Array channel correction method for millimeter wave radar

Abstract

The application relates to the technical field of millimeter wave radars, and discloses an array channel correction method of a millimeter wave radar, which solves the problem of high cost of array channel correction of an existing millimeter wave radar, and mainly comprises the following steps: obtaining radar echo data of each receiving channel of a to-be-corrected array antenna under multiple rotation angles, and extracting measurement phase values of each receiving channel under each rotation angle according to the radar echo data; for each measurement phase value, a corresponding reference antenna is selected, and the reference antenna is dephased to obtain a target measurement phase value; the target measurement phase values of all rotation angles under each receiving channel are traversed, and the target measurement phase values corresponding to the rotation angles of phase value outliers are removed; theoretical phase values of each receiving channel under each rotation angle are calculated, and phase correction values of each receiving channel are determined according to the theoretical phase values and the target measurement phase values; and the spectrum data of each receiving channel are phase-corrected according to the phase correction values. The application reduces the phase correction cost.

Description

Technical Field

[0001] This invention relates to the field of millimeter-wave radar technology, and more specifically to a method for correcting the array channels of a millimeter-wave radar. Background Technology

[0002] With the development of millimeter-wave devices, high-speed digital signal processors, and LFMCW (linear frequency modulated continuous wave) radar signal processing technology, millimeter-wave radar applications in indoor personnel detection scenarios are becoming increasingly widespread. As the population ages, a pressing issue is the health and safety monitoring of elderly people living alone. Millimeter-wave radar can detect and obtain the distance, azimuth, elevation, and velocity information of the elderly in real time without disclosing any personal privacy. Simultaneously, it can autonomously classify and identify the elderly's activity status, such as walking, standing, sitting, and sleeping, especially with fall detection, sending timely alarms after a fall. Because the aforementioned personnel positioning and status detection rely on CBF (Conventional Beamforming) or MVDR (Minimum Variance Distortionless Response) processing of multi-channel spectral data to obtain azimuth and elevation angle measurements, the performance of millimeter-wave radar in indoor applications is significantly affected by angular measurement errors.

[0003] The actual receiving antennas used differ from the theoretical design values, being non-ideal linear devices. Antenna manufacturing errors affect the gain, phase delay, and microstrip patch antenna position of each receiving antenna. This is especially true for millimeter-wave radars, which operate at high frequencies and short wavelengths. Even minor differences in array components, machining errors, and assembly errors can lead to significant differences in the initial phase of each receiving antenna channel. This amplitude-phase difference causes channel mismatch, severely impacting the angle measurement results of CBF or MVDR, resulting in significant deviations in the obtained azimuth and elevation angle information of personnel targets, and consequently severely degrading the indoor personnel positioning and tracking performance of millimeter-wave radars. Furthermore, existing millimeter-wave radar array channel calibration requires an anechoic environment, which is costly. Summary of the Invention

[0004] This invention aims to solve the problem of high cost in the array channel correction of existing millimeter-wave radars, and proposes an array channel correction method for millimeter-wave radars.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0006] The array channel correction method for millimeter-wave radar includes the following steps:

[0007] Step 1: Place the array antenna to be calibrated on a servo turntable at a preset height, and set a corner reflector at a preset distance from the array antenna to be calibrated. The corner reflector is at the same height as the array antenna to be calibrated.

[0008] Step 2: Obtain radar echo data of each receiving channel of the antenna array to be calibrated at multiple rotation angles, and extract the measured phase value of the corner reflector echo of each receiving channel at each rotation angle based on the radar echo data.

[0009] Step 3: For each measured phase value, select the corresponding reference antenna, and perform phase ambiguity removal to obtain the target measured phase value of each receiving channel at each rotation angle;

[0010] Step 4: Traverse all target measurement phase values ​​for rotation angles under each receiving channel, and remove the target measurement phase values ​​for rotation angles corresponding to phase value outliers;

[0011] Step 5: Calculate the theoretical phase value of each receiving channel at each rotation angle, and determine the phase correction value of each receiving channel based on the theoretical phase value and the target measured phase value;

[0012] Step 6: After performing phase correction on the spectrum data of each receiving channel according to the phase correction value, input the data into the beamformer.

[0013] Furthermore, the radar echo data is a digital point-frequency signal after delinear frequency modulation.

[0014] Furthermore, the preset height is greater than the preset distance, the preset distance is greater than the far-field test distance, and the size of the corner reflector is smaller than the range resolution of the millimeter-wave radar.

