A method for radar moving target indication (MTI) clutter suppression

Abstract

The application discloses a radar moving working clutter suppression method, S1 calculates the real-time vehicle speed compensation value of the working beam of the radar installation platform when moving, and realizes moving working resource scheduling. S2 compensates the echo signal of the radar according to the real-time vehicle speed compensation value, then detects the original point track of the radar detection target by means of phase comparison accumulation of the compensated echo signal, selects a fixed reference point in the geodetic coordinate system, and constructs a moving amplitude clutter map based on the original point track and the fixed reference point, wherein the moving amplitude clutter map has target point tracks. S3 establishes a false track judgment model based on time series Doppler velocity matching filtering by means of the historical motion track of the radar installation platform and the target point track, so that the judgment, marking and elimination of the fixed clutter point track and the false track are realized.

Description

Technical Field

[0001] This invention belongs to the field of radar signal processing, and particularly relates to a method for suppressing clutter during radar operation. Background Technology

[0002] During radar detection and tracking operations, the radar is inevitably affected by ground clutter, sea clutter, and meteorological clutter, depending on the geographical environment. To effectively suppress clutter interference, radar signal processing systems typically employ various clutter suppression techniques, including moving target indication (MTI), moving target detection (MTD), constant false alarm rate (CFAR) detection, and clutter maps. The main principle of using clutter maps for clutter suppression is to leverage the different time accumulation characteristics of clutter and target echoes. This involves statistically analyzing the spatial gridded clutter intensity distribution in the detection airspace, and continuously estimating the clutter background and refreshing the detection threshold through multiple smoothing echo scans, thereby reducing the detection of fixed clutter points.

[0003] In 1986, Nitzberg proposed the classic Nitzberg clutter map detection technique. This method stores the background estimate for each azimuth-range cell and iteratively updates the background clutter intensity during scanning. This process is unaffected by the spatial instability of ground clutter and sea clutter. In 1987, Levanon further developed other methods for calculating the false alarm probability of clutter map false alarms. Over the following three decades, scholars both domestically and internationally have successively optimized clutter map methods, with representative examples including cell average (CA) clutter maps, order statistic (OS) clutter maps, order data variable (ODV) clutter maps, and maximum reference cell (MRC) clutter maps. With the development of modern signal processing technology, clutter map processing can also be performed in the time-frequency domain by transforming the time-domain signal to the frequency domain.

[0004] Clutter mapping technology has a well-developed theoretical system, and although many types have emerged, each has its own advantages and disadvantages. The appropriate choice must be made based on the actual application scenario and specific conditions of the radar. Currently, most clutter mapping studies focus on stationary platforms, possessing theoretical universality. However, for applications requiring mobile operation, the effectiveness in suppressing clutter decreases significantly. When operating on the move, conventional clutter mapping methods do not consider the changes in the platform's reference center caused by platform movement, thus failing to effectively iterate over the clutter background for fixed ground features. They also do not consider that errors in signal processing, such as vehicle speed and attitude compensation, extend the echo energy of fixed ground features into low-speed channels, leading to the detection of clutter points. The increase in these residual clutter points increases the computational load of data processing, interferes with the initiation of normal tracks, increases the complexity of track-related processing, and affects radar detection performance. Summary of the Invention

[0005] The technical objective of this invention is to provide a method for suppressing clutter during radar operation, in order to solve problems such as excessive clutter and false tracks during search and tracking.

[0006] To solve the above problems, the technical solution of the present invention is as follows:

[0007] A method for suppressing operational clutter during radar travel includes the following steps:

[0008] S1: Calculate the real-time vehicle speed compensation value of the working beam when the radar installation platform is moving, and realize the scheduling of working resources while moving;

[0009] S2: The radar echo signal is compensated according to the real-time vehicle speed compensation value. The original trace of the radar target is obtained by coherently accumulating the compensated echo signal. A fixed reference point is selected in the geodetic coordinate system. A traveling amplitude clutter map is constructed based on the original trace and the fixed reference point. The target trace exists in the traveling amplitude clutter map.

