding to the detection signal and record it as φ0; compare the initial phase corresponding to the detection signal with the antenna phase corresponding to the phased array antenna. If the initial phase corresponding to the detection signal is the same as the antenna phase corresponding to the phased array antenna, no operation is performed.

[0049] If the initial phase corresponding to the detection signal is different from the antenna phase corresponding to the phased array antenna, then proceed to step S44;

[0050] Step S44: Subtract the initial phase of the detection signal from the antenna phase corresponding to the phased array antenna to obtain the phase error Δφi of the corresponding phased array antenna; based on the phase error, obtain the phase error correction formula for the corresponding phased array antenna, as follows:

[0051] XZFi=ZFi×e -j×△φi In the formula, XZFi is the correction value of the corresponding main frequency component of the frequency domain signal;

[0052] Step S45: Replace the original frequency domain signal corresponding to the main frequency component with the correction value of the frequency domain signal corresponding to the main frequency component to complete the phase synchronization of the phased array antenna.

[0053] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0054] 1. This invention first sends a detection signal to the object under test and captures the echo signal returned from the object under test along the original path based on the phased array antenna; then, it analyzes the echo signal received by the phased array antenna, obtains the timing deviation corresponding to different phased array antennas, and performs timing synchronization of the phased array antenna based on the timing deviation; this invention achieves timing synchronization of the phased array antenna.

[0055] 2. This invention analyzes the frequency error of the echo signal corresponding to the phased array antenna, calculates the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and performs frequency synchronization of the phased array antenna based on the frequency correction coefficient; this invention achieves frequency synchronization of the phased array antenna.

[0056] 3. This invention analyzes the phase error of the echo signal corresponding to the phased array antenna, and obtains the phase error correction formula for the corresponding phased array antenna by combining the phase error and performs phase synchronization; finally, the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization and phase synchronization is recorded as the synchronized radar, and subsequent exploration tests are performed; this invention ensures the detection accuracy of millimeter-wave phased array radar by completing the timing synchronization, frequency synchronization and phase synchronization of the phased array antenna. Attached Figure Description

[0057] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0058] Figure 1 This is a flowchart of the method of the present invention;

[0059] Figure 2 This is a schematic diagram of the millimeter-wave phased array radar in this invention;

[0060] Figure 3 This is a schematic diagram of an electronic device involved in the present invention. Detailed Implementation

[0061] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] Example 1, please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a synchronization method for millimeter-wave phased array radar, which identifies the timing deviation, frequency error and phase error between multiple phased array antennas in millimeter-wave phased array radar, and corrects the antenna timing deviation, antenna frequency error and antenna phase error between different phased array antennas to achieve synchronization between multiple phased array antennas corresponding to the millimeter-wave phased array radar.

[0063] In this embodiment, the millimeter-wave phased array radar synchronization method is as follows:

[0064] Step S1: Send a detection signal to the object under test and capture the echo signal returning from the object under test along the original path based on the phased array antenna;

[0065] Step S1 in this invention includes the following sub-steps:

[0066] Step S11: A millimeter-wave frequency band is generated by combining a frequency source with a waveform generator, and then the signal is amplified by a transmitter to obtain the detection signal.

[0067] Step S12: Obtain the location of the object under test, send the detection signal to the location of the object under test, and after the detection signal comes into contact with the object under test, transmit the echo signal to the phased array antenna.

[0068] Step S13: The phased array antenna receives the echo signal, the phased array antenna is numbered i, and the echo signal is recorded as XHi according to the phased array antenna number; where i = 1, 2, ..., z, and z is a positive integer;

[0069] It should be noted that steps S1 and S2 are only used to determine the timing synchronization status of the phased array radar and make optimizations.

[0070] Step S2: Analyze the echo signal received by the phased array antenna, obtain the timing deviation corresponding to different phased array antennas, and perform timing synchronization of the phased array antenna based on the timing deviation.

