Traffic radar pitch angle installation error calibration method and device and storage medium

Abstract

The application discloses a traffic radar pitch angle installation error calibration method and device and a storage medium. The method comprises the following steps: changing the frequency of a traffic radar according to a preset strategy in a preset frequency range; sequentially obtaining echo signal energy values of a preset target under different frequencies; if the obtained echo signal energy values meet preset conditions, determining the frequency corresponding to the maximum echo signal energy value as the working frequency of the traffic radar, so as to calibrate the traffic radar pitch angle installation error; wherein the preset target is arranged on the ground, and the distance between the preset target and the projection point of the traffic radar in the horizontal direction of the ground is the length of the horizontal projection of the central beam of the traffic radar when the traffic radar is installed at an expected pitch angle. The traffic radar pitch angle installation error calibration method and device and the storage medium not only calibrate the traffic radar pitch angle installation error at a low cost, but also solve the problem that the pitch angle installation error affects the detection range and the capture rate of the traffic radar.

Description

Technical Field

[0001] This application relates to the field of traffic radar communication technology, and more particularly to a method, device and storage medium for calibrating the elevation angle installation error of traffic radar. Background Technology

[0002] Traditional video is easily affected by environmental factors such as strong light and rain or snow, which greatly limits its application in the field of intelligent transportation. Millimeter-wave traffic radar, on the other hand, plays an irreplaceable role in intelligent transportation systems due to its advantages such as long detection range, high speed measurement accuracy, and less susceptibility to weather conditions.

[0003] In practical applications, traffic radars are typically installed on L-shaped poles along the roadside, with pole heights ranging from 6 to 8 meters. Traditionally, the normal direction of a traffic radar is designed to have the strongest antenna gain. To ensure road coverage, traffic radars are typically installed at a downward tilt angle on the pole. However, deviations in the elevation angle of the traffic radar installation can significantly impact its target detection coverage and long-range target acquisition rate. Based on the current application requirements of millimeter-wave traffic radars in major scenarios such as urban roads and elevated / highway ramp entrances and exits, the radar is required to cover a target vehicle detection range of 20m–230m. Assuming the L-shaped pole height for installing the traffic radar is 8 meters, and considering that antenna gain is inversely proportional to the field of view (FOV) angle in practical applications, to ensure the long-range detection capability of the traffic radar, the antenna elevation direction 3dB FOV is designed to be ±3° (e.g., ...). Figure 1 β1 in the middle), 10dB FOV is ±16° (e.g. Figure 2 (β1 in the text) requires the traffic radar to be tilted down by 5° (e.g., β1 in the text). Figure 1 , Figure 2 (β0 in the original text). Therefore, the projected length of the traffic radar's center beam in the horizontal direction is approximately 90m. A 3dB antenna can cover a distance of about 230m in the horizontal direction, while a 10dB antenna can cover a distance of about 20m at close range. If the traffic radar's elevation angle deviates by 2 degrees, becoming 7° downwards, the projected length of the traffic radar's center beam in the horizontal direction will be approximately 65m. The 3dB antenna's coverage distance in the horizontal direction will only reach 115m. This will inevitably lead to a low long-range target acquisition rate for the traffic radar, a fact that has been verified in practical applications.

[0004] Currently, electronic sensors can be used to solve the problem of installation angle deviation of traffic radar. However, traffic radar is quite different from car radar. It is rare for the installation angle of traffic radar to change due to bumps, collisions, etc. There is no need to monitor the installation angle of traffic radar in real time. Moreover, the closed-loop control system of sensor + motor + controller will inevitably result in high equipment cost and large size.

[0005] The solution of using software algorithms to calculate the offset angle of traffic radar installation by using specific targets or the surrounding environment, and then using this offset angle as a software compensation parameter for the angle detection results of traffic radar, only compensates for the angle measurement error. It cannot change the direction of the traffic radar antenna beam, and cannot solve the problem that the installation deviation in the elevation direction affects the detection range and acquisition rate of traffic radar. Summary of the Invention

[0006] This application provides a method, device, and storage medium for calibrating the elevation angle installation error of a traffic radar. It not only calibrates the elevation angle installation error of a traffic radar at a low cost, but also solves the problem that the elevation angle installation error affects the detection range and acquisition rate of the traffic radar.

