Radar antenna processing method

Abstract

The invention relates to the technical field of radar antenna processing, in particular to a radar antenna processing method. The method comprises the following steps: acquiring a design value of an antenna size, and processing based on the design value to obtain a PCB sample; performing size data measurement on the PCB sample to obtain an actual measurement value of the PCB sample, and performing size deviation value division based on the design value and the actual measurement value to obtain a plurality of size deviation value groups; pasting the PCB samples and assembling the PCB samples into a plurality of radars to be tested; testing the plurality of radars, and determining a dimensional deviation value corresponding to the qualified radars based on a test result; and determining a corresponding antenna size based on the size deviation value, and processing to obtain a target antenna PCB based on the antenna size.

Description

Technical Field

[0001] The present invention relates to the technical field of radar antennas, and in particular to a method for processing radar antennas. Background Art

[0002] In the current antenna design of vehicle-mounted millimeter-wave radar, microstrip antenna is indeed a widely used antenna type. This is mainly due to the characteristics of microstrip antenna such as small size, high integration, and wide relative bandwidth, which make microstrip antenna very suitable for vehicle-mounted millimeter-wave radar systems. Generally, microstrip antennas are produced by third-party PCB processing plants. After the factory completes the antenna processing, it uses a two-dimensional imager to measure the actual size of the antenna, but due to the T-shaped effect of PCB processing and inconsistent measurement point selection, the measurement error is large. In addition, due to the large amount of antenna size chain data and the large number of PCBs, data processing is difficult, which increases the cost of PCB board making. If the radar PCB returned from the PCB board factory is to be re-inspected, it will also increase the cost of manpower, equipment and time, and there may be errors between the re-inspection results and the measurement results of the board factory. Therefore, how to provide a high-precision radar antenna manufacturing method is a problem that needs to be solved urgently. Summary of the invention

[0003] The present invention provides a radar antenna processing method, and determines an economical and efficient antenna processing accuracy range through experiments and tests to achieve stable production of radar products and improve production yield.

[0004] In a first aspect, the present application provides a method for processing a radar antenna, the method comprising: obtaining a design value of the antenna size, and processing multiple PCB board samples based on the design value; measuring the size data of the multiple PCB board samples to obtain the measured values ​​of the PCB board samples, and dividing the size deviation based on the design value and the measured value to obtain multiple size deviation groups; patching the PCB board samples and assembling them into multiple radars to be tested; testing the multiple radars, and determining the size deviation groups corresponding to the qualified radars based on the test results.

[0005] In a possible implementation of the first aspect, the processing method further includes: determining a corresponding antenna size based on the size deviation grouping, and processing a target antenna PCB board based on the antenna size.

[0006] In a possible implementation of the first aspect, dimension data of a PCB board sample is measured to obtain a measured value of the PCB board sample, and deviations are divided based on design values ​​and measured values ​​to obtain multiple dimension deviation groups, including: measuring the dimension of a PCB board in a first direction of the PCB board in the PCB board sample to obtain a measured value of the PCB board sample.

[0007] In a possible implementation of the first aspect, a design value of the antenna size is obtained, and multiple PCB board samples are processed based on the design value, which also includes: based on the design value, simulating to obtain theoretical size deviation grouping; based on the theoretical deviation grouping, finding a third-party processing factory to process and obtain multiple PCB board samples.

[0008] In a possible implementation of the first aspect, testing multiple radars includes: performing a directional pattern test on each radar to be tested in a microwave darkroom that meets the first condition, and obtaining signal data of the radar to be tested at each test angle.

[0009] In a possible implementation of the first aspect, in a microwave darkroom that meets the first condition, performing a directional pattern test on each radar to be tested includes: installing each radar to be tested on a test turntable;

[0010] In the first test angle range, the test turntable is rotated with the first angle as a step length, and signal data in the corresponding direction is collected.