[0015] Further, in step 2, the method for extracting the measured phase value includes:

[0016] Step 21: Perform windowed Fourier transform on the radar echo data of each receiving channel at each rotation angle to obtain the spectrum data corresponding to each distance.

[0017] Step 22: Determine the range cell number where the corner reflector is located, and extract the spectrum data corresponding to the range cell number. Based on this spectrum data, obtain the measured phase value of the corner reflector echo. The specific formula is as follows:

[0018]

[0019] in, To measure the phase value, arctan is the arctangent function, imag() is the imaginary part of the spectrum data, and real() is the real part of the spectrum data.

[0020] Furthermore, step 3 specifically includes:

[0021] Step 31: Determine the horizontal transmission angle of the array antenna to be calibrated at each rotation angle, and perform the following steps for each horizontal transmission angle:

[0022] Step 311: Using the i-th receiving channel as a reference channel, calculate the phase difference between the i-th receiving channel and the (i+1)-th receiving channel;

[0023] Step 312, if θ j <0, and but If θ j >0, and but

[0024] Where, θ j Let j be the j-th horizontal launch angle, where j = 1, 2, 3, ..., m, and m is the number of rotation angles. The measured phase value of the j-th horizontal transmission angle of the i-th receiving channel. The measured phase value of the j-th horizontal transmission angle of the (i+1)-th receiving channel The difference, i.e. i = 1, 2, 3, ..., n, where n is the number of receiving channels;

[0025] Step 313: Calculate the phase difference between each receiving channel and the first receiving channel to obtain the target measurement phase value of each receiving channel, i.e. The target measurement phase value at the j-th horizontal transmission angle of the i-th receiving channel.

[0026] Furthermore, step 4 specifically includes:

[0027] If the target measurement phase value If the following conditions are met, then Remove:

[0028] and

[0029] in, For the target phase value measured at the j-th horizontal transmission angle of the i-th receiving channel, For the target phase value measured at the (j-1)th horizontal transmission angle of the i-th receiving channel, The target phase value is measured for the (j+1)th horizontal transmission angle of the i-th receiving channel.

[0030] Furthermore, in step 5, the formula for calculating the theoretical phase value is as follows:

[0031]

[0032] in, The theoretical phase value of the j-th horizontal transmission angle of the i-th receiving channel, where λ is the wavelength, d is the channel spacing of the uniform linear array antenna, and θ j Let sin(θ) be the horizontal transmission angle of the array antenna to be corrected at each rotation angle. j )≈θ j .

[0033] Further, in step 5, the method for determining the phase correction value of each receiving channel includes:

[0034] Step 51: Calculate the difference between the measured phase value of the target and the corresponding theoretical phase value to obtain the residual error of each receiving channel at each rotation angle, i.e.:

[0035]

[0036] Among them, e i,j The remaining error for the j-th horizontal transmission angle of the i-th receiving channel;

[0037] Step 52: Normalize the remaining error, that is:

[0038]

[0039] Step 52: For each receiving channel, calculate the average value of the normalized error remaining after all rotation angles and take the conjugate to obtain the phase correction value of the corresponding receiving channel. The calculation formula is as follows:

[0040]

[0041] in, Let e ​​be the phase correction value for the i-th receiving channel. i ′ ,j The remaining error after normalization of the j-th horizontal transmission angle of the i-th receiving channel.

[0042] Furthermore, in step 6, the calculation formula for the phase correction is as follows:

[0043]

[0044] Among them, X i ′ represents the phase-corrected spectral data, X i The spectral data before phase correction. This is the phase correction value for the i-th receiving channel.

[0045] Furthermore, in step 6, the beamformer is a CBF or an MVDR;

[0046] The CBF measures the angle based on the following formula:

[0047]

[0048] The MVDR measures angles based on the following formula:

[0049]

[0050] in, y K For the measurement results, X i ′ represents the phase-corrected spectral data, a i Let i be the array steering vector for the i-th receiving channel. For a i The conjugate of θ K is the Kth scanning azimuth angle within the airspace, and n is the number of receiving channels;

[0051] Take the measurement result y K The angle θ corresponding to the maximum value in K As an angle measurement value θ′:

[0052]

[0053] The beneficial effects of the present invention are as follows: Compared with the existing millimeter-wave channel calibration methods, the array channel calibration method of the present invention can complete the calibration without an anechoic chamber environment, achieve clutter suppression, improve the direction finding accuracy, positioning accuracy and status detection accuracy of millimeter-wave radar, and has a lower cost and is easy to implement in batches in engineering. Attached Figure Description

[0054] Figure 1 This is a flowchart illustrating the array channel correction method for millimeter-wave radar according to an embodiment of the present invention.

