Method, device, equipment and medium for improving angle measurement accuracy of millimeter wave radar

Abstract

The invention provides a method, a device, equipment and a medium for improving the angle measurement accuracy of a millimeter-wave radar, and the method comprises the steps: driving the millimeter-wave radar to rotate at a constant speed through a control rotary table, and enabling a to-be-detected target to be located at different detection angles of the millimeter-wave radar. And controlling the millimeter-wave radar to perform detection every preset time period, and obtaining multiple echo data during multiple times of detection. And processing each piece of echo data to obtain a plurality of pieces of phase information. And performing fitting based on the multiple pieces of phase information and the turntable angle corresponding to each piece of phase information, and determining an antenna phase center distance and an initial phase difference. And determining a steering vector based on the antenna phase center distance, the initial phase difference and the plurality of preset detection angles. And determining a target detection angle of the to-be-detected target based on the steering vector and the phase information. And based on the target detection angle and the turntable angle corresponding to the target detection angle, determining a detection angle error so as to compensate the angle of the millimeter wave radar detection target based on the detection angle error.

Description

Technical Field

[0001] This application relates to the field of radar technology, specifically to a method, apparatus, device, and medium for improving the angle measurement accuracy of millimeter-wave radar. Background Technology

[0002] With the development of automotive intelligence, the requirements for Advanced Driver Assistance Systems (ADAS) are becoming increasingly stringent. Millimeter-wave radar plays a crucial role in ADAS systems, providing essential detection capabilities to ensure the safety of autonomous driving. For example, millimeter-wave radar can detect targets in front of the vehicle, providing information such as the target's distance, angle, and speed, assisting the ADAS system in controlling the vehicle to avoid these targets. To ensure the safety of autonomous driving, strict performance requirements are placed on millimeter-wave radar, especially the accuracy of target angle measurement.

[0003] In practice, the target detection angle is typically determined based on the spacing between millimeter-wave radar antennas and the phase difference between them. However, due to manufacturing variations in millimeter-wave radar production processes, errors may occur in the antenna spacing and initial phase, leading to significant errors in the target detection angle and impacting the vehicle's intelligent driving capabilities.

[0004] Current calibration methods involve acquiring phase values ​​at different angles when the millimeter-wave radar detects a target, fitting a curve showing the relationship between the antenna's phase difference and angle change. The intercept of this curve represents the phase error that needs to be compensated, and the antenna phase center spacing of the receiving antenna is determined based on the slope of the curve. A drawback of this method is that if the error during the fitting process is large, the fitting result cannot accurately represent the relationship between phase difference and angle within the millimeter-wave radar's angular measurement range. At certain angles (especially large angles), the angular measurement accuracy may still be low. Summary of the Invention

[0005] In view of this, this application aims to provide a method, apparatus, device, and medium for improving the accuracy of angle measurement by millimeter-wave radar, so as to improve the accuracy of millimeter-wave radar in detecting target angles.

[0006] In a first aspect, this application provides a method for improving the angle measurement accuracy of millimeter-wave radar, the method comprising:

[0007] In response to the turntable driving the millimeter-wave radar to rotate at a constant speed, the millimeter-wave radar is controlled to detect the target to be detected at preset time intervals, and multiple echo data of the millimeter-wave radar are acquired. The target to be detected is simulated using an echo simulator, and the rotation range is the angle measurement range of the millimeter-wave radar.

[0008] The echo data is processed to obtain the phase information of the millimeter-wave radar;

[0009] The antenna phase center spacing and initial phase difference are determined by fitting multiple phase information and the turntable angle corresponding to the phase information;

[0010] The guiding vector is determined based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles.

[0011] Based on the guide vector and the phase information, the target detection angle of the target to be detected is determined from a plurality of preset detection angles;

[0012] Based on the target detection angle and the turntable angle corresponding to the target detection angle, a detection angle error is determined so as to compensate for the angle of other targets detected by the millimeter-wave radar.

[0013] In one possible implementation, the method further includes:

[0014] The millimeter-wave radar acquires multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to multiple different times, wherein the multiple times are within the total time during which the turntable rotates within the angle measurement range;

[0015] In response to the millimeter-wave radar detecting other targets at the initial target detection angle, the target detection angle range in which the initial target detection angle is located is determined based on multiple target detection angle reference values.

[0016] Determine the detection angle error range corresponding to the target detection angle range;

[0017] Linear interpolation is performed based on the initial target detection angle, the target detection angle range, and the detection angle error range to determine the target detection angle error corresponding to the initial target detection angle.

[0018] Based on the initial target detection angle and the target detection angle error, the true value of the target detection angle of the other targets is determined.

[0019] In one possible implementation, the multiple phase information values ​​respectively correspond to multiple target detection angles, and the step of obtaining multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to the millimeter-wave radar at multiple different times includes:

[0020] Obtain the total time required for the turntable to rotate through the entire angular measurement range;

[0021] For a first time among the plurality of times, a first ratio of the first time to the total time is calculated, and the first product of the first ratio and the total number of detections by the millimeter-wave radar is calculated, wherein the first time represents any time among the plurality of times;

[0022] Based on the first product, a target detection angle reference value corresponding to the first time is determined among the multiple target detection angles;

[0023] Based on the first time and the angular velocity of the turntable, determine the turntable angle corresponding to the first time;

[0024] Based on the target detection angle reference value corresponding to the first time and the turntable angle corresponding to the first time, the detection angle error reference value corresponding to the first time is determined.