[0010] S3: Utilize the historical motion trajectories and target points of the radar installation platform to establish a false track judgment model based on time-series Doppler velocity matched filtering, thereby realizing the judgment, marking, and elimination of fixed clutter points and false tracks.

[0011] Specifically, in step S1, the real-time vehicle speed compensation value is calculated by extracting the real-time northward, eastward, and upward speeds of the vehicle body from the radar mounting platform based on the acquired positioning and orientation data. ;

[0012] Based on the direction of the geodetic coordinate system during radar travel, the working beam is scheduled. ;

[0013] Calculate and obtain the real-time vehicle speed compensation value. The calculation formula is:

[0014] .

[0015] Furthermore, in step S1, the on-the-go work resource scheduling specifically involves acquiring the real-time location of the radar installation platform. The GPS location information, its latitude, longitude and altitude data are The real-time location of the radar installation platform The data is aggregated, and other scheduling information is obtained.

[0016] Specifically, in step S2, the construction of the inter-travel amplitude clutter map based on the original spot and the fixed reference point is as follows:

[0017] The real-time target position of the original point trace is converted from the geodetic coordinate system to the geocentric rectangular coordinate system.

[0018] The real-time coordinates of the target relative to the radar mounting platform in the geodetic coordinate system at that moment are: The real-time location of the radar installation platform is The target's current position in the geocentric rectangular coordinate system is...

[0019]

[0020] A fixed reference point is selected, and the coordinates of the fixed reference point in the geocentric rectangular coordinate system are: Then, in the geocentric rectangular coordinate system, calculate the position of the target relative to the fixed reference point in the geodetic coordinate system. At that time

[0021]

[0022] Obtain the relative position Based on relative position Construct a traveling amplitude clutter map.

[0023] More preferably, in step S2, the detection of the target point is specifically as follows:

[0024] If the amplitude radar measurement value of the currently detected point is The estimated values ​​of the previous clutter background intensity in the area of ​​the current point's azimuth, elevation, and distance are: Current clutter background intensity estimate The calculation formula is

[0025]

[0026] in, This is the updated weighting factor for the clutter background intensity;

[0027] For the amplitude radar measurement value of the currently detected point. The threshold was compared with the previous estimate of clutter background intensity.

[0028] like If the condition is met, then it is determined that a target point exists; otherwise, it is determined that a target point does not exist. Threshold factor for clutter plot detection.

[0029] Specifically, step S3 includes the following steps:

[0030] S301: Calculate the time-varying sequence of Doppler velocity of a fixed clutter spot;

[0031] S302: Based on the movement trajectory of the radar mounting platform, calculate the time sequence of the Doppler velocity of the fixed clutter spot relative to the radar mounting platform in real time.

[0032] S303: Establish a false track judgment model based on time series velocity matching to realize the judgment of fixed clutter points and false tracks, and realize the judgment, marking and elimination of fixed clutter points and false tracks based on the judgment results of fixed clutter points.

[0033] Specifically, in step S301, the accurate Doppler velocity of the clutter spot is fixed. The calculation formula is

[0034]

[0035] in, For GPS time, This is the real-time vehicle speed compensation value for the fixed clutter spot. The Doppler velocity value measured after vehicle speed compensation for the fixed clutter spot;

[0036] Assuming the observation time is ,common There are fixed clutter spots, and the CPS time for detecting the fixed clutter spots is as follows: The time-varying sequence of the Doppler velocity of the radar corresponding to the fixed clutter spot is as follows:

[0037] .

[0038] Furthermore, in step S302, the observation time is set to... , A fixed clutter spot on the radar

[0039] In the coordinate system, the distance, azimuth, and elevation angles are respectively , The corresponding heading and speed of the radar installation platform are as follows: ;

[0040] The Doppler velocity of the fixed clutter point relative to the radar mounting platform for

[0041]

[0042] The time sequence of the Doppler velocity of the fixed clutter spot relative to the radar mounting platform is as follows:

[0043] .