[0007] This application provides a method for calibrating the elevation angle installation error of a traffic radar, comprising:

[0008] Change the frequency of the traffic radar within a preset frequency range according to a preset strategy;

[0009] Sequentially acquire the echo signal energy values ​​of the preset target at different frequencies;

[0010] If the obtained echo signal energy value meets the preset conditions, the frequency corresponding to the maximum echo signal energy value is determined as the operating frequency of the traffic radar to calibrate the elevation angle installation error of the traffic radar.

[0011] The preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle.

[0012] In one exemplary embodiment, the preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

[0013] In one exemplary embodiment, the desired pitch angle is determined based on the installation height of the traffic radar and a preset detection range.

[0014] In one exemplary embodiment, the preset conditions include the acquired echo signal energy value increasing from small to large, and then decreasing from large to small again.

[0015] In one exemplary embodiment, the preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar.

[0016] In one exemplary embodiment, determining the preset frequency range based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar includes:

[0017] According to the preset equation, the first wavelength at which the preset maximum calibration angle is calculated is determined, and the first frequency value is determined according to the first wavelength;

[0018] According to the preset equation, the second wavelength at the preset minimum calibration angle is determined, and the second frequency value is determined according to the second wavelength;

[0019] The preset frequency range is the range from the first frequency value to the second frequency value, including the first frequency value and the second frequency value.

[0020] In one exemplary embodiment, the preset equation is as follows:

[0021] ,

[0022] in, This indicates the preset maximum calibration angle or the preset minimum calibration angle. This represents the distance between two adjacent radiating elements of the traffic radar antenna. This indicates the wavelength of millimeter waves in air. This indicates the wavelength of millimeter waves on a dielectric substrate.

[0023] This application provides a traffic radar elevation angle installation error calibration device, comprising:

[0024] The device includes a frequency changing module, an echo signal energy value acquisition module, and a working frequency determination module;

[0025] The frequency changing module is configured to change the frequency of the traffic radar within a preset frequency range according to a preset strategy.

[0026] The echo signal energy value acquisition module is configured to sequentially acquire the echo signal energy values ​​of a preset target at different frequencies; wherein, the preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle;

[0027] The operating frequency determination module is configured to determine the frequency corresponding to the maximum echo signal energy value as the operating frequency of the traffic radar if the acquired echo signal energy value meets the preset conditions, so as to calibrate the elevation angle installation error of the traffic radar.

[0028] In one exemplary embodiment, the preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

[0029] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, performs the following operations:

[0030] Change the frequency of the traffic radar within a preset frequency range according to a preset strategy;

[0031] Sequentially acquire the echo signal energy values ​​of the preset target at different frequencies;

[0032] If the obtained echo signal energy value meets the preset conditions, the frequency corresponding to the maximum echo signal energy value is determined as the operating frequency of the traffic radar to calibrate the elevation angle installation error of the traffic radar.

[0033] The preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle.

[0034] In one exemplary embodiment, the preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

[0035] In one exemplary embodiment, the desired pitch angle is determined based on the installation height of the traffic radar and a preset detection range.

[0036] In one exemplary embodiment, the preset conditions include the acquired echo signal energy value increasing from small to large, and then decreasing from large to small again.

[0037] In one exemplary embodiment, the preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar.

[0038] In one exemplary embodiment, determining the preset frequency range based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar includes:

[0039] According to the preset equation, the first wavelength at which the preset maximum calibration angle is calculated is determined, and the first frequency value is determined according to the first wavelength;

[0040] According to the preset equation, the second wavelength at the preset minimum calibration angle is determined, and the second frequency value is determined according to the second wavelength;

[0041] The preset frequency range is the range from the first frequency value to the second frequency value, including the first frequency value and the second frequency value.

[0042] In one exemplary embodiment, the preset equation is as follows:

[0043] ,

[0044] in, This indicates the preset maximum calibration angle or the preset minimum calibration angle. This represents the distance between two adjacent radiating elements of the traffic radar antenna. This indicates the wavelength of millimeter waves in air. This indicates the wavelength of millimeter waves on a dielectric substrate.

[0045] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0046] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0047] Figure 1 This is a schematic diagram showing the elevation coverage of a 3dB antenna in the prior art.