[0055] Figure 2 This is a schematic diagram of the test scenario described in an embodiment of the present invention;

[0056] Figure 3 This is a schematic diagram of the target measurement phase values ​​of each receiving channel under different horizontal transmission angles according to an embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of the target measured phase values ​​of each receiving channel at different horizontal transmission angles after removing phase outliers, as described in an embodiment of the present invention.

[0058] Figure 5 This is a schematic diagram illustrating the angle measurement accuracy of CBF and MVDR before and after phase correction according to an embodiment of the present invention. Detailed Implementation

[0059] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0060] The millimeter-wave radar array channel correction method provided by this invention mainly includes the following technical solutions: Step 1: Place the array antenna to be corrected on a servo turntable at a preset height, and set a corner reflector at a preset distance from the array antenna to be corrected, wherein the corner reflector and the array antenna to be corrected have the same height; Step 2: Obtain radar echo data of each receiving channel of the array antenna to be corrected at multiple rotation angles, and extract the measured phase value of the corner reflector echo of each receiving channel at each rotation angle based on the radar echo data; Step 3: For each measured phase value, select the corresponding reference antenna, and perform phase de-ambiguation on it to obtain the target measured phase value of each receiving channel at each rotation angle; Step 4: Traverse the target measured phase values ​​of all rotation angles under each receiving channel, and remove the target measured phase values ​​of the rotation angle corresponding to the phase outliers; Step 5: Calculate the theoretical phase value of each receiving channel at each rotation angle, and determine the phase correction value of each receiving channel based on the theoretical phase value and the target measured phase value; Step 6: Perform phase correction on the spectrum data of each receiving channel based on the phase correction value and input it into the beamformer.

[0061] Specifically, this invention first sets up a servo turntable and a corner reflector in an open outdoor area, and places the array antenna to be calibrated on the servo turntable. The array antenna and the corner reflector have the same preset height and the horizontal distance between them is a preset distance. The center of the corner reflector is aligned with the phase center of the array antenna to be calibrated. Then, the servo turntable is controlled to rotate at multiple rotation angles, while acquiring radar echo data of each receiving channel of the array antenna to be calibrated at multiple rotation angles, and the measured phase value is extracted from the radar echo data. Next, the phase ambiguity of each measured phase value is resolved to obtain the corresponding target measured phase value, and phase outliers affected by clutter are removed. Finally, the phase difference between the obtained measured phase value and the calculated theoretical phase value is used to perform phase correction on each receiving channel to achieve clutter suppression, thereby improving the direction finding accuracy, positioning accuracy, and status detection accuracy of millimeter-wave radar.

[0062] Example

[0063] The array channel correction method for millimeter-wave radar described in this embodiment of the invention, such as... Figure 1 As shown, it includes the following steps:

[0064] Step 1: Place the array antenna to be calibrated on a servo turntable at a preset height, and set a corner reflector at a preset distance from the array antenna to be calibrated. The corner reflector is at the same height as the array antenna to be calibrated.

[0065] like Figure 2 As shown, in this embodiment, a servo turntable and a corner reflector are first set up in an open outdoor area, and the array antenna to be calibrated is placed on the servo turntable. The array antenna to be calibrated and the corner reflector have the same preset height and the horizontal distance between them is a preset distance. The center of the corner reflector is aligned with the phase center of the array antenna to be calibrated.

[0066] In order to minimize the impact of clutter on the radar echo of the diagonal reflector in the range dimension, in this embodiment, the preset height is greater than the preset distance, and the preset distance is greater than the far-field test distance. For example, the preset height is 1.5m, the preset distance is 1.2m, and the aperture of the array antenna to be calibrated is 40mm, which meets the far-field test conditions.