[0025] In one possible implementation, the step of determining the target detection angle error corresponding to the initial target detection angle by performing linear interpolation calculation based on the initial target detection angle, the target detection angle interval, and the detection angle error interval includes:

[0026] Calculate the first difference between the initial detection angle and the first target detection angle reference value, where the first target detection angle reference value represents the left endpoint of the target detection angle interval and the second target detection angle reference value represents the right endpoint of the target detection angle interval;

[0027] Calculate the second difference between the second target detection angle reference value and the first target detection angle reference value;

[0028] Calculate the second ratio of the first difference to the second difference;

[0029] Calculate the third difference between the second detection angle error reference value and the first detection angle error reference value, where the first detection angle error reference value represents the left endpoint of the detection angle error interval and the second detection angle error reference value represents the right endpoint of the detection angle error interval.

[0030] Calculate the second product of the second ratio and the third difference;

[0031] The sum of the second product and the first detection angle error reference value is calculated to determine the target detection angle error.

[0032] In one possible implementation, N preset detection angles are determined based on the angle measurement range, and the millimeter-wave radar includes M channels, each channel corresponding to an antenna phase center spacing and an initial phase difference;

[0033] The step of determining the steering vector based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles includes:

[0034] For the i-th preset detection angle and the m-th channel, based on the antenna phase center spacing and initial phase difference corresponding to the m-th channel, and the i-th preset detection angle, determine the element in the i-th row and m-th column of the guide vector.

[0035] In one possible implementation, determining the target detection angle of the target to be detected among a plurality of preset detection angles based on the guide vector and the phase information includes:

[0036] The product matrix is ​​obtained by multiplying the steering vector and the phase information;

[0037] Determine the integers in the product matrix;

[0038] The preset detection angle corresponding to the integer in the guide vector is determined as the target detection angle.

[0039] In one possible implementation, the millimeter-wave radar includes multiple channels, each corresponding to a phase information.

[0040] The step of fitting based on multiple phase information and the turntable angle corresponding to the phase information to determine the antenna phase center spacing and initial phase difference includes:

[0041] A reference channel and a target channel are determined, and the phase difference is determined based on the phase information of the reference channel and the phase information of the target channel;

[0042] A linear function relationship is determined by fitting the results of multiple phase differences and the sine value of the turntable angle corresponding to each phase difference.

[0043] The intercept of the linear function relationship is determined as the initial phase difference of the target channel;

[0044] Calculate the third product between the slope of the linear function and the wavelength of the millimeter-wave radar, and calculate the ratio of the third product to 2π to obtain the antenna phase center spacing.

[0045] Secondly, this application provides an apparatus for improving the angle measurement accuracy of millimeter-wave radar, the apparatus comprising:

[0046] The detection unit is used to respond to the turntable driving the millimeter-wave radar to rotate at a constant speed, control the millimeter-wave radar to detect the target to be detected at preset time intervals, and acquire multiple echo data of the millimeter-wave radar. The target to be detected is simulated using an echo simulator, and the rotation range is the angle measurement range of the millimeter-wave radar.

[0047] The processing unit is used to process the echo data to obtain the phase information of the millimeter-wave radar;

[0048] A fitting unit is used to perform fitting based on multiple phase information and the turntable angle corresponding to the phase information to determine the antenna phase center spacing and the initial phase difference;

[0049] The first determining unit is used to determine the guiding vector based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles;

[0050] The second determining unit is used to determine the target detection angle of the target to be detected from multiple preset detection angles based on the guiding vector and the phase information.

[0051] The third determining unit is used to determine the detection angle error based on the target detection angle and the turntable angle corresponding to the target detection angle, so as to compensate for the angle of other targets detected by the millimeter-wave radar based on the detection angle error.

[0052] Thirdly, this application provides an electronic device, the device comprising: a memory and a processor;

[0053] The memory is used to store the relevant program code;

[0054] The processor is used to call the program code to execute the method for improving the angle measurement accuracy of millimeter-wave radar as described in any of the implementations of the first aspect above.

[0055] Fourthly, this application provides a computer-readable storage medium for storing a computer program for executing the method for improving the angle measurement accuracy of millimeter-wave radar as described in any implementation of the first aspect above.

[0056] Fifthly, this application provides a computer program product, which includes a computer program / instruction, and when the computer program / instruction is executed by a processor, it implements the method for improving the angle measurement accuracy of millimeter-wave radar as described in any of the implementations of the first aspect.