[0048] Figure 2 This is a schematic diagram of the elevation coverage of a 10dB antenna in the prior art;

[0049] Figure 3 This is a schematic diagram of a traffic radar elevation angle installation error calibration method according to an embodiment of this application;

[0050] Figure 4 This is a flowchart of a traffic radar elevation angle installation error calibration method according to an embodiment of this application;

[0051] Figure 5 This is a schematic diagram of the antenna elevation beam pointing at different frequencies in the prior art;

[0052] Figure 6 This is a schematic diagram illustrating the trend of target energy value changing with antenna frequency during the calibration process according to an embodiment of this application.

[0053] Figure 7 This is a schematic diagram of a traffic radar elevation angle installation error calibration device according to an embodiment of this application. Detailed Implementation

[0054] Figure 3 This is a flowchart of the traffic radar elevation angle installation error calibration method according to an embodiment of this application, as follows: Figure 3 As shown, the traffic radar elevation angle installation error calibration method of this embodiment includes steps S11-S13:

[0055] S11. Change the frequency of the traffic radar within the preset frequency range according to the preset strategy;

[0056] S12. Sequentially acquire the echo signal energy values ​​of the preset target at different frequencies;

[0057] S13. If the obtained echo signal energy value meets the preset conditions, the frequency corresponding to the maximum echo signal energy value is determined as the operating frequency of the traffic radar.

[0058] In one exemplary embodiment, the traffic radar is installed at a preset downtilt angle before its frequency is changed; this downtilt angle must not exceed the designed maximum calibration angle, otherwise calibration will fail. For example, using a coarse angle measuring tool, the downtilt angle is measured to be 5 degrees.

[0059] In one exemplary embodiment, the preset strategy includes changing the frequency from small to large or from large to small, with each change being the same or a different preset step frequency. The step frequency can be set empirically, ensuring both calibration accuracy and calibration time. The step frequency for each frequency change can be the same or different, and can be adjusted as needed.

[0060] In one exemplary embodiment, the preset target is positioned on the ground, and the distance between it and the horizontal projection point of the traffic radar is equal to the length of the horizontal projection of the center beam of the traffic radar when installed at the desired elevation angle. The preset target can be a corner reflector or other highly reflective targets, and there should be no other highly reflective targets around the preset target to avoid affecting the calibration process.

[0061] In one exemplary embodiment, the desired pitch angle is determined based on the installation height of the traffic radar and a preset detection range. The desired pitch angle means that the pitch angle at which the traffic radar is installed is consistent with the preset pitch angle, without error.

[0062] In one exemplary embodiment, the preset conditions include the acquired echo signal energy value increasing from small to large, and then decreasing from large to small again.

[0063] In one exemplary embodiment, the preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar.

[0064] The preset maximum calibration angle is a positive angle value, and the preset minimum calibration angle is a negative angle value; the absolute values ​​of these two can be the same or different.

[0065] In one exemplary embodiment, determining the preset frequency range based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar includes:

[0066] According to the preset equation, the first wavelength at which the preset maximum calibration angle is calculated is determined, and the first frequency value is determined according to the first wavelength;

[0067] According to the preset equation, the second wavelength at the preset minimum calibration angle is determined, and the second frequency value is determined according to the second wavelength;

[0068] The preset frequency range is the range from the first frequency value to the second frequency value, including the first frequency value and the second frequency value.

[0069] In one exemplary embodiment, the frequency is determined based on the wavelength, which can be calculated and verified experimentally.

[0070] In one exemplary embodiment, the preset equation is as follows:

[0071] ,

[0072] in, This indicates the preset maximum calibration angle or the preset minimum calibration angle. This represents the distance between two adjacent radiating elements of the traffic radar antenna. This indicates the wavelength of millimeter waves in air. This indicates the wavelength of millimeter waves on a dielectric substrate.

[0073] This application embodiment compensates for the elevation direction installation error of traffic radar by adjusting the antenna operating frequency to change the direction of the maximum gain of the antenna beam in the elevation direction. This solves the problem that the elevation direction installation error of traffic radar affects the target detection range and acquisition rate, and also saves costs.

[0074] Figure 4 This is a flowchart of the traffic radar elevation angle installation error calibration method according to an embodiment of this application, as follows: Figure 4 As shown, steps S21-S25 are included:

[0075] S21. Traffic radar poles should be installed according to the preset downward tilt angle requirements;

[0076] S22. Place a reflective target at a predetermined distance from the traffic radar in the horizontal direction on the ground;

[0077] S23. Power on the traffic radar and log in to the host computer for debugging.