[0071] In this invention, step S2 includes the following sub-steps:

[0072] Step S21: Obtain the echo signals corresponding to multiple phased array antennas, and set the sampling interval of all phased array antennas to Ti = 1 / Fi, where Fi is the sampling frequency (e.g., 1GHz). Initially, the sampling interval of all phased array antennas is the same, i.e., T1 = T2 = ... = Tz.

[0073] Step S22, set the sampling time nodes of all phased array antennas as: CYn=n×Ti, where n is the number of the sampling time node, n=1,2,……,x, and x is a positive integer;

[0074] Step S23: Sample the echo signal received by the phased array antenna at the sampling time node and record the timestamp SJCin corresponding to each sampling operation; summarize the timestamps according to the number of the sampling time node to obtain the timestamp sequence corresponding to all phased array antennas.

[0075] Step S24: For any set of timestamp sequences, read the maximum and minimum values ​​in the timestamp sequences, and obtain the time series deviation value of the corresponding timestamp sequence by subtracting the minimum value from the maximum value; similarly, calculate the time series deviation value corresponding to all timestamp sequences.

[0076] Step S25: Sum all time series deviation values ​​and take the average to obtain the mean time series deviation. Calculate the standard deviation of the time series deviation based on the mean time series deviation and all time series deviation values. Compare the standard deviation of the time series deviation to a standard deviation threshold. If the standard deviation of the time series deviation is greater than or equal to the standard deviation threshold, proceed to the next step; if the standard deviation of the time series deviation is less than the standard deviation threshold, directly execute step S27.

[0077] It needs to be explained in detail that if the standard deviation of the timing deviation is greater than or equal to the standard deviation threshold, it means that there is a delay in the sampling of the phased array antenna, and the sampling time interval needs to be adjusted to achieve sampling timing synchronization.

[0078] Step S26: Record the timestamp of the first sampling time node and the timestamp of the last sampling time node corresponding to the phased array antenna. Subtract the timestamp of the first sampling time node from the timestamp of the last sampling time node, divide by the upper limit of the sampling time node number to obtain the sampling time interval of the corresponding phased array antenna and replace it.

[0079] Step S27: Record the timing deviation value corresponding to the first group of timestamp sequences, and compare the timing deviation value with the timing deviation threshold. If the timing deviation value is less than the timing deviation threshold, no operation is performed; if the timing deviation value is greater than or equal to the timing deviation threshold, adjust the actual sampling time of the first sampling time node corresponding to all phased array antennas to the maximum value of the corresponding timestamp sequence.

[0080] For example, the timestamps of the first sampling time nodes for all phased array antennas are as follows: 1849855718040 (2028-08-14 16:48:38), 1849855722200 (2028-08-14 16:48:42), and 1849855725023 (2028-08-14 16:48:45). Then, the actual sampling time of the first sampling time node of all phased array antennas is adjusted to the maximum value of the timestamp sequence, i.e., 1849855725023.

[0081] The sampled echo signal is the amplitude value of the voltage or current at the corresponding moment.

[0082] It needs to be explained in detail that if the timing deviation value is greater than or equal to the timing deviation threshold, it means that the echo signals corresponding to different phased array antennas are not aligned at the sampling time, which leads to a deviation in the first sampling and causes errors in radar detection; for example, (the first sampling of the first group of phased array antennas is the first second of the echo signal, while the first sampling of the second group of phased array antennas is the third second of the echo signal).

[0083] Based on steps S1 and S2, the present invention assumes that multiple phased array antennas have been adjusted to a timing-synchronized state.

[0084] Step S3: Analyze the frequency error of the echo signal corresponding to the phased array antenna, calculate the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and perform frequency synchronization of the phased array antenna based on the frequency correction coefficient.