[0057] In the above implementation of this application, the millimeter-wave radar can be operated in a microwave anechoic chamber. The millimeter-wave radar is placed on a turntable, and the turntable is controlled to rotate the millimeter-wave radar at a uniform speed, thus positioning the target to be detected at different detection angles of the millimeter-wave radar. The rotation range of the turntable is the angular measurement range of the millimeter-wave radar, and the target to be detected is simulated using an echo simulator. After receiving the electromagnetic waves emitted by the millimeter-wave radar, the echo simulator can transmit information carrying the target to be detected in the form of electromagnetic waves back to the millimeter-wave radar as an echo. The millimeter-wave radar is controlled to perform detection at preset time intervals, thereby acquiring multiple echo data from multiple detections. Each echo data is processed to obtain multiple phase information of the millimeter-wave radar. Based on the multiple phase information and the corresponding turntable angle, a fitting process is performed to determine the antenna phase center distance and the initial phase difference. Based on the antenna phase center distance, the initial phase difference, and the multiple preset detection angles of the millimeter-wave radar, the steering vector is determined. In other words, multiple preset detection angles can be predetermined within the angular measurement range of the millimeter-wave radar to determine the target detection angle of the target to be detected. Based on the steering vector and phase information, the target detection angle of the target to be detected is determined from multiple preset detection angles. Based on the target detection angle and the corresponding turntable angle, the detection angle error is determined so as to compensate for the angle of the target detected by the millimeter-wave radar. The method provided in this application can more accurately determine the initial phase difference and the antenna phase center distance of the millimeter-wave radar antenna. Furthermore, it can determine the detection angle error between the turntable angle and the target detection angle of the millimeter-wave radar during turntable rotation. Subsequently, when the millimeter-wave radar detects other targets, the corresponding detection angle error is used to compensate for the detected angle, thereby improving the accuracy of the millimeter-wave radar in detecting target angles. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments provided in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0059] Figure 1 A flowchart illustrating a method for improving the angle measurement accuracy of millimeter-wave radar, provided as an embodiment of this application.

[0060] Figure 2 This is a schematic diagram of a device for improving the angle measurement accuracy of millimeter-wave radar, provided as an embodiment of this application.

[0061] Figure 3 This is a schematic diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0062] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are merely exemplary implementations of this application and not all implementation methods. Those skilled in the art can obtain other embodiments in conjunction with the embodiments of this application without creative effort, and these embodiments are also within the protection scope of this application.

[0063] When using millimeter-wave radar to detect targets, the detection angle is typically determined based on the spacing between the radar antennas and the phase difference between them. However, due to manufacturing variations or differences in the installation process, errors can occur in the antenna spacing and initial phase, leading to significant errors in the target detection angle and impacting the vehicle's intelligent driving capabilities.

[0064] Currently, the calibration method for millimeter-wave radar involves acquiring phase values ​​at different angles when the millimeter-wave radar detects a target, fitting a curve showing the relationship between the antenna's phase difference and the angle change. The intercept of this curve represents the phase error that needs to be compensated, and the antenna phase center spacing of the receiving antenna is determined based on the slope of the curve. The drawback of this method is that if the error in the fitting process is large, the fitting result cannot accurately represent the relationship between the phase difference and the angle within the angular measurement range of the millimeter-wave radar, and accuracy may still be low at certain angles (especially large angles).

[0065] Based on this, this application provides a method to improve the angle measurement accuracy of millimeter-wave radar, thereby enhancing the accuracy of target angle detection by the millimeter-wave radar. Specifically, the millimeter-wave radar is placed on a turntable, and the turntable is controlled to rotate the millimeter-wave radar at a constant speed, thus positioning the target to be detected at different detection angles of the millimeter-wave radar. The rotation range of the turntable is the angle measurement range of the millimeter-wave radar, and the target to be detected is simulated using an echo simulator. The echo simulator, after receiving the electromagnetic waves emitted by the millimeter-wave radar, transmits information carrying the target to be detected as electromagnetic waves back to the millimeter-wave radar as an echo. The millimeter-wave radar is controlled to perform detection at preset time intervals, thereby acquiring multiple echo data from multiple detections. Each echo data is processed to obtain multiple phase information of the millimeter-wave radar. Based on the multiple phase information and the corresponding turntable angle, a fitting method is used to determine the antenna phase center spacing and the initial phase difference. Based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles, a steering vector is determined. In other words, multiple preset detection angles can be pre-determined within the angular measurement range of the millimeter-wave radar to determine the target detection angle of the target to be detected among these preset angles. Based on the steering vector and phase information, the target detection angle of the target to be detected is determined from among the multiple preset detection angles. Based on the target detection angle and the corresponding turntable angle, the detection angle error is determined so as to compensate for the angle of other targets detected by the millimeter-wave radar. Through the method provided in this application embodiment, the initial phase difference and antenna phase center spacing of the millimeter-wave radar antenna can be determined more accurately. Furthermore, during the turntable rotation process, the detection angle error between the turntable angle and the target detection angle of the millimeter-wave radar can be determined. Subsequently, when the millimeter-wave radar detects other targets, the corresponding detection angle error is used to compensate for the detected angle, thereby improving the accuracy of the millimeter-wave radar in detecting target angles.

[0066] To facilitate understanding of the technical solutions provided in the embodiments of this application, a detailed description will be given below in conjunction with the accompanying drawings.

[0067] See Figure 1 The diagram shown is a flowchart of a method for improving the angle measurement accuracy of millimeter-wave radar according to an embodiment of this application.

[0068] This method can be executed by the radar's host computer. The method may include the following steps:

[0069] S101: In response to the turntable driving the millimeter-wave radar to rotate at a constant speed, the millimeter-wave radar is controlled to detect the target to be detected at preset time intervals, and multiple echo data of the millimeter-wave radar are acquired.