[0078] S24. Start automatic calibration. The antenna operating frequency changes within a preset frequency range in preset step frequency. At each frequency point, the traffic radar receives the echo of the reflected target and obtains the energy value of the target at different frequencies.

[0079] S25. Record and save the antenna operating frequency at the moment when the echo energy value of the reflected target is at its maximum. This frequency is the subsequent operating frequency of the traffic radar.

[0080] In step S21, the downward tilt angle can be determined by a rough manual judgment method, such as placing the back of the mobile phone against the front panel of the traffic radar and using level software for a simple judgment.

[0081] Millimeter-wave traffic radars typically require long detection ranges (over 200 meters), thus necessitating a relatively small downward tilt angle for installation, generally between 3 and 8 degrees (depending on factors such as detection distance, L-shaped pole height, road slope, and direction of travel). In traffic radar applications, a calibration angle of ±3 degrees is usually sufficient. This is because a large calibration angle corresponds to a wide antenna operating frequency. However, according to electromagnetic wave theory, a significant difference between the antenna's operating frequency and center frequency can lead to beam widening and distortion, and even beam splitting. Therefore, designers must consider the actual antenna dimensions and the specific application scenario when determining the calibration angle, and a maximum calibration angle of ±10 degrees is recommended.

[0082] For example, if the design requires a calibration angle of ±3 degrees, once the antenna dimensions are determined, the value of Lf+Lp (where Lf+Lp is the distance between two adjacent radiating elements of the traffic radar antenna) is also determined. Based on the relationship between the antenna radiation direction angle and the antenna operating frequency, it can be seen that by changing the antenna's operating frequency, the antenna's radiation direction angle can be changed. and The ratio of [value] is used to change the pointing angle of the antenna beam.

[0083] The relationship between the antenna radiation direction angle and the antenna operating frequency is as follows: , The wavelength of millimeter waves in air. The wavelength of the millimeter wave on the dielectric substrate.

[0084] After the antenna PCB is fabricated, the radiation pattern of the traffic radar system needs to be tested to determine the pointing angle of the main lobe at different frequencies. Assuming that the antenna design simulation uses 77GHz as the center operating frequency, meaning the main lobe points towards the traffic radar's normal direction at this frequency, the pointing angle of the main lobe at each frequency within the 76GHz-78GHz range (the operating range of traditional millimeter-wave traffic radar RF chips is 76GHz-81GHz) is tested. Based on the test results, an antenna operating frequency range conforming to a ±3° calibration angle is selected. For example, the final traffic radar will operate within the range of 77GHz-F1 to 77GHz+F2, where the values ​​of F1 and F2 may be different or the same.

[0085] Adjust the antenna operating frequency from 77GHz-F1 to 77GHz+F2. The maximum gain beam pointing in the antenna elevation direction, with 0° (the 77GHz normal direction) as the reference, varies within the range of -θ to +θ. Figure 5 As shown. Here, +θ represents the maximum calibration angle of this invention, and -θ represents the minimum calibration angle. If the actual installation error of the traffic radar exceeds this range, this method cannot be used for calibration.

[0086] In step S22, the preset distance is determined based on the installation height, tilt angle, and operating frequency of the traffic radar. For example, if the pole height is 8 meters, the tilt angle is 5 degrees (without error), and the distance between the antenna normal and the horizontal direction of the ground at 77 GHz frequency is 90 meters, then the preset distance is set to 90 meters. The reflecting target can be a corner reflector or other high-energy reflecting target.

[0087] In step S23, it is necessary to ensure that there are no other highly reflective targets near the ground at a distance of 90 meters to avoid affecting the calibration process.

[0088] In step S24, for example, the antenna operating frequency (i.e. the operating frequency of the traffic radar) varies from 77G-F1 to 77G+F2, with ΔF as the step frequency. At each frequency point, the traffic radar receives the echo of the target at a distance of 90m and obtains the energy value of the target at different frequencies. The selection of the step frequency ΔF should be appropriate, ensuring both calibration accuracy and calibration time.

[0089] In step S25, the antenna operating frequency at the moment when the echo energy value of the reflected target is at its maximum is as follows: Figure 6 The GA point in the diagram. If the traffic radar installation error is within ±θ, the target energy value obtained in this step will change according to a trend of small-large-small (e.g., ...). Figure 6 (As shown).

[0090] This application embodiment compensates for the elevation direction installation error of traffic radar by adjusting the antenna operating frequency to change the direction of the maximum gain of the antenna beam in the elevation direction. This solves the problem that the elevation direction installation error of traffic radar affects the target detection range and acquisition rate, and also saves costs.