[0085] In this invention, step S3 includes the following sub-steps:

[0086] Step S31: Obtain the actual detection frequency F0 corresponding to the detection signal;

[0087] Step S32: Obtain echo signals corresponding to multiple phased array antennas, convert the echo signals into digital signals corresponding to the echo signals through an analog-to-digital converter, and perform a fast Fourier transform on the digital signals to obtain frequency domain signals; wherein, the analog-to-digital converter is used to convert the received analog signals into digital signals;

[0088] In this invention, the process of Fast Fourier Transform is as follows:

[0089] Step S321: Based on the phased array antenna echo signal obtained in steps S1 to S2, the sampled echo signal is defined as the sampled echo signal. The sampled echo signal is then passed through an ADC to obtain a digital signal; wherein, the digital signal is a set of discrete samples of real numbers.

[0090] Step S322: Define the digital signal as XH[n], and transform the digital signal XH[n] using a Discrete Fourier Transform (DFT) formula, as follows:

[0091] In the formula, e is the natural constant, j is the imaginary unit, and the square of j is -1. The complex exponential weight represents the weight of the nth sample on the p-th frequency component, with a magnitude of 1 and a phase of . FL[p] is a complex sequence that represents the echo signal in the frequency domain. Each number corresponds to the complex amplitude of the echo signal at the p-th frequency component, where p = 0, 1, ..., x-1.

[0092] Step S33: Divide the frequency of the phased array antenna by the length of the fast Fourier transform (x in this embodiment) to obtain the frequency resolution PFi of the corresponding phased array antenna.

[0093] Step S34: Calculate the frequency corresponding to any sampling time node of the phased array antenna using the formula, which is as follows:

[0094] PLin = n × PFi;

[0095] Step S35: Traverse the frequencies of the corresponding sampling time nodes of the same phased array antenna, and identify the frequency peak of the corresponding phased array antenna as PLif;

[0096] Step S36: Subtract the actual detection frequency corresponding to the detection signal from the peak frequency of the phased array antenna and then take the absolute value to obtain the frequency error of the corresponding phased array antenna; and so on, calculate the frequency error corresponding to all phased array antennas.

[0097] Step S37: Compare the frequency error of all phased array antennas with the frequency error threshold. If the frequency error of the phased array antenna is greater than or equal to the frequency error threshold, then the corresponding phased array antenna is recorded as the frequency error antenna; if the frequency error of the phased array antenna is less than the frequency error threshold, then no operation is performed.

[0098] Step S38: Divide the frequency error corresponding to the frequency error antenna by the actual detection frequency corresponding to the detection signal to obtain the value of the frequency correction coefficient; compare the peak frequency corresponding to the frequency error antenna with the actual detection frequency corresponding to the detection signal. If the peak frequency corresponding to the frequency error antenna is greater than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is positive; if the peak frequency corresponding to the frequency error antenna is less than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is negative.

[0099] It should be noted that there is no situation where the peak frequency corresponding to the frequency error antenna is the same as the actual detection frequency corresponding to the detection signal. If they are the same, it means that there is no frequency error.

[0100] Step S39: The frequency of any sampling time node corresponding to the phased array antenna is multiplied by the frequency correction coefficient and replaced with the original frequency of the corresponding sampling time node to achieve frequency correction.

[0101] Step S4: Analyze the phase error of the echo signal corresponding to the phased array antenna, obtain the phase error correction formula of the corresponding phased array antenna based on the phase error, and perform phase synchronization.

[0102] In this invention, step S4 includes the following sub-steps:

[0103] Step S41: Obtain the frequency domain signal corresponding to the phased array antenna, and extract the main frequency component ZFi based on the frequency domain signal;

[0104] Step S42: Calculate the antenna phase φi corresponding to the main frequency component using the formula, as follows:

[0105] φi=arg(ZFi); where arg is a function for calculating the principal argument of a complex number, representing the angle between the complex number and the positive x-axis in the complex plane;

[0106] Step S43: Read the initial phase corresponding to the detection signal and record it as φ0; compare the initial phase corresponding to the detection signal with the antenna phase corresponding to the phased array antenna. If the initial phase corresponding to the detection signal is the same as the antenna phase corresponding to the phased array antenna, no operation is performed.

