Method and system for identifying long-distance high-altitude target by common front radar

Abstract

The invention belongs to the technical field of vehicle-mounted radars, and particularly relates to a common front radar long-distance high-altitude target recognition method and system, which remarkably improves the robustness and accuracy of long-distance high-altitude target recognition by optimizing the layout design and multi-dimensional feature fusion in combination with a dynamic speed compensation mechanism. Specifically, the number of pitching array elements is increased to effectively separate main lobe and side lobe signals, multi-frame data filtering is utilized to extract side lobe angle features, and ground mirror image interference is suppressed; establishing a multi-dimensional criterion to distinguish target types by fusing four types of differentiated features; a speed compensation algorithm is introduced to dynamically judge the target motion state in combination with the vehicle speed, and motion ground target interference is effectively eliminated. Finally, the high-altitude target is stably recognized within the distance of 120-200 m, the recognition accuracy is improved by 30% or above, the hardware adaptability is high, and the problems of angle measurement precision bottleneck and height calculation failure caused by channel number limitation in a traditional scheme are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle-mounted radars, and in particular relates to a method and system for recognizing long-range and high-altitude targets using a common front radar. Background Art

[0002] In recent years, with the rapid development of autonomous driving technology, vehicles have placed higher demands on their ability to perceive their surroundings. Accurately identifying distant, high-altitude targets (such as bridges, billboards, and suspended obstacles) is crucial for ensuring driving safety, especially in complex traffic scenarios. However, existing technologies still face the following challenges:

[0003] Pitch angle measurement capabilities are limited. Existing standard automotive millimeter-wave radars (non-imaging radars) are limited by the number of hardware channels and cannot allocate sufficient computing power to the pitch direction, resulting in insufficient pitch angle measurement accuracy. Especially in real road environments, the ground mirror effect can seriously interfere with angle measurement results. The real reflection signal of high-altitude targets and the ground mirror reflection signal are superimposed at the radar receiving end, resulting in alternating main lobe and side lobe signals. The difference in side lobe levels is weak, further reducing the reliability of angle measurement.

[0004] The problem of interference from large targets: For targets with a large height span (such as buses, trucks, etc.), different parts of the targets present multi-angle reflection characteristics under the radar perspective, causing the radar to misjudge that the target distribution range has expanded or the number of targets has increased, exacerbating the complexity of high-altitude target identification.

[0005] Traditional altitude calculation fails. Existing solutions usually calculate target altitude based on pitch angle and distance. However, due to the angle measurement error caused by insufficient number of channels (the error can reach more than ±5°), the calculated altitude value deviates significantly from the actual value, especially in long-distance scenarios above 120 meters. It completely fails and cannot meet the requirements of high-end intelligent driving systems for stable recognition of high-altitude targets (requires recognition distance ≥ 120 meters).

[0006] The risk of confusion with moving targets: High-altitude targets are often stationary objects (such as road signs and overpasses), while ground targets are often moving vehicles or pedestrians. Traditional methods lack effective mechanisms for distinguishing motion states, making it easy to misidentify high-speed ground targets as high-altitude targets, leading to safety hazards.

[0007] In summary, there is an urgent need for a method that can stably identify high-altitude targets at long distances (120 to 200 meters). This method needs to overcome technical difficulties such as ground mirror interference, multi-angle reflection of body targets, insufficient angle measurement accuracy, and confusion of moving targets. Summary of the Invention

[0008] The purpose of the present invention is to provide a method and system for long-range high-altitude target recognition using a common front radar, which realizes stable recognition of high-altitude targets within a range of 120 meters to 200 meters, improves the recognition accuracy by more than 30%, and does not rely on high-density pitch channels or complex imaging algorithms. It has strong hardware adaptability, so as to solve the problems raised in the above-mentioned background technology.

[0009] To achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a method for identifying long-range high-altitude targets by an ordinary front radar, comprising the following steps: setting the number of pitch array elements in the array to be greater than 2 after MIMO; when the target is beyond a distance R, obtaining the absolute value of the angle at which the pitch angle measurement side lobe of multiple frames is located; performing inter-frame filtering on the absolute value of the angle at which the pitch angle measurement side lobe is located; setting an absolute value threshold of the angle at which the pitch angle measurement side lobe is located; and determining that the target is a high-altitude target when the absolute value of the angle at which the side lobe is located is less than the threshold.