[0044] Preferably, in step S303, if the accurate Doppler velocity of the clutter spot is fixed... With solid

[0045] Doppler velocity of the fixed clutter point relative to the radar mounting platform When the Doppler velocity variation patterns are completely consistent, it is determined to be a fixed clutter point; when the variation patterns are inconsistent, it is determined to be a normal target.

[0046] Furthermore, in step S303, the following can also be performed respectively: and The Doppler velocity sequence was segmented, and the selected time was... The sequence within a single observation segment is obtained and And by performing a fast Fourier transform, we can obtain:

[0047]

[0048] If the following formula is met, the marker is determined to be a fixed clutter marker; otherwise, it is a normal target marker. The determination formula is as follows:

[0049]

[0050] in, This represents the allowable error range for the frequency of Doppler velocity variation during travel.

[0051] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art:

[0052] This invention constructs a composite amplitude and velocity clutter map under moving scenarios based on prior information about the motion characteristics of the radar mounting platform, thereby improving the clutter suppression performance of the radar during transit. This method utilizes real-time information about the position, heading, and velocity of the moving platform to first construct an amplitude clutter map in a geodetic coordinate system based on position compensation. This solves the problem that conventional clutter map thresholds cannot iterate normally when the radar is in motion, and is applicable to transit operations.

[0053] Then, based on the velocity variation law of the relative motion trajectory of fixed clutter, and the clutter point traces of fixed ground objects based on time series Doppler velocity matched filtering, it can effectively identify and suppress fixed clutter and the false tracks it generates.

[0054] Therefore, the present invention can effectively improve the clutter suppression capability of radar when it is in motion, reduce the false alarm probability, and improve detection and tracking performance. Attached Figure Description

[0055] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0056] Figure 1 This is a block diagram illustrating the implementation of a radar clutter suppression method during operation according to the present invention.

[0057] Figure 2 This is a gridded diagram of the traveling amplitude clutter map of the present invention;

[0058] Figure 3 This is a schematic diagram illustrating the change in heading angle during travel according to the present invention;

[0059] Figure 4 This is a comparison chart of the Doppler velocity measurement during travel according to the present invention;

[0060] Figure 5 This is a comparison chart of the frequency of Doppler velocity changes during the movement of the present invention;

[0061] Figure 6 This is a schematic diagram showing the relationship between the radar's operating route and the location of fixed ground features according to the present invention;

[0062] Figure 7 This is a distribution map of measured flight paths generated by the radar on fixed ground features during its operation, according to the present invention.

[0063] Figure 8 This is a distribution diagram of the measured Doppler velocity values ​​relative to fixed ground objects during the operation of the radar of this invention. Detailed Implementation

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0065] To keep the drawings concise, only the parts relevant to the invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of components with the same structure or function is shown schematically, or only one is labeled. In this document, "one" can mean not only "only one" but also "more than one".

[0066] The present invention provides a method for suppressing radar clutter during transit, which will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims.

[0067] Example

[0068] See Figures 1 to 8 This embodiment provides a method for suppressing clutter during radar operation while the radar is in motion. This method is mainly implemented through two modules: a data processing module and a signal processing module. First, in the signal processing module, an amplitude clutter map based on a fixed reference point is constructed, taking into account the characteristics of the radar mounting platform's motion. Then, in the data processing module, a false track judgment model is built using the radar mounting platform's trajectory to further identify and eliminate clutter points and false tracks. This achieves adaptive clutter suppression based on a composite clutter map, suitable for radar operation while the radar is in motion.

[0069] The detailed steps are as follows: First, in step S1, the real-time vehicle speed compensation value of the working beam of the radar installation platform when it is moving is calculated, and the working resources are scheduled during the movement.

[0070] Based on the acquired positioning and orientation data, the real-time vehicle speeds in the north, east, and sky directions of the radar mounting platform are extracted, respectively. The direction of the geodetic coordinate system is determined by the working beam of the radar during its travel. This allows for the calculation and acquisition of real-time vehicle speed compensation values. The calculation formula is:

[0071] .