[0067] The size of the corner reflector is smaller than the range resolution of the millimeter-wave radar. In this embodiment, the range resolution of the millimeter-wave radar is 9 cm. The array antenna to be calibrated may include multiple transmitting antennas and multiple receiving antennas. In this embodiment, it includes 2 transmitting antennas and 4 receiving antennas, forming a uniform linear array in the azimuth dimension. The theoretical array spacing is half a wavelength, the transmitting carrier frequency is 62 GHz, and the wavelength is 4.8 mm. The echo from the corner reflector received by the array antenna to be calibrated can be considered a plane wave, and the phase difference of the signals received by each antenna is caused by the different path differences between the corner reflector and each antenna.

[0068] Step 2: Obtain radar echo data of each receiving channel of the antenna array to be calibrated at multiple rotation angles, and extract the measured phase value of the corner reflector echo of each receiving channel at each rotation angle based on the radar echo data.

[0069] In this embodiment, the servo turntable can be rotated by computer and rotated within an azimuth angle range of ±10°. At the same time, radar echo data from the corner reflector is collected every 2° interval, for a total of 20 sets of radar echo data from different angles.

[0070] In this embodiment, a 16-bit, 4-channel data acquisition card can be configured to acquire the digital point frequency signal after dechirp (delinear frequency modulation), and the radar echo data of each receiving channel can be sent to a computer for processing via a network port or serial port.

[0071] In this embodiment, the method for extracting the measured phase value includes:

[0072] Step 21: Perform windowed Fourier transform on the radar echo data of each receiving channel at each rotation angle to obtain the spectrum data corresponding to each distance.

[0073] The window function can be the hanning() window, which can reduce spectral leakage and suppress clutter sidelobes.

[0074] Step 22: Determine the range cell number where the corner reflector is located, and extract the spectrum data corresponding to the range cell number. Based on this spectrum data, obtain the measured phase value of the corner reflector echo. The specific formula is as follows:

[0075]

[0076] in, To measure the phase value, arctan is the arctangent function, imag() is the imaginary part of the spectrum data, and real() is the real part of the spectrum data.

[0077] In this embodiment, the range cell number where the corner reflector is located can be calculated by d2 / Δd, where d2 is the preset distance and Δd is the range resolution of the millimeter-wave radar.

[0078] Step 3: For each measured phase value, select the corresponding reference antenna, and perform phase ambiguity removal to obtain the target measured phase value of each receiving channel at each rotation angle. Specifically, this includes:

[0079] Step 31: Determine the horizontal transmission angle of the array antenna to be calibrated at each rotation angle, and perform the following steps for each horizontal transmission angle:

[0080] Step 311: Using the i-th receiving channel as a reference channel, calculate the phase difference between the i-th receiving channel and the (i+1)-th receiving channel;

[0081] Step 312, if θ j <0, and but If θ j >0, and but

[0082] Where, θ j Let j be the j-th horizontal launch angle, where j = 1, 2, 3, ..., m, and m is the number of rotation angles. The measured phase value of the j-th horizontal transmission angle of the i-th receiving channel. The measured phase value of the j-th horizontal transmission angle of the (i+1)-th receiving channel The difference, i.e. i = 1, 2, 3, ..., n, where n is the number of receiving channels;

[0083] Step 313: Calculate the phase difference between each receiving channel and the first receiving channel to obtain the target measurement phase value of each receiving channel, i.e. The target measurement phase value at the j-th horizontal transmission angle of the i-th receiving channel.

[0084] In this embodiment, the millimeter-wave radar includes eight receiving channels. After deambiguation of the phase through the above steps, the target measurement phase values ​​of each receiving channel at different horizontal emission angles are obtained (see [reference needed]). Figure 3 The specific values ​​are shown in the table below:

[0085] Phase value Channel 2 Channel 3 Channel 4 Channel 5 Channel 6 Channel 7 Channel 8 Angle -10° -43 -92 -131 -176 -222 -269 -308 Angle -8° -36 -83 -114 -148 -186 -232 -263 Angle -6° -25 -71 -93 -121 -147 -193 -216 Angle -4° -17 -57 -72 -89 -106 -147 -162 included angle -2° -9 -45 -53 -64 -73 -109 -118 Angle 2° 23 54 56 79 85 112 114 Angle 4° 26 66 74 102 113 148 157 Angle 6° 29 76 89 124 137 180 193 Angle 8° 35 88 107 151 168 219 237 Angle 10° 43 102 126 179 204 260 284

[0086] Step 4: Traverse all target measurement phase values ​​for rotation angles under each receiving channel, and remove the target measurement phase values ​​for rotation angles corresponding to phase value outliers;

[0087] To avoid the influence of clutter-affected phase outliers on the measurement results, in this embodiment, if the target measurement phase value... If the following conditions are met, then Remove:

[0088] and

[0089] in, For the target phase value measured at the j-th horizontal transmission angle of the i-th receiving channel, For the target phase value measured at the (j-1)th horizontal transmission angle of the i-th receiving channel, The target phase value is measured for the (j+1)th horizontal transmission angle of the i-th receiving channel.