[0107] If the initial phase corresponding to the detection signal is different from the antenna phase corresponding to the phased array antenna, then proceed to step S44;

[0108] Step S44: Subtract the initial phase of the detection signal from the antenna phase corresponding to the phased array antenna to obtain the phase error Δφi of the corresponding phased array antenna; based on the phase error, obtain the phase error correction formula for the corresponding phased array antenna, as follows:

[0109] XZFi=ZFi×e -j×△φi In the formula, XZFi is the correction value of the corresponding main frequency component of the frequency domain signal;

[0110] Step S45: Replace the original frequency domain signal corresponding to the main frequency component with the correction value of the frequency domain signal corresponding to the main frequency component to complete the phase synchronization of the phased array antenna.

[0111] Step S5: Mark the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as the synchronized radar, and perform the subsequent exploration test.

[0112] Example 2, as Figure 3 As shown, this embodiment provides an electronic device that may include a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus. The processor can call logic instructions in memory to execute a millimeter-wave phased array radar synchronization method. This method includes: sending a detection signal to the object under test and capturing the echo signal returning from the object via the original path using a phased array antenna; analyzing the echo signal received by the phased array antenna to obtain the timing deviation corresponding to different phased array antennas, and synchronizing the phased array antennas based on the timing deviation; analyzing the frequency error of the echo signal corresponding to the phased array antenna, calculating the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and synchronizing the frequency of the phased array antenna based on the frequency correction coefficient; analyzing the phase error of the echo signal corresponding to the phased array antenna, obtaining the phase error correction formula for the corresponding phased array antenna based on the phase error, and synchronizing the phase; and marking the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as a synchronized radar, and executing subsequent exploration tests.

[0113] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and 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 a 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 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.

[0114] On the other hand, this application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by the computer, the computer can execute a millimeter-wave phased array radar synchronization method provided by the above methods. The method includes: sending a detection signal to the object under test and capturing the echo signal returned from the object under test along the original path based on the phased array antenna; analyzing the echo signal received by the phased array antenna, analyzing the timing deviation corresponding to different phased array antennas, and synchronizing the phased array antennas based on the timing deviation; analyzing the frequency error of the echo signal corresponding to the phased array antenna, calculating the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and synchronizing the frequency of the phased array antenna based on the frequency correction coefficient; analyzing the phase error of the echo signal corresponding to the phased array antenna, obtaining the phase error correction formula of the corresponding phased array antenna based on the phase error, and synchronizing the phase; and recording the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as a synchronized radar, and performing subsequent exploration tests.

[0115] Furthermore, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the aforementioned millimeter-wave phased array radar synchronization method. This method includes: sending a detection signal to a target object and capturing the echo signal returned from the target object via a phased array antenna; analyzing the echo signal received by the phased array antenna to obtain timing deviations corresponding to different phased array antennas, and synchronizing the phased array antennas based on the timing deviations; analyzing the frequency error of the echo signal corresponding to the phased array antenna, calculating the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and synchronizing the frequency of the phased array antenna based on the frequency correction coefficient; analyzing the phase error of the echo signal corresponding to the phased array antenna, obtaining a phase error correction formula for the corresponding phased array antenna based on the phase error, and synchronizing the phase; and recording the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as a synchronized radar, and performing subsequent exploration tests.

[0116] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0117] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A synchronization method for millimeter-wave phased array radar, characterized in that, The methods include: Step S1: Send a detection signal to the object under test and capture the echo signal returning from the object under test along the original path based on the phased array antenna; Step S2: Analyze the echo signal received by the phased array antenna, obtain the timing deviation corresponding to different phased array antennas, and perform timing synchronization of the phased array antenna based on the timing deviation. Step S3: Analyze the frequency error of the echo signal corresponding to the phased array antenna, calculate the frequency correction coefficient of the corresponding phased array antenna based on the frequency error, and perform frequency synchronization of the phased array antenna based on the frequency correction coefficient. Step S4: Analyze the phase error of the echo signal corresponding to the phased array antenna, obtain the phase error correction formula of the corresponding phased array antenna based on the phase error, and perform phase synchronization. Step S5: Mark the millimeter-wave phased array radar that has completed timing synchronization, frequency synchronization, and phase synchronization as the synchronized radar, and perform the subsequent exploration test.