[0070] It can be used to operate millimeter-wave radar in a microwave anechoic chamber. The microwave anechoic chamber is lined with microwave absorbing materials to absorb electromagnetic waves, reduce the reflection or escape of electromagnetic waves, and ensure the accuracy of measurement results.

[0071] A turntable is placed in a microwave anechoic chamber, and a millimeter-wave radar is placed on the turntable. By controlling the turntable to rotate at a constant speed, the millimeter-wave radar is also rotated at a constant speed, so that the target to be detected is located at different detection angles of the millimeter-wave radar. The rotation range of the turntable corresponds to the angular measurement range of the millimeter-wave radar. For example, if the angular measurement range of the millimeter-wave radar is [-60°, 60°], the turntable can be controlled to start rotating from the maximum negative angle of the millimeter-wave radar at -60° and stop when it reaches the maximum positive angle of 60°. During the constant rotation of the turntable, the millimeter-wave radar is controlled to detect the target at preset time intervals, that is, the millimeter-wave radar is controlled to emit electromagnetic waves to detect the target.

[0072] Optionally, the radar can be controlled to start working and detect the target at the same time the turntable starts rotating, and then the target can be detected again at preset time intervals. For example, the millimeter-wave radar can be controlled to detect the target once every 25ms.

[0073] The turntable can be controlled by a turntable control device to rotate at a constant speed, with the angular velocity of the turntable expressed as α rad / s. During the rotation of the turntable, the radar can transmit beams and receive echoes at fixed intervals (preset time intervals) to detect the target.

[0074] The target to be detected can be simulated using an echo simulator. The echo simulator can simulate the target based on a preset distance, preset velocity, and radar cross-section. After receiving electromagnetic waves emitted by the millimeter-wave radar, the echo simulator can transmit electromagnetic waves carrying information about the target to the millimeter-wave radar as its echo. In this embodiment, the preset velocity of the target can be set to 0, meaning the target remains stationary.

[0075] Millimeter-wave radar detects the target at preset time intervals, thus acquiring a corresponding echo data point. This allows for multiple echo data points corresponding to multiple detections. The detection angle of the millimeter-wave radar for detecting the target also varies as it rotates.

[0076] S102: Process the echo data to obtain the phase information of the millimeter-wave radar.

[0077] After acquiring multiple echo data from the millimeter-wave radar, each echo data is processed to obtain the phase information corresponding to each echo data.

[0078] Specifically, a two-dimensional fast Fourier transform (2D-FFT) can be performed on the echo data to obtain the range-Doppler spectrum matrix. Each data point in the range-Doppler spectrum matrix is ​​a complex number, composed of amplitude and phase. Based on the preset distance and velocity corresponding to the target, the position of the target in the range-Doppler spectrum matrix is ​​determined, and the corresponding phase information at that position is obtained.

[0079] S103: Based on multiple phase information and the turntable angle corresponding to each phase information, the antenna phase center spacing and initial phase difference are determined by fitting.

[0080] After processing multiple echo data from the millimeter-wave radar, multiple phase information can be obtained. Each phase information is obtained by detecting the target during the rotation of the millimeter-wave radar, and the time of receiving the echo corresponding to each phase information can be determined. Since the turntable rotates at a constant speed, the product of the time of receiving the echo corresponding to each phase information and the angular velocity of the turntable's uniform rotation can be calculated to obtain the turntable angle corresponding to each phase information. Then, based on multiple phase information and the turntable angle corresponding to each phase information, a fitting process is performed to determine the antenna phase center spacing and the initial phase difference.

[0081] In practical applications, millimeter-wave radar comprises multiple channels. After each beam transmission, each channel receives an echo data point, corresponding to a phase information point. In one possible implementation, a reference channel and a target channel can be identified among the multiple channels. For example, the reference channel could be the leftmost or rightmost channel, or any other channel. The target channel is any channel other than the reference channel; that is, there can be multiple target channels. During the same detection process, a phase difference is determined based on the phase information of the reference channel and the target channel, thus allowing for the determination of multiple phase differences between the reference channel and the target channel during multiple detections.

[0082] A linear function relationship for the target channel is determined by fitting multiple phase differences and the sine value of the turntable angle corresponding to each phase difference. For example, the linear function relationship can be expressed as y = ksinβ + b, where y represents the phase difference and β represents the turntable angle. The intercept of the linear function relationship is determined as the initial phase difference of the target channel, i.e., b, representing the inherent phase error of the target channel. The product of the slope of the linear function relationship and the wavelength of the millimeter-wave radar is calculated, and the ratio of the product to 2π is calculated to obtain the antenna phase center spacing. That is, the product of the slope k and the wavelength is calculated and then divided by 2π to obtain the antenna phase center spacing, i.e., the calibrated antenna spacing. In other words, each channel has its own antenna phase center spacing and initial phase difference.

[0083] S104: Determine the steering vector based on the antenna phase center spacing, initial phase difference, and multiple preset detection angles.

[0084] The multiple preset detection angles can be determined by the angle measurement range of the millimeter-wave radar. For example, within the angle measurement range, a preset detection angle is determined at fixed angle intervals, thus allowing for the determination of multiple preset detection angles. For instance, when the angle measurement range is [-60°, 60°], a preset detection angle can be taken at 1° intervals, resulting in 121 preset detection angles.