[0090] After removing outliers, please refer to the target measurement phase values ​​for each receiving channel. Figure 4 .

[0091] Step 5: Calculate the theoretical phase value of each receiving channel at each rotation angle, and determine the phase correction value of each receiving channel based on the theoretical phase value and the target measured phase value;

[0092] In this embodiment, the formula for calculating the theoretical phase value is as follows:

[0093]

[0094] in, The theoretical phase value of the j-th horizontal transmission angle of the i-th receiving channel, where λ is the wavelength, d is the channel spacing of the uniform linear array antenna, and θ j Let sin(θ) be the horizontal transmission angle of the array antenna to be corrected at each rotation angle. j )≈θ j .

[0095] The method for determining the phase correction value of each receiving channel includes:

[0096] Step 51: Calculate the difference between the measured phase value of the target and the corresponding theoretical phase value to obtain the residual error of each receiving channel at each rotation angle, i.e.:

[0097]

[0098] Among them, e i,j The remaining error for the j-th horizontal transmission angle of the i-th receiving channel;

[0099] It is understandable that the theoretical phase value Phase value with target There is a fixed phase error in the array. And the phase measurement error Δn due to noise i,j Theoretical phase value Phase value with target The relationship between them is:

[0100]

[0101] Subtracting the theoretical phase value from the target measured phase value at all horizontal transmission angles of each receiving channel yields the fixed phase error determined by the array. Phase measurement error Δn due to noise i,j The remaining error e i,j .

[0102] In this embodiment, the theoretical phase values, target measurement phase values, and remaining errors of the eight receiving channels at certain horizontal incident angles are shown in the table below:

[0103]

[0104] Step 52: Normalize the remaining error, that is:

[0105]

[0106] Step 52: For each receiving channel, calculate the average value of the normalized error remaining after all rotation angles and take the conjugate to obtain the phase correction value of the corresponding receiving channel. The calculation formula is as follows:

[0107]

[0108] in,

[0109] The remaining error after processing.

[0110] Step 6: After performing phase correction on the spectrum data of each receiving channel according to the phase correction value, input the data into the beamformer.

[0111] The formula for calculating the phase correction is as follows:

[0112]

[0113] Among them, X i ′ represents the phase-corrected spectral data, X i The spectral data before phase correction. This is the phase correction value for the i-th receiving channel.

[0114] In this embodiment, the beamformer can be a CBF or an MVDR;

[0115] The CBF measures the angle based on the following formula:

[0116]

[0117] The MVDR measures angles based on the following formula:

[0118]

[0119] in, y K For the measurement results, X i ′ represents the phase-corrected spectral data, a i Let i be the array steering vector for the i-th receiving channel. For a i The conjugate of θ K is the Kth scanning azimuth angle within the airspace, and n is the number of receiving channels;

[0120] Take the measurement result y K The angle θ corresponding to the maximum value in K As an angle measurement value θ′:

[0121]

[0122] This embodiment measures the angle using a beamformer (CBF) and MVDR. For measurement accuracy, please refer to [link / reference needed]. Figure 5 It is evident that by performing phase correction on the spectral data of each receiving channel, the accuracy of angle measurement is significantly improved.

[0123] In summary, the array channel calibration method for millimeter-wave radar described in this embodiment, compared with existing millimeter-wave channel calibration methods, can complete the calibration without an anechoic chamber environment, achieves clutter suppression, improves the direction finding accuracy, positioning accuracy and status detection accuracy of millimeter-wave radar, and has lower cost and is easy to implement in large-scale engineering projects.