[0010] Preferably, when the target is beyond the distance R, the method further includes:

[0011] Obtain the absolute value of the main lobe angle of multi-frame pitch angle measurement, obtain the main lobe ratio of multi-frame pitch angle measurement, and obtain the amplitude value of multi-frame targets;

[0012] performing inter-frame filtering on the absolute value of the angle of the main lobe of the pitch angle measurement, the main-to-side ratio of the pitch angle measurement, and the amplitude value of the target;

[0013] Set the absolute value threshold of the main lobe angle of the pitch angle measurement, the main lobe to side ratio threshold of the pitch angle measurement, and the target amplitude value growth expected curve;

[0014] When the angle of the main lobe of the pitch angle measurement is greater than the absolute value threshold, the main-to-side ratio of the pitch angle measurement is greater than the absolute value threshold, and the amplitude value growth of the target is less than the expected curve, the target is determined to be a high-altitude target.

[0015] Preferably, the inter-frame filtering includes:

[0016] The absolute value of the angle where the main lobe is located, the main-to-side ratio of the pitch angle measurement, the absolute value of the angle where the side lobe is located, and the amplitude value of the target are respectively subjected to inter-frame filtering using Kalman filtering or α-β low-pass filtering.

[0017] Preferably, the determination of the threshold value includes:

[0018] Collect data of long-range high-altitude targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target;

[0019] Collect data of long-range ground targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target;

[0020] After the same filtering process is performed on the four types of data of the high-altitude targets and the ground targets, a dividing value is obtained by comparison and used as a threshold.

[0021] On the other hand, the present invention provides a common front radar long-range high-altitude target recognition system, comprising:

[0022] A processor, configured to execute the above method;

[0023] A memory, used for storing an expected growth curve of a threshold value and a target amplitude value;

[0024] The data acquisition module is used to obtain the absolute value of the main lobe angle of the multi-frame pitch angle measurement, obtain the main lobe to side ratio of the multi-frame pitch angle measurement, and obtain the amplitude value of the multi-frame target;

[0025] A filtering module is used to perform inter-frame filtering on the absolute value of the angle of the main lobe of the pitch angle measurement, the main-to-side ratio of the pitch angle measurement, and the amplitude value of the target;

[0026] A threshold setting module is used to set the absolute value threshold of the main lobe angle of the pitch angle measurement, the main lobe to side ratio threshold of the pitch angle measurement, and the target amplitude value growth expected curve;

[0027] The judgment module is used to judge that the target is a high-altitude target when the angle of the main lobe of the pitch angle measurement is greater than the absolute value threshold, the main-to-side ratio of the pitch angle measurement is greater than the absolute value threshold, and the amplitude value growth of the target is less than the expected curve.

[0028] The speed compensation module is used to compensate the target speed for the speed loss caused by the azimuth angle v / cosθ, where θ is the measured azimuth angle, and add the compensated speed to the vehicle speed. If the result exceeds the set threshold, the high-altitude target is excluded.

[0029] Preferably, the formula for compensating for the speed loss caused by the azimuth angle is: v_compensated=v / cosθ, where v is the speed of the target relative to the radar, and θ is the target azimuth angle.

[0030] Preferably, it also includes: a display module for displaying the determination result and the target amplitude value distance curve.

[0031] Technical effects and advantages of the present invention: Compared with the prior art, the method and system for long-range high-altitude target recognition using a common front radar proposed in the present invention have the following advantages:

[0032] The present invention significantly improves the robustness and accuracy of long-distance high-altitude target recognition by optimizing the array design (the number of pitch elements after MIMO is greater than 2) and multi-dimensional feature fusion (absolute value of mainlobe angle, main-to-side ratio, sidelobe angle, MAG value trend), combined with a dynamic speed compensation mechanism. Specifically, increasing the number of pitch elements effectively separates the mainlobe and sidelobe signals, and using multi-frame data filtering to extract sidelobe angle features, suppressing ground mirror interference; by fusing four types of differentiated features (high-altitude targets have large mainlobe angles, low main-to-side ratios, small sidelobe angles, and slow MAG growth rates, while ground targets have the opposite), a multi-dimensional criterion is established to distinguish target types; a speed compensation algorithm is introduced to dynamically determine the target's motion state in combination with the vehicle's speed, effectively eliminating interference from moving ground targets. Ultimately, stable recognition of high-altitude targets within a distance of 120-200 meters is achieved, with recognition accuracy improved by more than 30%, and strong hardware adaptability, breaking through the angle measurement accuracy bottleneck and altitude calculation failure problems caused by the limited number of channels in traditional solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of a method for identifying long-range, high-altitude targets using a common front radar in Example 1 of the present invention;