2. The millimeter-wave phased array radar synchronization method according to claim 1, characterized in that, Step S1 includes the following sub-steps: Step S11: A millimeter-wave frequency band is generated by combining a frequency source with a waveform generator, and then the signal is amplified by a transmitter to obtain the detection signal. Step S12: Obtain the location of the object under test, send the detection signal to the location of the object under test, and after the detection signal comes into contact with the object under test, transmit the echo signal to the phased array antenna. Step S13: The phased array antenna receives the echo signal, the phased array antenna is numbered i, and the echo signal is recorded as XHi according to the phased array antenna number; where i = 1, 2, ..., z, and z is a positive integer.

3. The millimeter-wave phased array radar synchronization method according to claim 1, characterized in that, Step S2 includes the following sub-steps: Step S21: Obtain the echo signals corresponding to multiple phased array antennas, and set the sampling interval of all phased array antennas to Ti = 1 / Fi, where Fi is the sampling frequency. Initially, the sampling interval of all phased array antennas is the same, T1 = T2 = ... = Tz; Step S22, set the sampling time nodes of all phased array antennas as: CYn=n×Ti, where n is the number of the sampling time node, n=1,2,……,x, and x is a positive integer; Step S23: Sample the echo signal received by the phased array antenna at the sampling time node and record the timestamp SJCin corresponding to each sampling operation; summarize the timestamps according to the sampling time node number to obtain the timestamp sequence corresponding to all phased array antennas.

4. The millimeter-wave phased array radar synchronization method according to claim 3, characterized in that, Step S2 further includes the following sub-steps: Step S24: For any set of timestamp sequences, read the maximum and minimum values ​​in the timestamp sequences, and obtain the time series deviation value of the corresponding timestamp sequence by subtracting the minimum value from the maximum value of the timestamp sequence. Similarly, calculate the timing deviation value corresponding to all timestamp sequences; Step S25: Sum all time series deviation values ​​and take the average to obtain the mean time series deviation. Calculate the standard deviation of the time series deviation based on the mean time series deviation and all time series deviation values. Compare the standard deviation of the time series deviation with the standard deviation threshold. If the standard deviation of the time series deviation is greater than or equal to the standard deviation threshold, proceed to the next step; if the standard deviation of the time series deviation is less than the standard deviation threshold, directly execute step S27.

5. The millimeter-wave phased array radar synchronization method according to claim 4, characterized in that, Step S2 further includes the following sub-steps: Step S26: Record the timestamp of the first sampling time node and the timestamp of the last sampling time node corresponding to the phased array antenna. Subtract the timestamp of the first sampling time node from the timestamp of the last sampling time node, divide by the upper limit of the sampling time node number to obtain the sampling time interval of the corresponding phased array antenna and replace it. Step S27: Record the timing deviation value corresponding to the first group of timestamp sequences, and compare the timing deviation value with the timing deviation threshold. If the timing deviation value is less than the timing deviation threshold, no operation is performed; if the timing deviation value is greater than or equal to the timing deviation threshold, adjust the actual sampling time of the first sampling time node corresponding to all phased array antennas to the maximum value of the corresponding timestamp sequence.

6. The millimeter-wave phased array radar synchronization method according to claim 1, characterized in that, Step S3 includes the following example steps: Step S31: Obtain the actual detection frequency F0 corresponding to the detection signal; Step S32: Obtain echo signals corresponding to multiple phased array antennas, convert the echo signals into digital signals corresponding to the echo signals through an analog-to-digital converter, and perform a fast Fourier transform on the digital signals to obtain frequency domain signals; wherein, the analog-to-digital converter is used to convert the received analog signals into digital signals; Step S33: Divide the frequency of the phased array antenna by the length of the fast Fourier transform to obtain the frequency resolution PFi of the corresponding phased array antenna. Step S34: Calculate the frequency corresponding to any sampling time node of the phased array antenna using the formula, which is as follows: PLin = n × PFi.