[0072] Furthermore, the real-time location of the radar installation platform is then obtained. The GPS location information, with latitude, longitude, and altitude data as follows: The real-time location of the radar installation platform The information is aggregated and other scheduling information is obtained and sent to the signal processing module.

[0073] Next, see Figure 2In this embodiment, step S2 compensates the radar echo signal according to the real-time vehicle speed compensation value, and then coherently accumulates the compensated echo signal to obtain the original point trace of the radar-detected target. A fixed reference point is selected in the geodetic coordinate system, and a traveling amplitude clutter map is constructed based on the original point trace and the fixed reference point. The traveling amplitude clutter map contains target point traces.

[0074] like Figure 2 As shown, assume the radar mounting platform and the initial position of the radar are... ,area For the platform to be in The spatial grid of the traveling clutter map is determined by distance, azimuth, and beam elevation at a given time, and the region is... Center relative to Point distance, azimuth, and elevation are respectively .

[0075] Typically, when the radar is stationary and operating, the reference center for target detection remains consistent, thus enabling area detection within the same coordinate system. The system establishes and iteratively updates clutter maps based on the clutter situation within the platform. However, when the platform moves, the change in the measurement reference center will cause changes in the radar's measurements of stationary ground features. Clutter spots at the same location will spread to other clutter cells, and directly using the original clutter map division and iteration method will not be able to achieve effective accumulation and updating of the clutter background.

[0076] Therefore, when At that moment, the radar followed the platform from its initial location. Run to location At that time, in the same geodetic coordinate system, the region In the present The range, azimuth, and elevation in the radar coordinate system centered at point will all change, denoted as The real-time coordinates of the target in the geodetic coordinate system are obtained by conversion. .

[0077] It is necessary to determine the position of the target in the geodetic coordinate system relative to a fixed reference point during the journey. In a unified geocentric rectangular coordinate system, the starting point... The coordinates in the geocentric rectangular coordinate system are The platform location is Utilizing real-time targets (areas) Coordinates in the geodetic coordinate system and platform location Based on the following formula

[0078]

[0079] The position of the target in the geocentric rectangular coordinate system is obtained as follows .

[0080] Then use the following formula

[0081]

[0082] The target is calculated to have a relatively fixed reference point (i.e., the starting point). The position in the geodetic coordinate system is Then use relative position Construct a traveling amplitude clutter map based on a geodetic coordinate system.

[0083] Preferably, in step S2, the detection of the target point is specifically as follows: Assume the amplitude radar measurement value of the currently detected point is... The estimated values ​​of the previous clutter background intensity in the area of ​​the current point's azimuth, elevation, and distance are: Current clutter background intensity estimate The calculation formula is

[0084]

[0085] in, This is the updated weighting factor for the clutter background intensity.

[0086] For the amplitude radar measurement value of the currently detected point. Compare this with the threshold calculated from the previous clutter background intensity estimate. If the condition is met, then it is determined that a target point exists; otherwise, it is determined that a target point does not exist. Threshold factor for clutter plot detection.

[0087] Then, in step S3, during the platform's movement, the radar moves in real time with the platform, resulting in relative motion with stationary objects and thus a Doppler velocity. When the signal processing module performs detection, it first compensates for this Doppler velocity. However, due to the rapid frequency of attitude changes during platform movement, including potential turning and sudden attitude shifts, errors occur in the speed compensation calculation, resulting in a small Doppler velocity remaining in the clutter traces after speed compensation. Therefore, during coherent accumulation detection in signal processing, the fixed target is still detected, and the Doppler velocity is non-zero.

[0088] Therefore, in step S301, the accurate Doppler velocity of the clutter spot is fixed. The calculation formula is

[0089]

[0090] in, For GPS time, This is the real-time vehicle speed compensation value for the fixed clutter spot. The Doppler velocity value is the value measured after vehicle speed compensation for the fixed clutter spot.

[0091] Assuming the observation time is ,common There are fixed clutter spots, and the CPS time for detecting the fixed clutter spots is as follows: The time-varying sequence of the Doppler velocity of the radar corresponding to the fixed clutter spot is as follows:

[0092] .