[0011] In a possible implementation of the first aspect, based on the test results, a deviation grouping that meets the radar performance requirements is determined, including: based on the signal data, drawing a corresponding directional diagram, determining a corresponding peak on the directional diagram, and based on a first preset angle, determining an angle deviation of the test angle corresponding to the peak; when the angle deviation is less than the preset angle deviation, the radar to be tested is a qualified radar; based on the size deviation corresponding to the qualified radar, a corresponding size deviation grouping is determined.

[0012] In a possible implementation of the first aspect, the first test angle includes an azimuth angle and an elevation angle; wherein the test angle range of the azimuth angle is ±50°; the test angle range of the elevation angle is ±10°; and the first angle is 1°.

[0013] In a possible implementation of the first aspect, the first preset angle is a theoretical angle corresponding to the peak on the direction diagram, where the theoretical angle is 0°. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 According to an embodiment of the present application, a schematic flow chart of a method for manufacturing a radar antenna is shown.

[0016] Figure 2According to an embodiment of the present application, a schematic diagram of the measurement position of a PCB board of an arbitrary branch antenna is shown.

[0017] Figure 3 According to an embodiment of the present application, a schematic diagram of a testing process of a radar to be tested in a microwave darkroom is shown.

[0018] Figure 4 According to an embodiment of the present application, a curve diagram of the test results of a qualified radar is shown.

[0019] Figure 5 According to an embodiment of the present application, a curve diagram of the test results of an unqualified radar is shown. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0021] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0022] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0023] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0024] As mentioned above, due to the large amount of antenna size chain data and the large number of PCBs, data processing is difficult, which increases the cost of PCB board making. If the radar PCB returned from the PCB board factory is to be re-inspected, it will also increase the manpower, equipment and time costs, and there may be errors between the re-inspection results and the measurement results of the board factory. In order to solve the above problems, the present application provides a method for making a radar antenna. First, the theoretical value of the antenna size is determined according to the simulation data, and the measured values ​​of all antenna sizes in the first batch of trial-produced PCBs are obtained. Based on the theoretical value and the measured value, the deviation of the antenna size is obtained, and the deviation is grouped; secondly, these PCB patches are assembled into a radar machine. Then, the directional diagram of the radar machine is tested in a microwave darkroom that meets the far-field conditions, and the test results are analyzed using a MATLAB script. Next, an acceptable deviation group is determined based on the test results, that is, the antenna size accuracy within the deviation range has an acceptable impact on the radar performance. Finally, this information is fed back to the PCB board factory, requiring its manufacturing accuracy to meet the process requirements to ensure process stability and mass production.

[0025] Thus, based on the manufacturing method of the radar antenna provided by the present application, the deviation of the manufactured antenna size is within an acceptable range, that is, the impact on the radar performance is acceptable. In addition, there is no need for the radar company to conduct a re-inspection, saving the manpower, material resources and time costs required for the relevant measurements.

[0026] Combine the following Figure 1 The specific implementation process of the manufacturing method of a radar antenna provided in this application is described in detail. Figure 1 The specific steps are as follows:

[0027] S101: Obtain design values ​​of antenna dimensions, and obtain multiple PCB board samples based on the design values.

[0028] Exemplarily, the radar antenna simulation can be performed through simulation software to obtain the theoretical value of the radar antenna size, also known as the design value. The design value of the above radar antenna size is given to a third-party PCB factory. The third-party PCB factory produces a batch of PCB boards as templates based on the above design values, i.e., PCB board samples. In some embodiments, according to the design value of the antenna size, multiple theoretical size deviations that meet the radar performance can be simulated, such as 10μm, 15μm, 20μm, 25μm, etc., and based on the feasible theoretical size deviation grouping, the corresponding processing accuracy (also known as the maximum size deviation) is within the feasible theoretical deviation grouping range. The third-party processing factory is found, which can also reduce the processing cost.

[0029] S102: Dimension data of the PCB sample is measured to obtain a measured value of the PCB sample, and dimension deviations are divided based on the design value and the measured value to obtain a plurality of dimension deviation groups.

