CN-122017752-A - Antenna test method and system for 4D millimeter wave radar

Abstract

The invention provides an antenna test method and system of a 4D millimeter wave radar, which are characterized in that a radar echo simulator is used for generating a simulation target with preset distance and preset non-zero speed, point cloud data of the radar to be tested are collected under a plurality of rotation angles, and screening processing is carried out on the data in the two dimensions of the distance and the speed at the same time, so that a simulation target point is accurately identified from static environment clutter, complex frequency spectrum data of each channel corresponding to the target point is extracted, and the gain and phase characteristics of the antenna are determined according to the change of the complex frequency spectrum data along with the rotation angle. According to the invention, a traditional microwave darkroom is not required, and the environmental clutter interference is effectively inhibited by a signal processing means, so that the cost and the space requirement of a calibration system are obviously reduced, the portability and the testing flexibility are improved, and the accuracy of a calibration result is ensured.

Inventors

• DAI CHUNYANG
• WU CHAO
• WANG JINGWEI

Assignees

• 深圳电目科技有限公司

Dates

Publication Date

20260512

Application Date

20251009

Claims (10)

1. 1. The antenna test method of the 4D millimeter wave radar is characterized by comprising the following steps of: S1, setting preset parameters of a radar echo simulator, and presetting a simulation target with a target distance (R target ) and a non-zero target speed (V target ); S2, transmitting signals, namely transmitting signals to an antenna of the radar to be detected by a radar echo simulator; S3, acquiring point cloud data, namely enabling the radar to be tested to rotate according to a specified rotation angle, and acquiring the point cloud data of the radar under the rotation angle, wherein the point cloud data comprises a measurement distance and a measurement speed of each detection point and complex frequency spectrum data of each channel; S4, filtering point cloud data based on a preset target distance and preset non-zero target speed data to identify a target point corresponding to the simulation target; S5, determining the antenna characteristics, repeatedly executing the step S3 and the step S4 to obtain point cloud data of the antenna under a plurality of rotation angles, extracting complex spectrum data of each channel corresponding to the target point, and determining the antenna characteristics based on the complex spectrum data extracted under the plurality of rotation angles.
2. 2. The method for testing the antenna of the 4D millimeter wave radar according to claim 1, wherein the filtering step in the step S4 comprises the steps of: Defining a distance window and a speed window, and screening out detection points of which the measured distance and the measured speed fall into corresponding windows, wherein the distance window is [ R target -kδ R ,R target +kδ R ], the speed window is [ V target -kδ v ,V target +kδ v ], k is a constant, delta R is the distance resolution of the radar, and delta v is the speed resolution of the radar.
3. 3. The method according to claim 2, wherein the step of identifying a target point in the step S4 further comprises selecting a point with a maximum signal strength among the screened detection points as the target point, wherein the signal strength is determined by a sum of modes of complex spectrum data of the channels.
4. 4. The method for testing an antenna of a 4D millimeter wave radar according to claim 1, wherein in the step S3, the 4D millimeter wave radar is mounted on a turntable, and the plurality of rotation angles are switched by controlling rotation of the turntable.
5. 5. The method for testing an antenna of a 4D millimeter wave radar according to claim 1, wherein said determining an antenna characteristic step comprises generating an antenna gain map by plotting a modulus of said complex spectrum data as a function of rotation angle.
6. 6. The method for testing an antenna of a 4D millimeter wave radar according to claim 1, wherein the step of determining the antenna characteristic comprises generating a spatial phase map by plotting the phase of the complex spectrum data as a function of the rotation angle.
7. 7. The method for testing an antenna of a 4D millimeter wave radar according to claim 6, wherein whether a linear relationship exists between the phase of the complex spectrum data and the sine value of the rotation angle is verified by analyzing the space phase diagram to verify the accuracy of antenna calibration.
8. 8. An antenna detection system for a 4D millimeter wave radar, comprising: a radar to be detected; The turntable is used for placing the radar to be tested and driving the radar to rotate; the radar echo simulator is used for transmitting analog signals to an antenna of the radar to be tested; a master control machine connected to the radar to be tested, the turntable and the radar echo simulator, the master control machine being capable of performing the method according to any one of claims 1 to 7.
9. 9. The method for testing an antenna of a 4D millimeter wave radar according to claim 8, wherein the main controller is capable of sending a rotation command to the turntable to control a rotation angle and receiving point cloud data from the radar to be tested.
10. 10. The method for testing an antenna of a 4D millimeter wave radar according to claim 8, wherein a predetermined spatial distance is maintained between the radar echo simulator and a radar to be tested mounted on the turntable.