[0034] Figure 2 This is a block diagram of a common front radar long-range high-altitude target recognition system in Example 2 of the present invention;

[0035] Figure 3 This is a ground target angle measurement curve diagram in Example 1 of the present invention;

[0036] Figure 4 This is a high-altitude target angle measurement curve diagram in Example 1 of the present invention;

[0037] Figure 5 This is a high-altitude target angle measurement curve diagram in Example 1 of the present invention;

[0038] Figure 6 This is a MAG value distance curve diagram in Example 1 of the present invention. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Example 1

[0041] This embodiment provides Figure 1A method for identifying long-range, high-altitude targets using a conventional front radar includes: setting the number of elevation array elements in the array to be greater than 2 after MIMO; obtaining the absolute value of the angle of the elevation angle sidelobes of multiple frames when the target is beyond a distance R; performing inter-frame filtering on the absolute value of the angle of the elevation angle sidelobes; setting a threshold for the absolute value of the angle of the elevation angle sidelobes; and determining that the target is a high-altitude target when the absolute value of the angle of the sidelobes is less than the threshold. The method specifically includes the following steps:

[0042] In the array layout, the number of elevation array elements is set to be greater than 2 after MIMO, so that there are side lobes in the angle measurement, which makes it easier to obtain the main-to-side ratio information and the absolute value of the angle where the side lobe is located.

[0043] When the target is beyond the distance R(120) meters, the absolute value of the angle of the main lobe, the main-to-side ratio of the pitch angle, the absolute value of the angle of the side lobe, and the amplitude value of the target are all statistically analyzed through multiple frames of data.

[0044] The absolute values ​​of the angles at which the side lobes of the pitch angle measurement are located are subjected to inter-frame filtering respectively; further, the absolute value of the angle at which the main lobe is located, the main-to-side ratio of the pitch angle measurement, the absolute value of the angle at which the side lobes are located, and the amplitude value of the target are subjected to inter-frame filtering respectively using Kalman filtering or α-β low-pass filtering.

[0045] Set the absolute value threshold of the angle where the side lobe of the pitch angle measurement is located, the main-to-side ratio threshold of the pitch angle measurement, the absolute value threshold of the angle where the side lobe is located, and the expected curve of the target amplitude value growth; the threshold settings include:

[0046] Collect data of long-range high-altitude targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target; collect data of long-range ground targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target; perform the same filtering process on the four types of data of the high-altitude targets and the ground targets, and compare them to obtain a demarcation value as a threshold; the specific implementation method is as follows:

[0047] 1) Collect data from high-altitude targets such as overpasses and road signs at a distance of 120 meters. The data content includes the following four types of content: absolute value of the main board angle, main-to-side ratio of pitch angle measurement, absolute value of the sidelobe angle, and MAG value.

[0048] 2) Collect data from ground targets such as cars, trucks, buses, motorcycles, electric vehicles, bicycles, people, etc. at a distance of 120 meters. The data content is the four types of content here.

[0049] 3) Filter the first three types of data using the same inter-frame filtering method to obtain filtering results of three contents. Obtain a trend line for the fourth type of MAG value data.

[0050] 4) Compare the four types of data of high-altitude targets and ground targets respectively to obtain the dividing value between high-altitude targets and ground targets. Above the dividing value is one type of target, and below the dividing value is another type of target. This dividing value is the threshold to be set.

[0051] When the absolute value of the angle where the main lobe is located is greater than the threshold, the main-to-side ratio of the pitch angle measurement is lower than the threshold, the absolute value of the angle where the side lobe is located is lower than the threshold, and the amplitude value growth of the target is lower than the expected curve, these four items can be specifically weighted, including: using equal weights, that is, giving the same weight to all; or through preliminary experiments, it is found that the absolute value of the angle where the side lobe is located is more effective, and more weight can be assigned. If the discrimination of the MAG value trend is not obvious enough, less weight can be assigned (for example, the absolute value of the angle where the side lobe is located is scored as 2 points, the MAG value trend is scored as 0.5 points, and the other two items are scored as 1 point each). Finally, the comprehensive score is calculated, and if a certain score is reached, it is considered to be a high-altitude target.