[0085] In one possible implementation, the steering vector can be determined as follows: N preset detection angles can be determined based on the angular measurement range. The millimeter-wave radar includes M channels, each corresponding to an antenna phase center spacing and an initial phase difference. Specifically, for the i-th preset detection angle and the m-th channel, based on the antenna phase center spacing and initial phase difference corresponding to the m-th channel, and the i-th preset detection angle, the element in the i-th row and m-th column of the steering vector is determined. That is, each row of the steering vector corresponds to a preset detection angle, and each column corresponds to a channel, so the steering vector can be represented as an N×M matrix. Optionally, the row vector of the steering vector can be represented as:

[0086] In this formula, j represents the complex part, θ represents the preset detection angle corresponding to each row, λ represents the wavelength, and d(M) represents the antenna phase center spacing corresponding to the Mth channel. This represents the initial phase difference corresponding to the Mth channel.

[0087] S105: Determine the target detection angle of the target to be detected based on the guide vector and phase information.

[0088] The elements of the range-Doppler spectrum matrix can typically be represented as: A represents the amplitude. This represents the phase. Each channel corresponds to a phase information, therefore the phase information acquired during each detection can be represented as... That is, the phase information is a column vector. This represents the phase information corresponding to the Mth channel.

[0089] When a target to be detected exists at the preset detection angle θ, the guide vector... and They are equal, at this point... and complex power of e Multiplying them cancels out the complex parts, resulting in an integer, thus determining θ as the target detection angle. In other words,

[0090] Specifically, the guide vector and the vector corresponding to the complex power of e of the phase information can be multiplied to obtain a product matrix. When there is an integer in the product matrix, the preset detection angle corresponding to that integer in the guide vector is determined as the target detection angle. That is, the row number corresponding to that integer in the product matrix is ​​determined, and then the preset detection angle corresponding to that row number in the guide vector is determined as the target detection angle.

[0091] S106: Based on the target detection angle and the turntable angle corresponding to the target detection angle, determine the detection angle error so as to compensate for the angle of the target detected by the millimeter-wave radar based on the detection angle error.

[0092] During each detection, the corresponding detection time can be determined, thus defining the detection time for each target detection angle. Since the turntable rotates at a constant speed, the product of the detection time corresponding to the target detection angle and the angular velocity of the turntable's constant rotation can be calculated to obtain the turntable angle corresponding to the target detection angle. Because the millimeter-wave radar performs multiple detections of the target during the turntable's rotation, multiple target detection angles corresponding to these multiple detections can be determined.

[0093] For each target detection angle and the corresponding turntable angle, the detection angle error is determined. In other words, there is an error between the turntable angle and the target detection angle detected by the millimeter-wave radar. When using the millimeter-wave radar to detect other targets, this detection angle error can be used to compensate for the angles at which the millimeter-wave radar detects other targets, thereby improving the accuracy of target angle detection by the millimeter-wave radar.

[0094] The method provided in the above embodiments can more accurately determine the initial phase difference and the antenna phase center spacing of the millimeter-wave radar antenna. Furthermore, during the rotation of the turntable, the detection angle error between the turntable angle and the target detection angle of the millimeter-wave radar can be determined. Subsequently, when the millimeter-wave radar detects other targets, the corresponding detection angle error can be used to compensate for the detection angle, thereby improving the accuracy of the millimeter-wave radar in detecting target angles.

[0095] As can be seen from the above embodiments, since the millimeter-wave radar detects the target at preset time intervals, the target detection angle and detection angle error corresponding to multiple detections by the millimeter-wave radar can be determined respectively. In order to more accurately compensate for the angle measurement of the millimeter-wave radar, more fine-grained detection angle errors can be determined based on the target detection angle and detection angle error corresponding to the multiple detections, so as to compensate for the angle of the target detected by the millimeter-wave radar.

[0096] In one possible implementation, the process may include the following steps A1-A5:

[0097] A1: Obtain multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to millimeter-wave radar at multiple different times.

[0098] Among these, the aforementioned multiple times fall within the total time of the turntable's rotation within the angular measurement range. In other words, more times can be determined within the total time, allowing for the estimation of the target detection angle reference value and the detection angle error reference value at each time point when detecting the target.

[0099] In specific implementation, the total time required for the turntable to complete the angular measurement range is obtained. For a first time among multiple times, a first ratio of the first time to the total time is calculated, and a first product of the first ratio and the total number of detections by the millimeter-wave radar is calculated, where the first time represents any time among multiple times. Based on the first product, a target detection angle reference value corresponding to the first time is determined among multiple target detection angles. Based on the method of the above embodiment, the target detection angle determined each time the millimeter-wave radar detects the target can be determined. Within the total time T, there is a corresponding total number of millimeter-wave radar detections C. Therefore, the number of millimeter-wave radar detections corresponding to the first time t can be determined, i.e., the first product is expressed as t / T*C. The first product is rounded up to obtain the number of millimeter-wave radar detections corresponding to the first time t. Thus, the target detection angle corresponding to this number of detections can be determined as the target detection angle reference value corresponding to the first time.