[0030] It is understandable that due to process errors when third-party PCB factories make PCB boards, the size of the manufactured PCB boards deviates from the design value. Therefore, it is necessary to first measure the size of all PCB boards in the PCB board sample, that is, to obtain the measured value of the PCB board sample. Then, based on the difference between the design value and the measured value, the deviation is divided to obtain multiple deviation groupings. In some embodiments, the above deviations can be divided into A1, A2, A3, and A4. Among them, the relationship between A1, A2, A3, and A4 is A1>A2>A3>A4. Reference Figure 2 As shown, Figure 2 is a schematic diagram of any antenna branch in the radar antenna. Figure 2 It can be known that each antenna in the radar includes two branches, namely the first branch and the second branch, and the order and corresponding size of the PCB boards corresponding to the first branch and the second branch are the same, so it is only necessary to measure the size of the PCB board of either the first branch or the second branch in the first direction, that is, the width of the PCB board. For example, the width of PCB board 1, namely W1 in the figure. The sizes of other PCB boards in the figure in the first direction are similar to the measurement method of PCB board 1, and are not enumerated here. Table 1 is some design value data examples provided by this application. It can be understood that the measured values ​​obtained by all the measurements of the sizes of the PCB board on the antenna, as well as the actual size deviations obtained according to the design values ​​and the measured values ​​are filled in Table 1. It should be noted that the design values ​​in Table 1 are only used as examples and do not limit the design values ​​of this application.

[0031] Table 1

[0032]

[0033]

[0034] S103: PCB board samples are mounted and assembled into multiple radars to be tested.

[0035] Radar assembly: Radar assembly usually involves multiple key components, including the bottom shell, heat sink, PCBA (Printed Circuit Board Assembly) and antenna cover. The following is a detailed description of these components and their assembly process: The bottom shell serves as the installation base for other components. Since the radar generates a lot of heat during operation, a heat sink is required to effectively dissipate the heat to maintain the normal operating temperature of the radar. Heat sinks can be, for example, heat sinks, heat sinks, and heat pipes. These heat sinks are usually made of materials with good thermal conductivity (such as aluminum or copper). PCBA is the core component of the radar, usually including antenna structure, transmitter, receiver, duplexer, waveguide and other parts, responsible for generating, transmitting and receiving radio frequency signals. The PCB board sample in this application can be used for component patching to form a PCBA. The antenna cover is used to protect the antenna from the influence of the external environment, such as wind, rain, dust and impact. At the same time, it can also reduce the energy loss of the radar to a certain extent.

[0036] The specific assembly process of the radar unit is as follows: First, prepare all the necessary components and tools, including the bottom shell, heat sink, PCBA, radome, and auxiliary materials such as screws and connectors. Further, place the bottom shell on the assembly platform as the installation basis for other components. According to the design requirements, install heat sinks such as heat sinks, cooling fans, etc. on the bottom shell. Place the PCBA at the designated position on the bottom shell and connect it to the bottom shell through connectors or welding. At the same time, ensure that all electronic components and circuits on the PCBA are correct. Finally, install the radome around the antenna on the PCBA and connect it to the bottom shell through screws or other fixing methods. During the installation process, maintain an appropriate gap between the radome and the antenna.

[0037] S104: Testing multiple radars, and determining size deviation groups corresponding to qualified radars based on the test results.

[0038] Exemplarily, radiation pattern tests are performed on multiple radars to be tested in a radar microwave anechoic chamber that meets far-field conditions. Specifically, in the radar microwave anechoic chamber, the design of the chamber size needs to meet the first condition of the radar to ensure the accuracy and reliability of the test results. In this embodiment, the first condition is the far-field condition. The far-field condition means that the test distance between the antenna under test and the reference antenna (or source antenna) is far enough so that the electromagnetic wave exhibits the characteristics of a plane wave during propagation, thereby being able to accurately simulate the working conditions of the radar in the actual application environment.