Claims

1. A method for correcting the array channel of a millimeter-wave radar, characterized in that, Includes the following steps: Step 1: Place the array antenna to be calibrated on a servo turntable at a preset height, and set a corner reflector at a preset distance from the array antenna to be calibrated. The corner reflector is at the same height as the array antenna to be calibrated. Step 2: Obtain radar echo data of each receiving channel of the antenna array to be calibrated at multiple rotation angles, and extract the measured phase value of the corner reflector echo of each receiving channel at each rotation angle based on the radar echo data. Step 3: For each measured phase value, select the corresponding reference antenna, and perform phase ambiguity removal to obtain the target measured phase value of each receiving channel at each rotation angle; Step 3 specifically includes: Step 31: Determine the horizontal transmission angle of the array antenna to be calibrated at each rotation angle, and perform the following steps for each horizontal transmission angle: Step 311, the first Using the receiving channel as a reference channel, calculate the... The receiving channel and the first +1 phase difference value of the receiving channels; Step 312, if <0, and <0.4 Then Updated to ,like >0, and >0.4 Then Updated to ; in, For the first A horizontal launch angle, =1, 2, 3, ... , The number of rotation angles, For the first The receiving channel The measured phase value of each horizontal emission angle With the +1 receiving channel The measured phase value of each horizontal emission angle The difference, i.e. , =1, 2, 3, ... , The number of receive channels; Step 313: Calculate the phase difference between each receiving channel and the first receiving channel to obtain the target measurement phase value of each receiving channel, i.e. , For the first The receiving channel Target phase value at a horizontal launch angle; Step 4: Traverse all target measurement phase values ​​for rotation angles under each receiving channel, and remove the target measurement phase values ​​for rotation angles corresponding to phase value outliers; Step 5: Calculate the theoretical phase value of each receiving channel at each rotation angle, and determine the phase correction value of each receiving channel based on the theoretical phase value and the target measured phase value; The method for determining the phase correction value of each receiving channel includes: Step 51: Calculate the difference between the measured phase value of the target and the corresponding theoretical phase value to obtain the residual error of each receiving channel at each rotation angle, i.e.: ； in, For the first The receiving channel The remaining error of the horizontal launch angle, For the first The receiving channel The theoretical phase value of a horizontal emission angle; Step 52: Normalize the remaining error, that is: ； Step 52: For each receiving channel, calculate the average value of the normalized error remaining after all rotation angles and take the conjugate to obtain the phase correction value of the corresponding receiving channel. The calculation formula is as follows: ； in, For the first Phase correction value for each receiving channel, For the first The receiving channel The remaining error after normalizing the horizontal emission angle; Step 6: After performing phase correction on the spectral data of each receiving channel according to the phase correction value, input the data into the beamformer. The formula for calculating the phase correction is as follows: ； in, This is the phase-corrected spectral data. The spectral data before phase correction. For the first Phase correction value for each receiving channel.

2. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, The radar echo data is a digital point-frequency signal after delinear frequency modulation.

3. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, The preset height is greater than the preset distance, the preset distance is greater than the far-field test distance, and the size of the corner reflector is smaller than the range resolution of the millimeter-wave radar.

4. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, In step 2, the method for extracting the measured phase value includes: Step 21: Perform windowed Fourier transform on the radar echo data of each receiving channel at each rotation angle to obtain the spectrum data corresponding to each distance. Step 22: Determine the range cell number where the corner reflector is located, and extract the spectrum data corresponding to the range cell number. Based on this spectrum data, obtain the measured phase value of the corner reflector echo. The specific formula is as follows: ； in, To measure the phase value, It is the arctangent function. This is the imaginary part of the spectrum data. This represents the real part of the spectrum data.

5. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, Step 4 specifically includes: If the target measurement phase value If the following conditions are met, then Remove: ,and ; in, For the first The receiving channel Target phase value at a horizontal launch angle For the first The receiving channel -1 horizontal launch angle target measurement phase value, For the first The receiving channel +1 horizontal launch angle target measurement phase value.

6. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, In step 5, the formula for calculating the theoretical phase value is as follows: ； in, For the first The receiving channel The theoretical phase value of a horizontal emission angle, For wavelength, For uniform linear array antenna channel spacing, The horizontal transmission angle of the array antenna to be corrected at each rotation angle. .

7. The array channel correction method for millimeter-wave radar as described in claim 1, characterized in that, In step 6, the beamformer is a CBF or MVDR; The CBF measures the angle based on the following formula: ； The MVDR measures angles based on the following formula: ； in, , For the measurement results, This is the phase-corrected spectral data. For the first Array steering vectors for each receiving channel, for conjugate, For the first in the airspace One scanning azimuth angle The number of receive channels; Take measurement results The angle corresponding to the maximum value in As an angle measurement value : 。

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