[0091] Figure 7 This is a schematic diagram of a traffic radar elevation angle installation error calibration device according to an embodiment of this application, as shown below. Figure 7 As shown, the traffic radar elevation angle installation error calibration device of this embodiment includes a frequency changing module, an echo signal energy value acquisition module, and an operating frequency determination module.

[0092] The frequency changing module is configured to change the frequency of the traffic radar within a preset frequency range according to a preset strategy.

[0093] The echo signal energy value acquisition module is configured to sequentially acquire the echo signal energy values ​​of a preset target at different frequencies; wherein, the preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle;

[0094] The operating frequency determination module is configured to determine the frequency corresponding to the maximum echo signal energy value as the operating frequency of the traffic radar if the acquired echo signal energy value meets the preset conditions, so as to calibrate the elevation angle installation error of the traffic radar.

[0095] In one exemplary embodiment, the preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

[0096] This application embodiment changes the direction of the maximum gain of the antenna beam in the elevation direction by adjusting the antenna operating frequency, thereby compensating for the installation error in the elevation direction of the traffic radar. This solves the problem that the installation error in the elevation direction of the traffic radar affects the target detection range and acquisition rate, and also saves costs.

[0097] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described method for calibrating the installation error of a traffic radar elevation angle.

[0098] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0099] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive scheme as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive schemes to form another unique inventive scheme as defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this application may be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

[0100] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0101] It will be understood by those skilled in the art that all or some of the steps, systems, or apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

Claims

1. A method for calibrating the installation error of a traffic radar elevation angle, characterized in that, The frequency of the traffic radar is changed within a preset frequency range according to a preset strategy; the preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar. Sequentially acquire the echo signal energy values ​​of the preset target at different frequencies; If the obtained echo signal energy value meets the preset conditions, the frequency corresponding to the maximum echo signal energy value is determined as the operating frequency of the traffic radar to calibrate the elevation angle installation error of the traffic radar. The preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle; the desired elevation angle is determined according to the installation height of the traffic radar and the preset detection range.

2. The method as described in claim 1, characterized in that, The preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

3. The method as described in claim 1, characterized in that, The preset conditions include the obtained echo signal energy value increasing from small to large, and then decreasing from large to small.

4. The method as described in claim 1, characterized in that, The preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar, including: According to the preset equation, the first wavelength at which the preset maximum calibration angle is calculated is determined, and the first frequency value is determined according to the first wavelength; According to the preset equation, the second wavelength at the preset minimum calibration angle is determined, and the second frequency value is determined according to the second wavelength; The preset frequency range is the range from the first frequency value to the second frequency value, including the first frequency value and the second frequency value.

5. The method as described in claim 4, characterized in that, The preset equation is as follows: ， in, This indicates the preset maximum calibration angle or the preset minimum calibration angle. This represents the distance between two adjacent radiating elements of the traffic radar antenna. This indicates the wavelength of millimeter waves in air. This indicates the wavelength of millimeter waves on a dielectric substrate.

6. A traffic radar elevation angle installation error calibration device, characterized in that: The device includes a frequency changing module, an echo signal energy value acquisition module, and a working frequency determination module; The frequency changing module is configured to change the frequency of the traffic radar within a preset frequency range according to a preset strategy; the preset frequency range is determined based on the preset maximum calibration angle and preset minimum calibration angle of the traffic radar. The echo signal energy value acquisition module is configured to sequentially acquire the echo signal energy values ​​of a preset target at different frequencies; wherein, the preset target is set on the ground, and the distance between the target and the projection point of the traffic radar in the horizontal direction is the length of the projection of the center beam of the traffic radar in the horizontal direction when it is installed at the desired elevation angle; The operating frequency determination module is configured to determine the frequency corresponding to the maximum echo signal energy value as the operating frequency of the traffic radar if the acquired echo signal energy value meets the preset conditions, so as to calibrate the elevation angle installation error of the traffic radar; the desired elevation angle is determined according to the installation height of the traffic radar and the preset detection range.

7. The apparatus as claimed in claim 6, characterized in that, The preset strategy includes changing the frequency from small to large or from large to small, and changing the same or different preset step frequency each time.

8. A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the traffic radar elevation angle installation error calibration method according to any one of claims 1-5.

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