[0039] For the specific test process, please refer to Figure 3 ,like Figure 3As shown, the radar to be tested is installed on a test rotating table, and the rotating table is controlled to rotate by a controller, and a set of signal data is collected each time it rotates. For example, within the first test angle range, the test turntable is rotated with a first angle as a step length, and signal data in the corresponding direction is collected. The first test angle includes azimuth and elevation. For example, within the range of azimuth ±50° and elevation ±10°, the rotating table is rotated with 1° as a step length (step), and a set of signal data, such as signal gain, is collected each time it rotates. Furthermore, MATLAB analyzes the signal data based on the collected signal data through a preset algorithm script and draws a directional diagram.

[0040] The specific analysis process, for example, can be: collect test data, including azimuth data and elevation data. Further, evaluate and analyze the test data, and plot the test data of all channels into a multi-channel directional diagram, through which the symmetry of the directional diagram of the radar to be tested can be determined. Then evaluate and analyze the test data of each transceiver channel of the test data, and plot the directional diagram of each single transceiver channel. For specific directional diagrams, please refer to Figure 4 or Figure 5 And the following Figure 4 or Figure 5 The relevant description in will not be repeated here. Finally, the current radar under test is analyzed according to different directional patterns to see whether it meets the radar performance requirements. It can be understood that the directional pattern with frequency deviation has obvious differences in the degree of discreteness of the left and right channels of the directional pattern.

[0041] It can be understood that the problem caused by large deviations in antenna size is mainly reflected in the deviation of the optimal operating frequency band of the radar. For example, the design operating frequency band of the radar antenna is 76.1GHz-76.9GHz. When there is a size deviation, the operating frequency band will be deviated to 77.1GHz-77.9GHz. The angle deviation can be analyzed by the symmetry of the elevation pattern and the symmetry of the azimuth pattern to determine whether the corresponding antenna meets the radar performance requirements. That is, the test angle corresponding to the peak value is determined on each pattern. When the test angle corresponding to the peak value is degrees, the radar to be tested is a qualified radar. It should be understood that when the radar to be tested meets the radar performance requirements, the angle corresponding to the peak value on its pattern is zero degrees. Reference Figure 4 , Figure 4 A-1 is the comprehensive directional diagram of each channel when the peak corresponds to an angle of 0° within the range of pitch angles, which can more intuitively judge the symmetry of the directional diagram, and A-2 is the azimuth diagram of a single channel. Similarly, B-1 is the comprehensive directional diagram of each channel when the peak corresponds to an angle of 0° within the range of azimuth angles, and B-2 is the azimuth diagram of a single channel. Figure 4It can be seen that when the peak corresponds to an angle of 0°, the consistency of each channel is good and the symmetry is also good, which meets the radar performance requirements. The corresponding radar under test is a qualified radar. Figure 5 ,in, Figure 5 The antenna processing size is too small - 30um, Figure 5 C-1 is the comprehensive radiation pattern of each channel within the range of elevation angles when the peak corresponds to an angle of -2°, and C-2 is the azimuth pattern of a single channel. D-1 is the comprehensive radiation pattern of each channel within the range of azimuth angles when the peak corresponds to an angle of -2°, and D-2 is the azimuth pattern of a single channel. The symmetry of each channel is poor, and it is comprehensively judged that the performance of this group of antennas does not meet the performance requirements of the radar. It can be seen that when the antenna size is smaller than -30um, it has little effect on the symmetry of the radiation pattern, and the corresponding angle of the peak is also 0°, but it has a greater impact on the consistency of the radiation pattern, that is, by Figure 4 A-2 and Figure 5 It can be seen from C-2 in the figure that there is a frequency deviation directional diagram, and the degree of discreteness of the left and right channels of the directional diagram is obviously different. Therefore, by judging the relationship between the peak deviation amount and the preset peak deviation amount, it can be judged whether the radar under test meets the radar performance requirements. When the radar under test meets the radar performance requirements, the radar under test is a qualified radar.