[0052] This method scores each frame, then filters the scores, and finally uses the filtered scores to discriminate. Specifically, ground targets have relatively small elevation angles, resulting in a smaller main lobe angle. Even with the influence of ground mirroring, the absolute value of the main lobe angle is relatively small. In contrast, high-altitude targets have relatively large main lobe angles. Due to the ground mirroring, the angle may be negative, but the absolute value is still large. Therefore, the absolute value of the main lobe angle can be used to distinguish high-altitude targets from ground targets.

[0053] For ground targets, the target is at a small elevation angle, and the target's mirror image is also at a small angle. For ordinary radars with a small number of channels and a small elevation aperture, the target and the target's mirror image cannot be distinguished, so they are equivalent to one target. For high-altitude targets, the target is at a relatively large elevation angle, and the target's mirror image is at a larger negative elevation angle. Therefore, the target or the mirror image will form a higher sidelobe, resulting in a smaller main-to-side ratio. The ground target and the ground target's mirror image will be equivalent to a single target, so the main-to-side ratio will be larger. Therefore, the main-to-side ratio information can be used to distinguish high-altitude targets from ground targets.

[0054] For ground targets, when the target is at a small pitch angle, the sidelobes will inevitably be at angles with larger absolute values. For high-altitude targets, when the target is at a large pitch angle, the sidelobes will be at angles with relatively smaller absolute values. Therefore, the absolute values ​​of the sidelobes can be used to distinguish high-altitude targets from ground targets.

[0055] For ground targets, the MAG value increases as the distance approaches. For high-altitude targets, the MAG value should increase as the distance approaches. However, for a high-altitude target at a fixed altitude, the pitch angle increases. The radar antenna gain decreases significantly at high pitch angles, so the MAG value does not increase as rapidly as for ground targets. Therefore, the MAG value trend can be used to help distinguish high-altitude targets from ground targets.

[0056] Target velocity can be used to filter out a large number of moving targets, strengthening the stability of high-altitude target recognition. The specific method is to compensate the target's velocity for the speed loss caused by the azimuth angle by v / cosθ, where θ is the target's measured azimuth angle and v is the target's speed relative to the radar. This value is then added to the vehicle's speed. If the result exceeds a certain speed range, the target is considered moving, eliminating the possibility of a high-altitude target.

[0057] The ego vehicle's speed is 20.8, and the motion threshold is 0.3. For example, if the target's speed is -20 and its azimuth is 15 degrees, then the compensated speed is -20 / cos15° = -20.7. The sum of the compensated speed and the ego vehicle's speed is -20.7 + 20.8 = 0.1, which is less than the threshold of 0.3. This indicates that the target is stationary, possibly a high-altitude target.

[0058] For example, if the target speed is -15 and the azimuth is 15 degrees, then the compensated speed is -15 / cos15° = -15.53. The sum of the compensated speed and the vehicle speed is -15.53 + 20.8 = 5.27, which is greater than the threshold of 0.3. This indicates that the target is a moving object and cannot be a high-altitude target.

[0059] like Figure 3-Figure 5 The following are examples of angle measurement curves for a ground target and a high-altitude target, respectively. In the angle measurement curves, the angle at which the peak with the highest amplitude is the main lobe. The peak with the second highest amplitude is the side lobe. The ratio of the main lobe peak amplitude to the side lobe peak amplitude is the main-to-side lobe ratio.

[0060] Ground targets have a relatively small pitch angle, so the main lobe angle is relatively small. Even with the influence of the ground image, the absolute value of the main lobe angle is relatively small. In contrast, high-altitude targets have a relatively large main lobe angle. Because of the ground image, the angle may be negative, but the absolute value is relatively large. Therefore, the absolute value of the main lobe angle can be used to distinguish high-altitude targets from ground targets.

[0061] For ground targets, the target is at a small elevation angle, and its mirror image is also at a small angle. For ordinary radars with a limited number of channels and a small elevation aperture, the target and its mirror image cannot be distinguished, and therefore they are considered as a single target. For high-altitude targets, however, the target is at a relatively large elevation angle, and its mirror image is at a relatively negative elevation angle. Therefore, the target or its mirror image forms a high sidelobe, resulting in a low main-to-side ratio. A ground target and its mirror image are considered as a single target, resulting in a higher main-to-side ratio.