[0100] Since the turntable rotates at a constant speed, the turntable angle corresponding to the first time point can be determined based on the turntable's angular velocity. Based on the target detection angle reference value and the turntable angle corresponding to the first time point, the detection angle error reference value corresponding to the first time point can be determined. By performing the above steps for each time point, multiple target detection angle reference values ​​and multiple detection angle error reference values ​​can be determined for multiple time points.

[0101] A2: The initial target detection angle is determined based on the angle at which the millimeter-wave radar detects other targets. The target detection angle range in which the initial target detection angle is located is determined based on multiple target detection angle reference values.

[0102] When the millimeter-wave radar detects a target, the detected angle is the initial target detection angle. It can be determined which interval of multiple target detection angle reference values ​​this initial target detection angle falls within, thus defining the target detection angle interval in which the initial target detection angle lies. Optionally, this target detection angle interval can be the smallest interval among the multiple target detection angle reference values ​​to minimize errors. For example, when the multiple target detection angle reference values ​​include 0°, 3°, 5°, and 10°, and the initial target detection angle is 4°, then the target detection angle interval in which the initial target detection angle lies is [3°, 5°].

[0103] A3: Determine the detection angle error range corresponding to the target detection angle range.

[0104] Since the target detection angle reference value and the detection angle error reference value are in one-to-one correspondence, after determining the target detection angle range, the detection angle error range corresponding to the target detection angle range can be determined from multiple detection angle error reference values.

[0105] A4: Based on the initial target detection angle, the target detection angle range, and the detection angle error range, linear interpolation calculation is performed to determine the target detection angle error corresponding to the initial target detection angle.

[0106] In specific implementation, a first target detection angle reference value represents the left endpoint of the target detection angle interval, and a second target detection angle reference value represents the right endpoint of the target detection angle interval. Then, the first difference between the initial target detection angle and the first target detection angle reference value is calculated. Next, the second difference between the second target detection angle reference value and the first target detection angle reference value is calculated, which represents the length of the target detection angle interval. Finally, the second ratio between the first difference and the second difference is calculated.

[0107] The first detection angle error reference value represents the left endpoint of the detection angle error interval, and the second detection angle error reference value represents the right endpoint of the detection angle error interval. The third difference between the second detection angle error reference value and the first detection angle error reference value is calculated, which is the length of the detection angle error interval.

[0108] Calculate the second product of the second ratio and the third difference, and then calculate the sum of the second product and the first detection angle error reference value to determine the target detection angle error.

[0109] In one possible implementation, when determining the first difference, the difference between the second target detection angle reference value and the initial target detection angle can also be calculated as the first difference. The second product is calculated in the same way. Then, the difference between the second detection angle error reference value and the second product is calculated as the target detection angle error.

[0110] A5: Determine the true value of the target detection angle based on the initial target detection angle and the target detection angle error.

[0111] By determining multiple reference values ​​for the detection angle error between the turntable angle and the target detection angle reference value at multiple different times, multiple detection angle errors can be determined more precisely. Subsequently, when compensating for the initial target detection angle of the millimeter-wave radar, the target detection angle error corresponding to the initial target detection angle can be determined more accurately, thereby improving the accuracy of the millimeter-wave radar in detecting target angles.

[0112] Based on the above method embodiments, this application also provides an apparatus for improving the angle measurement accuracy of millimeter-wave radar. See also Figure 2 The diagram shown is a schematic of a device for improving the angle measurement accuracy of millimeter-wave radar according to an embodiment of this application.

[0113] The device 200 includes:

[0114] The detection unit 201 is used to respond to the turntable driving the millimeter-wave radar to rotate at a constant speed, control the millimeter-wave radar to detect the target to be detected at preset time intervals, and acquire multiple echo data of the millimeter-wave radar. The target to be detected is simulated using an echo simulator, and the rotation range is the angle measurement range of the millimeter-wave radar.

[0115] The processing unit 202 is used to process the echo data to obtain the phase information of the millimeter-wave radar;

[0116] The fitting unit 203 is used to perform fitting based on multiple phase information and the turntable angle corresponding to the phase information to determine the antenna phase center spacing and the initial phase difference;

[0117] The first determining unit 204 is used to determine the guiding vector based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles;

[0118] The second determining unit 205 is used to determine the target detection angle of the target to be detected from a plurality of preset detection angles based on the guiding vector and the phase information.

[0119] The third determining unit 206 is used to determine the detection angle error based on the target detection angle and the turntable angle corresponding to the target detection angle, so as to compensate for the angle of other targets detected by the millimeter-wave radar based on the detection angle error.

[0120] In one possible implementation, the device further includes: an acquisition unit, configured to acquire multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to the millimeter-wave radar at multiple different times, wherein the multiple times are within the total time during which the turntable rotates within the angle measurement range;

[0121] The device further includes: a fourth determining unit, configured to, in response to the millimeter-wave radar detecting other targets at an initial target detection angle, determine a target detection angle interval in which the initial target detection angle is located based on multiple target detection angle reference values; determine a detection angle error interval corresponding to the target detection angle interval; perform linear interpolation calculation based on the initial target detection angle, the target detection angle interval, and the detection angle error interval to determine the target detection angle error corresponding to the initial target detection angle; and determine the true value of the target detection angle of the other targets based on the initial target detection angle and the target detection angle error.