[0093] Furthermore, due to the platform's movement, the relative motion leads to more clutter from fixed objects.

[0094] The Doppler velocity changes in real time. For example, when the angle of the platform's vehicle is aligned with the direction of the ground feature, the Doppler velocity value is at its maximum; when the vehicle's direction is not aligned with the direction of the ground feature, the angle of deviation will cause the Doppler velocity to gradually decrease, and when the vehicle's direction is at 90° with the direction of the ground feature, the Doppler velocity value is 0.

[0095] Therefore, in step S302, the observation time is set to... , The range, azimuth, and elevation angles of the fixed clutter points in the radar coordinate system are as follows: , The corresponding heading and speed of the radar installation platform are as follows: Based on the platform's motion trajectory, the Doppler velocity of the fixed clutter point relative to the radar mounting platform is calculated. for

[0096]

[0097] The subsequent time-varying sequence of the Doppler velocity of the fixed clutter spot relative to the radar mounting platform during travel can be calculated as follows:

[0098] .

[0099] Preferably, in step S303, for the fixed clutter spot and the generated false navigation...

[0100] The Doppler velocity change of the track exhibits a sinusoidal correlation with the platform's trajectory. Simultaneously, step S301 allows for real-time calculation of the Doppler velocity and its variation pattern of the clutter track. For the same fixed ground target, while the radar is in motion, the formula... The calculated Doppler velocity variation law of the point track should conform to the formula. The calculations are completely consistent. Therefore, the variation patterns of the two Doppler velocities at the time of clutter spot and false track generation can be matched to determine and mark time-series fixed clutter. When the variation patterns of the two Doppler velocities are completely consistent, it can be determined as a fixed clutter spot; when the variation patterns are inconsistent, it can be determined as a normal target.

[0101] Preferably, according to the formula It can be seen that, in

[0102] When the platform is in motion, the Doppler velocity relative to fixed ground features and the change in the platform vehicle's heading angle exhibit a sinusoidal pattern. For more complex travel routes where the heading is constantly adjusted left and right, the angle difference between the point and the platform vehicle's heading is actually in a non-uniform process, meaning there is angular rotational acceleration, such as... Figure 3 As shown.

[0103] To address this complex situation, the observation process can be divided into multiple segments. Within each segment's time interval L, the process can be approximated as a linear change in heading with uniform turning, and the vehicle speed can be approximated as constant within each segment. Segmentation reduces the time required for iterative data analysis, facilitates rapid calculations, and improves judgment efficiency. For sinusoidal patterns, considering engineering feasibility, a Fast Fourier Transform can be used for analysis.

[0104] Specifically, respectively for and The Doppler velocity sequence was segmented, and the selected time was... The sequence within a single observation segment is obtained and And by performing a fast Fourier transform, we can obtain:

[0105]

[0106] For the Doppler velocity with a sinusoidal variation law and There is a peak point and The frequency value of the peak point reflects the platform's performance. The frequency of changes in heading angle during travel. Theoretically, the frequencies of clutter tracks and spurious tracks generated by fixed ground features are identical. When performing a Fast Fourier Transform, the number of tracks is taken into account. Usually less, for and The sequence is padded with zeros to ensure that the number of sequences is a power of 2 before performing the Fourier transform.

[0107] If the following formula is met, the marker is determined to be a fixed clutter marker; otherwise, it is a normal target marker. The determination formula is as follows:

[0108]

[0109] in, The allowable error range for the frequency of Doppler velocity variation during travel is usually set to a small value close to 0 to address measurement quantization errors caused by the limitation of radar velocity resolution and to avoid slight deviations in the frequency of the peak value.

[0110] Preferably, the implementation results of this embodiment are analyzed to verify its feasibility. The experimental verification process is divided into two parts: simulation experiment and actual test. In the simulation, the signal processing measurement value is compared with the theoretical value based on the heading by simulating the change in the heading of the vehicle's front end. In the actual test, the radar is installed on the radar mounting platform and moves counterclockwise along a circular runway with the vehicle to launch a target drone, verifying that it can stably track the real target drone while suppressing clutter during travel.