[0062] For ground targets, if the target is at a smaller pitch angle, the side lobes will inevitably be at angles with larger absolute values. For high-altitude targets, if the target is at a larger pitch angle, the side lobes will be at angles with relatively smaller absolute values.

[0063] like Figure 6 As shown in the figure, for ground targets, the MAG value increases as the distance approaches. For high-altitude targets, the MAG value should increase as the distance approaches. However, as the distance approaches, for a high-altitude target at a fixed altitude, the pitch angle increases, and the radar antenna gain decreases significantly in the direction of large pitch angles. Therefore, the MAG value does not increase as rapidly as that of ground targets.

[0064] For an aerial target, it is primarily a stationary target. Therefore, when the ego vehicle moves forward, after compensating for the speed loss caused by the azimuth angle, its speed relative to the ego vehicle is close to negative. Therefore, the sum of its speed and the ego vehicle's speed is close to 0. If the difference exceeds a certain threshold, it is considered a moving target, and the possibility of an aerial target can be ruled out.

[0065] This method abandons the traditional method of directly using the pitch angle to calculate the height because it is found that there are relatively obvious differences between high-altitude targets and ground targets in four dimensions: the absolute value of the angle of the main lobe of the pitch measurement angle, the main-to-side ratio of the pitch measurement angle, the absolute value of the angle of the side lobe, and the amplitude value of the target. This method can distinguish high-altitude targets and ground targets relatively stably.

[0066] Example 2

[0067] In this embodiment, a common front radar long-range high-altitude target recognition system is proposed, such as Figure 2 Shown, including:

[0068] A processor for executing the method steps of a conventional front radar long-range high-altitude target recognition method;

[0069] A memory, used for storing an expected growth curve of a threshold value and a target amplitude value;

[0070] The data acquisition module is used to obtain the absolute value of the main lobe angle of the multi-frame pitch angle measurement, obtain the main lobe to side ratio of the multi-frame pitch angle measurement, and obtain the amplitude value of the multi-frame target;

[0071] A filtering module is used to perform inter-frame filtering on the absolute value of the angle of the main lobe of the pitch angle measurement, the main-to-side ratio of the pitch angle measurement, and the amplitude value of the target;

[0072] A threshold setting module is used to set the absolute value threshold of the main lobe angle of the pitch angle measurement, the main lobe to side ratio threshold of the pitch angle measurement, and the target amplitude value growth expected curve;

[0073] The judgment module is used to judge that the target is a high-altitude target when the angle of the main lobe of the pitch angle measurement is greater than the absolute value threshold, the main-to-side ratio of the pitch angle measurement is greater than the absolute value threshold, and the amplitude value growth of the target is less than the expected curve.

[0074] The display module is used to display the judgment results and the amplitude value distance curve of the target.

[0075] The speed compensation module is used to compensate the target speed for the speed loss caused by the azimuth angle v / cosθ, where θ is the measured azimuth angle, and add the compensated speed to the vehicle speed. If the result exceeds the set threshold, the high-altitude target is excluded.

[0076] The formula for compensating for the speed loss caused by the azimuth angle is: v_compensated=v / cosθ, where v is the speed of the target relative to the radar, and θ is the target azimuth angle.

[0077] In addition, when executed, the above modules are also used to implement other steps of the above-mentioned common front radar long-range high-altitude target recognition method, which will not be described one by one here.

[0078] In summary, the present invention significantly improves the robustness and accuracy of long-distance high-altitude target recognition by optimizing array design and multi-dimensional feature fusion, combined with a dynamic speed compensation mechanism. Specifically, increasing the number of pitch array elements effectively separates the main lobe and side lobe signals, and using multi-frame data filtering to extract side lobe angle features to suppress ground mirror interference; by fusing four types of differentiated features, a multi-dimensional criterion is established to distinguish target types; a speed compensation algorithm is introduced to dynamically determine the target motion state in combination with the vehicle's speed, effectively eliminating interference from moving ground targets. Ultimately, stable recognition of high-altitude targets within a distance of 120-200 meters is achieved, with recognition accuracy improved by more than 30%, and strong hardware adaptability, breaking through the angle measurement accuracy bottleneck and altitude calculation failure problems caused by the limitation of the number of channels in traditional solutions.