[0122] In one possible implementation, the multiple phase information values ​​correspond to multiple target detection angles. The acquisition unit is specifically used to acquire the total time required for the turntable to complete the angle measurement range; for a first time among the multiple times, calculate a first ratio of the first time to the total time, and a first product of the first ratio and the total number of detections performed by the millimeter-wave radar, where the first time represents any time among the multiple times; based on the first product, determine a target detection angle reference value corresponding to the first time among the multiple target detection angles; based on the first time and the angular velocity of the turntable, determine the turntable angle corresponding to the first time; based on the target detection angle reference value corresponding to the first time and the turntable angle corresponding to the first time, determine a detection angle error reference value corresponding to the first time.

[0123] In one possible implementation, the fourth determining unit is specifically used to calculate a first difference between the initial detection angle and a first target detection angle reference value, where the first target detection angle reference value represents the left endpoint of the target detection angle interval and the second target detection angle reference value represents the right endpoint of the target detection angle interval; calculate a second difference between the second target detection angle reference value and the first target detection angle reference value; calculate a second ratio between the first difference and the second difference; calculate a third difference between a second detection angle error reference value and the first detection angle error reference value, where the first detection angle error reference value represents the left endpoint of the detection angle error interval and the second detection angle error reference value represents the right endpoint of the detection angle error interval; calculate a second product of the second ratio and the third difference; and calculate the sum of the second product and the first detection angle error reference value to determine the target detection angle error.

[0124] In one possible implementation, N preset detection angles are determined based on the angle measurement range, and the millimeter-wave radar includes M channels, each channel corresponding to an antenna phase center spacing and an initial phase difference;

[0125] The first determining unit 204 is specifically used to determine the element in the i-th row and m-th column of the guiding vector based on the antenna phase center spacing and initial phase difference corresponding to the m-th channel and the i-th preset detection angle.

[0126] In one possible implementation, the second determining unit 205 is specifically used to multiply the guide vector and the phase information to obtain a product matrix; determine the integer in the product matrix; and determine the preset detection angle corresponding to the integer in the guide vector as the target detection angle.

[0127] In one possible implementation, the millimeter-wave radar includes multiple channels, each corresponding to a phase information.

[0128] The fitting unit 203 is specifically used to determine a reference channel and a target channel, and to determine a phase difference based on the phase information of the reference channel and the phase information of the target channel; to perform fitting based on multiple phase differences and the sine value of the turntable angle corresponding to each phase difference to determine a linear function relationship; to determine the intercept of the linear function relationship as the initial phase difference of the target channel; to calculate the third product between the slope of the linear function relationship and the wavelength of the millimeter-wave radar, and to calculate the ratio of the third product to 2π to obtain the antenna phase center spacing.

[0129] Based on the above method and device embodiments, this application also provides an electronic device. The following description will be provided in conjunction with the accompanying drawings.

[0130] See Figure 3 , Figure 3 This is a schematic diagram of an electronic device provided in an embodiment of this application.

[0131] The device 300 includes: a memory 301 and a processor 302;

[0132] The memory 301 is used to store relevant program code;

[0133] The processor 302 is used to call the program code and execute the method for improving the angle measurement accuracy of millimeter-wave radar as described in the above method embodiments.

[0134] Furthermore, embodiments of this application also provide a computer-readable storage medium for storing a computer program for executing the method for improving the angle measurement accuracy of millimeter-wave radar as described in the above-described method embodiments.

[0135] This application also provides a computer program product, which includes a computer program / instruction. When the computer program / instruction is executed by a processor, it implements the method for improving the angle measurement accuracy of millimeter-wave radar as described in the above method embodiments.

[0136] It should be noted that the computer-readable medium described above in this application may be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium may be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0137] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Mava and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0138] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. In particular, for system or device embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The device embodiments described above are merely illustrative. The units or modules described as separate components may or may not be physically separate. The components shown as units or modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network units. Some or all of the units or 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 creative effort.

[0139] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functions, and operations that may be implemented by methods, apparatuses, and devices 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 the specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated 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 the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0140] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0141] It should also be noted that, in this application, relational terms such as "first" and "second" are used merely 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.

[0142] The steps of the methods or algorithms described in conjunction with the embodiments disclosed in this application can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0143] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving the angle measurement accuracy of millimeter-wave radar, characterized in that, The method includes: In response to the turntable driving the millimeter-wave radar to rotate at a constant speed, the millimeter-wave radar is controlled to detect the target to be detected at preset time intervals, and multiple echo data of the millimeter-wave radar are acquired. The target to be detected is simulated using an echo simulator, and the rotation range is the angle measurement range of the millimeter-wave radar. The echo data is processed to obtain the phase information of the millimeter-wave radar; The antenna phase center spacing and initial phase difference are determined by fitting multiple phase information and the turntable angle corresponding to the phase information; The guiding vector is determined based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles. Based on the guide vector and the phase information, the target detection angle of the target to be detected is determined from a plurality of preset detection angles; Based on the target detection angle and the turntable angle corresponding to the target detection angle, a detection angle error is determined so as to compensate for the angle of other targets detected by the millimeter-wave radar.