[0111] Figure 4 This simulation demonstrates a comparison of Doppler velocity measurements during movement. The simulation was set at a vehicle speed of 10 m / s, with fixed ground features. During movement, the vehicle's front initially turned left, then right. As the vehicle turned left, the Doppler velocity continuously increased due to the changing azimuth angle. When it began turning right, the Doppler velocity started to decrease. The different slopes of the peak Doppler velocity on either side of the figure indicate that the vehicle's turning speed differed when turning left and right. Figure 4 Simulation results show that when working in motion, the formulas based on steps S301 and S302 of this embodiment have estimation errors in the velocity values, but the variation law of Doppler velocity remains consistent.

[0112] Figure 5 The simulation results show a comparison of the frequency (or period) of Doppler velocity changes during operation. The simulation results indicate that after performing a Fast Fourier Transform (FFT) in step S303 of this embodiment, both the measured Doppler velocity values ​​relative to fixed ground features and the theoretical values ​​based on the running trajectory exhibit peaks. The frequency of these peaks indicates the frequency (or period) of the Doppler velocity changes. The two peaks in the figure are at the same frequency, which also indicates that the Doppler velocity change pattern is the same for fixed ground features in this embodiment. Therefore, an FFT processing model is used to construct a clutter discrimination model to determine whether the clutter is a fixed clutter point.

[0113] Figure 6 A schematic diagram showing the relationship between the radar's operating route and the location of ground features was displayed. During the test, the vehicle speed was kept relatively constant at 30 km / h, traveling along a circular track with a radius of approximately 200 meters, and at a distance of approximately 2.5 km from the radar.

[0114] Figure 7The document demonstrates measured values ​​of the flight paths generated by the radar when it is operating on fixed ground objects. Before adopting the method described in this embodiment, although the radar performed vehicle speed compensation during detection in the signal processing module, the fixed ground objects were diffused into the non-zero speed Doppler channel due to factors such as compensation accuracy, thus detecting the target and establishing false flight paths.

[0115] Figure 8 This demonstrates the measured Doppler velocity of the radar relative to a fixed ground object while it is in motion. Since the fixed ground objects are consistently positioned, the angular difference between the vehicle's front and the ground object's azimuth varies uniformly and periodically within the range of 0° to 360°. Therefore, the Doppler velocity of the moving radar relative to the ground object is calculated using the formula... The calculation results in a sine curve. Figure 8 The measured results show that the radar measurements of Doppler velocity exhibit a clear sinusoidal curve pattern, consistent with the theoretical sinusoidal curve pattern. After processing with Fast Fourier Transform, the frequency (or period) of the Doppler velocity variation can be extracted based on the peak value. In summary, the Doppler velocity matching-based determination method of this embodiment can identify and mark clutter spot tracks, reducing false tracks.

[0116] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A method for suppressing clutter during radar operation while it is in motion, characterized in that, Includes the following steps: S1: Calculate the real-time vehicle speed compensation value of the working beam when the radar installation platform is moving, and realize the scheduling of working resources while moving; S2: The radar echo signal is compensated according to the real-time vehicle speed compensation value, and the original trace of the radar target is obtained by coherent accumulation detection of the compensated echo signal. A fixed reference point in the geodetic coordinate system is selected, and a traveling amplitude clutter map is constructed based on the original trace and the fixed reference point. The traveling amplitude clutter map contains target traces. Specifically, in step S2, constructing the inter-travel amplitude clutter map based on the original point trace and the fixed reference point involves: The real-time target position of the original point trace is converted from the geodetic coordinate system to the geocentric rectangular coordinate system. The real-time coordinates of the target relative to the radar mounting platform in the geodetic coordinate system at that moment are: The real-time location of the radar installation platform is The target's current position in the geocentric rectangular coordinate system is... The fixed reference point is selected, and the coordinates of the fixed reference point in the geocentric rectangular coordinate system are: Then, in the geocentric rectangular coordinate system, calculate the position of the target relative to the fixed reference point in the geodetic coordinate system. At that time Obtain the relative position Then based on relative position Construct the in-travel amplitude clutter map; S3: Using the historical motion trajectory of the radar mounting platform and the target point, establish a false track judgment model based on time series Doppler velocity matching, thereby realizing the judgment, marking and elimination of fixed clutter points and false tracks; Step S3 specifically includes the following steps. S301: Calculate the time-varying sequence of Doppler velocity of a fixed clutter spot; S302: Based on the movement trajectory of the radar mounting platform, calculate the time sequence of the Doppler velocity of the fixed clutter spot relative to the radar mounting platform in real time. S303: Establish a false track judgment model based on time series velocity matching to realize the judgment of fixed clutter points and false tracks, and realize the judgment, marking and elimination of fixed clutter points and false tracks based on the fixed clutter point judgment results.