7. The millimeter-wave phased array radar synchronization method according to claim 6, characterized in that, Step S3 further includes the following sub-steps: Step S35: Traverse the frequencies of the corresponding sampling time nodes of the same phased array antenna, and identify the frequency peak of the corresponding phased array antenna as PLif; Step S36: Subtract the actual detection frequency corresponding to the detection signal from the peak frequency of the phased array antenna and then take the absolute value to obtain the frequency error of the corresponding phased array antenna; and so on, calculate the frequency error corresponding to all phased array antennas. Step S37: Compare the frequency error of all phased array antennas with the frequency error threshold. If the frequency error of the phased array antenna is greater than or equal to the frequency error threshold, then the corresponding phased array antenna is recorded as the frequency error antenna. If the frequency error of the phased array antenna is less than the frequency error threshold, no operation will be performed.

8. The millimeter-wave phased array radar synchronization method according to claim 7, characterized in that, Step S3 further includes the following sub-steps: Step S38: Divide the frequency error corresponding to the frequency error antenna by the actual detection frequency corresponding to the detection signal to obtain the value of the frequency correction coefficient; compare the peak frequency corresponding to the frequency error antenna with the actual detection frequency corresponding to the detection signal. If the peak frequency corresponding to the frequency error antenna is greater than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is positive; if the peak frequency corresponding to the frequency error antenna is less than the actual detection frequency corresponding to the detection signal, the sign of the frequency correction coefficient is negative. Step S39: The frequency of any sampling time node corresponding to the phased array antenna is multiplied by the frequency correction coefficient and replaced with the original frequency of the corresponding sampling time node to achieve frequency correction.

9. A millimeter-wave phased array radar synchronization method according to claim 6, characterized in that, The process of the Fast Fourier Transform is as follows: Step S321: Based on the phased array antenna echo signal obtained in steps S1 to S2, the sampled echo signal is defined as the sampled echo signal. The sampled echo signal is then passed through an ADC to obtain a digital signal; wherein, the digital signal is a set of discrete samples of real numbers. Step S322: Define the digital signal as XH[n], and transform the digital signal XH[n] using a Discrete Fourier Transform (DFT) formula, as follows: In the formula, e is the natural constant, and j is the imaginary unit. For complex exponential weights, FL[p] is a complex sequence, which is the frequency domain representation of the echo signal. Each corresponds to the complex amplitude of the echo signal at the p-th frequency component, p = 0, 1, ..., x-1.

10. The millimeter-wave phased array radar synchronization method according to claim 1, characterized in that, Step S4 includes the following sub-steps: Step S41: Obtain the frequency domain signal corresponding to the phased array antenna, and extract the main frequency component ZFi based on the frequency domain signal; Step S42: Calculate the antenna phase φi corresponding to the main frequency component using the formula, as follows: φi=arg(ZFi); where arg is a function for calculating the principal argument of a complex number, representing the angle between the complex number and the positive x-axis in the complex plane; Step S43: Read the initial phase corresponding to the detection signal and record it as φ0; compare the initial phase corresponding to the detection signal with the antenna phase corresponding to the phased array antenna. If the initial phase corresponding to the detection signal is the same as the antenna phase corresponding to the phased array antenna, no operation is performed. If the initial phase corresponding to the detection signal is different from the antenna phase corresponding to the phased array antenna, then proceed to step S44; Step S44: Subtract the initial phase of the detection signal from the antenna phase corresponding to the phased array antenna to obtain the phase error Δφi of the corresponding phased array antenna; based on the phase error, obtain the phase error correction formula for the corresponding phased array antenna, as follows: XZFi=ZFi×e -j×△φi In the formula, XZFi is the correction value of the corresponding main frequency component of the frequency domain signal; Step S45: Replace the original frequency domain signal corresponding to the main frequency component with the correction value of the frequency domain signal corresponding to the main frequency component to complete the phase synchronization of the phased array antenna.

Images