2. The method according to claim 1, characterized in that, The method further includes: The millimeter-wave radar acquires multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to multiple different times, wherein the multiple times are within the total time during which the turntable rotates within the angle measurement range; In response to the millimeter-wave radar detecting other targets at the initial target detection angle, the target detection angle range in which the initial target detection angle is located is determined based on multiple target detection angle reference values. Determine the detection angle error range corresponding to the target detection angle range; Linear interpolation is performed based on the initial target detection angle, the target detection angle range, and the detection angle error range to determine the target detection angle error corresponding to the initial target detection angle. Based on the initial target detection angle and the target detection angle error, the true value of the target detection angle of the other targets is determined.

3. The method according to claim 2, characterized in that, The multiple phase information values ​​correspond to multiple target detection angles, and the step of obtaining multiple detection angle error reference values ​​and multiple target detection angle reference values ​​corresponding to the millimeter-wave radar at multiple different times includes: Obtain the total time required for the turntable to rotate through the entire angular measurement range; For a first time among the plurality of times, a first ratio of the first time to the total time is calculated, and the first product of the first ratio and the total number of detections by the millimeter-wave radar is calculated, wherein the first time represents any time among the plurality of times; Based on the first product, a target detection angle reference value corresponding to the first time is determined among the multiple target detection angles; Based on the first time and the angular velocity of the turntable, determine the turntable angle corresponding to the first time; Based on the target detection angle reference value corresponding to the first time and the turntable angle corresponding to the first time, the detection angle error reference value corresponding to the first time is determined.

4. The method according to claim 2, characterized in that, The step of determining the target detection angle error corresponding to the initial target detection angle by performing linear interpolation calculation based on the initial target detection angle, the target detection angle range, and the detection angle error range includes: Calculate the first difference between the initial detection angle and the first target detection angle reference value, where the first target detection angle reference value represents the left endpoint of the target detection angle interval and the second target detection angle reference value represents the right endpoint of the target detection angle interval; Calculate the second difference between the second target detection angle reference value and the first target detection angle reference value; Calculate the second ratio of the first difference to the second difference; Calculate the third difference between the second detection angle error reference value and the first detection angle error reference value, where the first detection angle error reference value represents the left endpoint of the detection angle error interval and the second detection angle error reference value represents the right endpoint of the detection angle error interval. Calculate the second product of the second ratio and the third difference; The sum of the second product and the first detection angle error reference value is calculated to determine the target detection angle error.

5. The method according to claim 1, characterized in that, Based on the angle measurement range, N preset detection angles are determined. The millimeter-wave radar includes M channels, each channel corresponding to an antenna phase center spacing and an initial phase difference. The step of determining the steering vector based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles includes: For the i-th preset detection angle and the m-th channel, based on the antenna phase center spacing and initial phase difference corresponding to the m-th channel, and the i-th preset detection angle, determine the element in the i-th row and m-th column of the guide vector.

6. The method according to claim 5, characterized in that, The step of determining the target detection angle of the target to be detected from multiple preset detection angles based on the guide vector and the phase information includes: The product matrix is ​​obtained by multiplying the steering vector and the phase information; Determine the integers in the product matrix; The preset detection angle corresponding to the integer in the guide vector is determined as the target detection angle.

7. The method according to claim 1, characterized in that, The millimeter-wave radar includes multiple channels, each channel corresponding to a phase information; The step of fitting based on multiple phase information and the turntable angle corresponding to the phase information to determine the antenna phase center spacing and initial phase difference includes: A reference channel and a target channel are determined, and the phase difference is determined based on the phase information of the reference channel and the phase information of the target channel; A linear function relationship is determined by fitting the results of multiple phase differences and the sine value of the turntable angle corresponding to each phase difference. The intercept of the linear function relationship is determined as the initial phase difference of the target channel; Calculate the third product between the slope of the linear function and the wavelength of the millimeter-wave radar, and calculate the ratio of the third product to 2π to obtain the antenna phase center spacing.

8. A device for improving the angle measurement accuracy of millimeter-wave radar, characterized in that, The device includes: The detection unit is used to respond to the turntable driving the millimeter-wave radar to rotate at a constant speed, control the millimeter-wave radar to detect the target to be detected at preset time intervals, and acquire multiple echo data of the millimeter-wave radar. The target to be detected is simulated using an echo simulator, and the rotation range is the angle measurement range of the millimeter-wave radar. The processing unit is used to process the echo data to obtain the phase information of the millimeter-wave radar; A fitting unit is used to perform fitting based on multiple phase information and the turntable angle corresponding to the phase information to determine the antenna phase center spacing and the initial phase difference; The first determining unit is used to determine the guiding vector based on the antenna phase center spacing, the initial phase difference, and multiple preset detection angles; The second determining unit is used to determine the target detection angle of the target to be detected from multiple preset detection angles based on the guiding vector and the phase information. The third determining unit is used to determine the detection angle error based on the target detection angle and the turntable angle corresponding to the target detection angle, so as to compensate for the angle of other targets detected by the millimeter-wave radar based on the detection angle error.

9. An electronic device, characterized in that, The device includes: a memory and a processor; The memory is used to store the relevant program code; The processor is used to call the program code to execute the method for improving the angle measurement accuracy of millimeter-wave radar as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program for performing the method for improving the angle measurement accuracy of millimeter-wave radar as described in any one of claims 1 to 7.

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