[0079] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for identifying long-range and high-altitude targets using a common front radar, characterized in that: The following steps are involved: The number of elevation array elements is set to be greater than 2 after MIMO. When the target is beyond the distance R, obtain the absolute value of the angle of the multi-frame pitch angle measurement side lobe; Performing inter-frame filtering on the absolute value of the angle at which the pitch angle measurement side lobe is located; Set the absolute value threshold of the angle where the pitch angle measurement side lobe is located; When the absolute value of the angle where the side lobe is located is smaller than the threshold, the target is determined to be a high-altitude target.

2. A method for identifying long-range high-altitude targets using a conventional front radar according to claim 1, characterized in that ,When the target is beyond the distance R, it also includes: Obtain the absolute value of the main lobe angle of multi-frame pitch angle measurement, obtain the main lobe ratio of multi-frame pitch angle measurement, and obtain the amplitude value of multi-frame targets; performing inter-frame filtering on the absolute value of the angle of the main lobe of the pitch angle measurement, the main-to-side ratio of the pitch angle measurement, and the amplitude value of the target; Set the absolute value threshold of the main lobe angle of the pitch angle measurement, the main lobe to side ratio threshold of the pitch angle measurement, and the target amplitude value growth expected curve; When the angle of the main lobe of the pitch angle measurement is greater than the absolute value threshold, the main-to-side ratio of the pitch angle measurement is greater than the absolute value threshold, and the amplitude value growth of the target is less than the expected curve, the target is determined to be a high-altitude target.

3. A common front radar long-range high-altitude target recognition method according to claim 1 or 2, characterized in that: The inter-frame filtering comprises: The absolute value of the angle where the main lobe is located, the main-to-side ratio of the pitch angle measurement, the absolute value of the angle where the side lobe is located, and the amplitude value of the target are respectively subjected to inter-frame filtering using Kalman filtering or α-β low-pass filtering.

4. A common front radar long-range high-altitude target recognition method according to claim 1 or 2, characterized in that: Determining the threshold value includes: Collect data of long-range high-altitude targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target; Collect data of long-range ground targets, including the absolute value of the main lobe angle, the main-to-side ratio of the pitch angle, the absolute value of the side lobe angle, and the amplitude value of the target; After the same filtering process is performed on the four types of data of the high-altitude targets and the ground targets, a dividing value is obtained by comparison and used as a threshold.

5. A common front radar long-range high-altitude target recognition system for implementing the method according to any one of claims 1 to 4, characterized in that: include: A processor, configured to execute the method according to any one of claims 1 to 3; A memory, used for storing an expected growth curve of a threshold value and a target amplitude value; The data acquisition module is used to obtain the absolute value of the main lobe angle of the multi-frame pitch angle measurement, obtain the main lobe to side ratio of the multi-frame pitch angle measurement, and obtain the amplitude value of the multi-frame target; A filtering module is used to perform inter-frame filtering on the absolute value of the angle of the main lobe of the pitch angle measurement, the main-to-side ratio of the pitch angle measurement, and the amplitude value of the target; A threshold setting module is used to set the absolute value threshold of the main lobe angle of the pitch angle measurement, the main lobe to side ratio threshold of the pitch angle measurement, and the target amplitude value growth expected curve; The judgment module is used to judge that the target is a high-altitude target when the angle of the main lobe of the pitch angle measurement is greater than the absolute value threshold, the main-to-side ratio of the pitch angle measurement is greater than the absolute value threshold, and the amplitude value growth of the target is less than the expected curve.

6. The common front radar long-range high-altitude target recognition system according to claim 5 is characterized in that: Also includes: The speed compensation module is used to compensate the target speed for the speed loss caused by the azimuth angle v / cosθ, where θ is the measured azimuth angle, and add the compensated speed to the vehicle speed. If the result exceeds the set threshold, the high-altitude target is excluded.

7. The common front radar long-range high-altitude target recognition system according to claim 6 is characterized in that: The formula for compensating for the speed loss caused by the azimuth angle is: v_compensated=v / cosθ, where v is the speed of the target relative to the radar, and θ is the target azimuth angle.

8. The common front radar long-range high-altitude target recognition system according to claim 7 is characterized in that: Also includes: The display module is used to display the judgment results and the amplitude value distance curve of the target.

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