Description

Antenna test method and system for 4D millimeter wave radar Technical Field The invention relates to the technical field of radar testing, in particular to an antenna testing method and system of a 4D millimeter wave radar. Background The 4D millimeter wave radar can provide distance, speed, horizontal angle and pitch angle information of a target at the same time, is widely applied to the fields of automatic driving, intelligent traffic, security monitoring and the like, and the performance of the radar antenna, particularly the gain pattern and the phase consistency among all channels, directly determines the detection precision and reliability of the radar. Therefore, in the research and development and production process of the radar, the precise calibration of the antenna is an important link. The traditional 4D millimeter wave radar antenna calibration method is usually carried out in a microwave darkroom. The scheme mainly depends on a microwave darkroom for shielding external electromagnetic signal interference and absorbing radar signal reflection so as to simulate an environment similar to free space, a corner reflector serving as an ideal point target source, a high-precision turntable for bearing the radar to be detected and accurately changing the orientation, and an upper computer for controlling the turntable to rotate and collecting and processing radar data. During testing, the corner reflector is placed in the deep part of the darkroom, and the radar to be tested is fixed on the turntable, so that the normal line of the antenna is aligned with the corner reflector. By rotating the turntable, the echo signals of the corner reflectors received by the radar at different angles can be measured, so that an antenna pattern is drawn and the phase is calibrated. However, this conventional solution based on microwave darkroom has a number of inherent drawbacks: 1. The microwave darkroom has high space and cost requirements, and the length of the microwave darkroom is usually required to be more than several times of the distance resolution of the radar so that the microwave darkroom occupies a large area and has high construction and maintenance cost. 2. Environmental and health problems-wave absorbing materials (such as pyramid sponges) laid on the inner wall of a darkroom can release peculiar smell in long-term use, and form potential threats to the health of test personnel. 3. The portability is poor, the microwave darkroom is a large-scale fixed facility and cannot move, the testing place and flexibility are limited, and the field or outfield test is inconvenient to carry out. These drawbacks limit the efficiency and accessibility of the radar antenna calibration work, increasing the development and production costs of the radar product. Disclosure of Invention In view of the above drawbacks of the prior art, the present invention is directed to a method and a system for testing an antenna of a 4D millimeter wave radar, which are used for solving the problem that the prior art relies on a large, expensive and inconvenient microwave darkroom for antenna testing. To achieve the above and other related objects, the present invention provides an antenna testing method for a 4D millimeter wave radar, comprising the steps of: s1, setting preset parameters of a radar echo simulator, and presetting a target distance and a simulation target with a preset non-zero target speed; S2, transmitting signals, namely transmitting signals to an antenna of the radar to be detected by a radar echo simulator; s3, acquiring point cloud data, namely enabling the radar to be tested to rotate according to a specified rotation angle, and acquiring the point cloud data of the radar under a plurality of rotation angles, wherein the point cloud data comprises a measurement distance and a measurement speed of each detection point and complex frequency spectrum data of each channel; S4, filtering point cloud data based on a preset target distance and preset non-zero target speed data to identify a target point corresponding to the simulation target; s5, determining antenna characteristics, extracting complex spectrum data of each channel corresponding to the target point, and determining the antenna characteristics based on the complex spectrum data extracted under a plurality of rotation angles. By adopting the technical scheme, the traditional combination of the microwave darkroom and the corner reflector is replaced by the radar echo simulator, the simulation target generated by the radar echo simulator is obviously distinguished from surrounding static clutter (such as walls, furniture and the like) in the Doppler dimension, then the point cloud data of a plurality of different rotation angles are tested, the point cloud data collected by each angle are screened, a unique target point generated by the echo simulator is accurately separated and identified from a background environment containing a large number of static c