2. The radar clutter suppression method during transit according to claim 1, characterized in that, In step S1, the calculation of the real-time vehicle speed compensation value specifically involves extracting the real-time northward, eastward, and upward speeds of the vehicle body from the radar mounting platform based on the acquired positioning and orientation data. ; Based on the direction of the geodetic coordinate system during radar travel, the working beam is scheduled. ; The real-time vehicle speed compensation value is calculated and obtained. The calculation formula is: 。 3. The radar clutter suppression method during transit according to claim 1, characterized in that, In step S1, the on-the-go work resource scheduling specifically involves obtaining the real-time location of the radar installation platform. The GPS location information, its latitude, longitude and altitude data are The real-time location of the radar installation platform The data is aggregated, and other scheduling information is obtained.

4. The radar clutter suppression method during transit according to claim 1, characterized in that, In step S2, the detection of the target point is specifically as follows: If the amplitude radar measurement value of the currently detected point is The estimated values ​​of the previous clutter background intensity in the area of ​​the current point's azimuth, elevation, and distance are: Current clutter background intensity estimate The calculation formula is in, This is the updated weighting factor for the clutter background intensity; For the amplitude radar measurement value of the currently detected point. The threshold was compared with the previous estimate of clutter background intensity. like If the target point exists, then it is determined that the target point exists; otherwise, it is determined that the target point does not exist. Threshold factor for clutter plot detection.

5. The radar clutter suppression method during transit according to claim 1, characterized in that, In step S301, the accurate Doppler velocity of the clutter spot is fixed. The calculation formula is in, For GPS time, This is the real-time vehicle speed compensation value for the fixed clutter spot. The Doppler velocity value measured after vehicle speed compensation for the fixed clutter spot; Assuming the observation time is ,common There are fixed clutter spots, and the CPS time for detecting the fixed clutter spots is as follows: The time-varying sequence of the Doppler velocity of the radar corresponding to the fixed clutter spot is as follows: 。 6. The radar clutter suppression method during transit according to claim 5, characterized in that, In step S302, the observation time is set to... , A fixed clutter spot in the radar coordinate system The downward distance, azimuth, and elevation angles are respectively , The corresponding heading and speed of the radar installation platform are as follows: ; The Doppler velocity of the fixed clutter point relative to the radar mounting platform for The time sequence of the Doppler velocity of the fixed clutter spot relative to the radar mounting platform is as follows: 。 7. The radar travel clutter suppression method according to claim 6, characterized in that, In step S303, if the accurate Doppler velocity of the clutter spot is fixed... With fixed miscellaneous Doppler velocity of the dot relative to the radar mounting platform When the Doppler velocity variation patterns are completely consistent, it is determined to be a fixed clutter point; when the variation patterns are inconsistent, it is determined to be a normal target.

8. The radar clutter suppression method during transit according to claim 7, characterized in that, Furthermore, in step S303, the following are also performed respectively: and The Doppler velocity sequence was segmented, and the time interval was selected as... The sequence within a single observation segment is obtained and And by performing a fast Fourier transform, we can obtain: If the following formula is met, the marker is determined to be a fixed clutter marker; otherwise, it is a normal target marker. The determination formula is as follows: in, This represents the allowable error range for the frequency of Doppler velocity variation during travel.

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