[0042] It can be understood that the processing method of the radar antenna provided in the present application also includes the following steps: determining the corresponding antenna size based on the size deviation, and processing the target antenna PCB board based on the antenna size.

[0043] It can be understood that based on the qualified radars that meet the radar performance in the radar to be tested in step S105, and based on the above qualified radars, the corresponding PCB board size is determined, and the PCB board deviation range that can meet the radar performance, that is, the qualified deviation range, is determined. Based on the qualified deviation range, a third-party PCB factory with a processing accuracy (also known as the maximum deviation) within the qualified deviation range is found, and the board factory can start mass production.

[0044] In this way, based on the radar antenna processing method provided in this application, an economical and efficient antenna processing accuracy range is determined through experiments and tests to achieve stable production of radar products and improve production yield.

[0045] It should be noted that, for the sake of convenience of description, the aforementioned method embodiments are all expressed as a series of action combinations, but those skilled in the art should know that the present invention is not limited to the described order of actions, because according to the present invention, certain steps can be performed in other orders or simultaneously.

[0046] In summary, although the present application has been disclosed as above with preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Ordinary technicians in this field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A method for processing a radar antenna, characterized in that: The method comprises: Obtaining design values ​​of antenna dimensions, and processing and obtaining a plurality of PCB board samples based on the design values; Measuring the dimension data of the plurality of PCB board samples to obtain measured values ​​of the PCB board samples, and dividing the dimension deviation amounts based on the design values ​​and the measured values ​​to obtain a plurality of dimension deviation amount groups; The PCB board samples are mounted and assembled into a plurality of radars to be tested; the plurality of radars are tested, and based on the test results, the size deviation amount grouping corresponding to the qualified radars is determined.

2. The processing method according to claim 1, characterized in that: The processing method further includes: determining the corresponding antenna size based on the size deviation grouping, and processing a target antenna PCB board based on the antenna size.

3. The processing method according to claim 1, characterized in that: The PCB sample is measured for size data to obtain a measured value of the PCB sample, and deviations are divided based on the design value and the measured value to obtain a plurality of size deviation groups, including: The dimension of the PCB board sample in the first direction is measured to obtain the actual measured value of the PCB board sample.

4. The method according to claim 1, characterized in that: The method further comprises: obtaining a design value of the antenna size, and processing a plurality of PCB board samples based on the design value, and further comprising: Based on the design value, a grouping of theoretical size deviations is obtained by simulation; Based on the theoretical size deviation grouping, a third-party processing factory is found to process and obtain multiple PCB board samples.

5. The processing method according to claim 1, characterized in that: The testing of the multiple radars includes: performing a directional pattern test on each of the radars to be tested in a microwave darkroom that meets the first condition, and obtaining signal data of the radar to be tested at each test angle.

6. The processing method according to claim 5, characterized in that: The step of performing a directional pattern test on each of the radars to be tested in a microwave darkroom that meets the first condition comprises: Mounting each of the radars to be tested on a test turntable; In the first test angle range, the test turntable is rotated with the first angle as a step length, and signal data in the corresponding direction is collected.

7. The processing method according to claim 6, characterized in that: The step of determining the deviation grouping that meets the radar performance requirements based on the test results includes: Based on the signal data, a corresponding directional diagram is drawn, a corresponding peak value is determined on the directional diagram, and an angle deviation of a test angle corresponding to the peak value is determined based on a first preset angle; when the angle deviation is less than the preset angle deviation, the radar to be tested is a qualified radar; Based on the size deviations corresponding to the qualified radars, corresponding size deviation groups are determined.

8. The processing method according to claim 6, characterized in that: The first test angle includes an azimuth angle and a pitch angle; wherein the test angle range of the azimuth angle is ±50°; the test angle range of the pitch angle is ±10°; and the first angle is 1°.

9. The processing method according to claim 7, characterized in that: The first preset angle is a theoretical angle corresponding to the peak on the radiation pattern, wherein the theoretical angle is 0°.

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