Sea clutter suppression method, device and equipment based on polarization coherent filtering

Abstract

The present application relates to a method, device and equipment for suppressing sea clutter based on polarization coherent filtering. The method comprises: obtaining range-pulse echo data in a polarization radar sea detection scenario; calculating the polarization characteristic difference angle sequence between adjacent pulses of the same distance unit of the range-pulse echo data, and constructing a pulse amplitude weighted filter of the distance unit according to the obtained polarization characteristic difference angle sequence; calculating the pulse amplitude weighted filter of all distance units, performing pulse-dimensional Fourier transform on the range-pulse echo data, and obtaining a range-Doppler radar map after clutter suppression. The present method can utilize the polarization scattering information of the target to achieve effective suppression of sea clutter.

Description

Technical Field

[0001] The present application relates to the field of radar detection technology, and in particular to a method, device and equipment for suppressing sea clutter based on polarization coherent filtering. Background Art

[0002] As radar detection scenarios become increasingly complex and application areas continue to expand, the demand for radar sea detection is becoming increasingly urgent. However, tasks such as ocean surveillance and sea surface target detection are seriously affected by sea clutter. On the one hand, sea surface targets are constantly miniaturized and RCS is gradually reduced; on the other hand, the presence of sea peaks in high sea conditions further reduces the contrast between targets and clutter. Therefore, sea clutter has become an important factor affecting the performance of sea surface target detection and recognition, and sea clutter suppression is of great significance.

[0003] Traditional coherent integration and Doppler processing are technical approaches to improve the target-clutter ratio. Conventional sea clutter suppression methods mainly statistically model the clutter characteristics, use sea clutter samples to obtain model parameters, and then eliminate sea clutter according to the model. However, for non-Gaussian, non-stationary, and non-uniform sea clutter, its statistical characteristics are complex and the clutter suppression effect is poor in the case of mismatch. Polarization is an important attribute of electromagnetic waves. Polarimetric radar can obtain dual-polarization or full-polarization information of targets and clutter through a set of orthogonal dual-polarization antennas. Due to the effects of wind, gravity and tension on the sea surface, sea surface scatterers are always in motion. Changes in the shape of the sea surface cause changes in the polarization scattering characteristics of sea clutter; while the target structure and scattering characteristics are relatively stable, and there are significant differences in the polarization characteristics of sea clutter and targets. How to make full use of the polarization scattering information of the target to achieve effective suppression of sea clutter is an unresolved problem. Summary of the invention

[0004] Based on this, it is necessary to provide a sea clutter suppression method, device and equipment based on polarization coherent filtering that can utilize the polarization scattering information of the target to effectively suppress sea clutter in order to solve the above technical problems.

[0005] A sea clutter suppression method based on polarization coherent filtering, the method comprising:

[0006] Obtain range-pulse echo data in the polarization radar sea detection scenario;

[0007] Calculating the polarization characteristic difference angle sequence between adjacent pulses of the same range unit of the range-pulse echo data, and constructing a pulse amplitude weighted filter of the range unit according to the obtained polarization characteristic difference angle sequence;

[0008] Calculate the pulse amplitude weighted filter of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

[0009] In one embodiment, obtaining range-pulse echo data in a polarization radar sea detection scenario includes:

[0010] Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to transmit A pulse is used to detect the sea surface target and obtain the scattered echo of the sea surface target;

[0011] Preprocess the scattered echo to obtain the range-pulse data , for dimensional complex matrix data; where is the number of received pulses, is the number of range units, obtained by range gate setting and sampling, is the number of polarization channels. If single polarization transmission and dual polarization reception are used, then On the contrary, if dual-polarization time-sharing transmission and dual-polarization reception are adopted, then .

[0012] In one embodiment, calculating a sequence of polarization characteristic difference angles between adjacent pulses in a same range unit of range-pulse echo data includes:

[0013] For a distance unit Pulse echo data, starting from the first pulse, take the polarization channel data of the two adjacent pulses in sequence ;

[0014] The polarization channel data of the two pulses are constructed as two complex vectors , , the vector is a sequential arrangement of the elements of each polarization channel or a weighted combination of the elements of each polarization channel;

[0015] The angle between the two complex vectors is calculated, and the angle between the complex vectors is used as the polarization characteristic difference angle between the two pulses. The polarization characteristic difference angle sequence corresponding to the pulse sequence is calculated in sequence.

[0016] In one embodiment, calculating the angle between two complex vectors includes:

[0017] Calculate the angle between two complex vectors:

[0018] ;

[0019] in, is the dot product of two complex vectors, To take the absolute value, is the magnitude of the complex vector, The value range is ,and .

[0020] In one embodiment, constructing a pulse amplitude weighted filter of a range unit according to the obtained polarization characteristic difference angle sequence includes:

[0021] Constructing pulse amplitude weights Polarization characteristic difference angle The functional relationship between them is defined as

[0022] ;

[0023] in, satisfy and , , ,parameter The value can be determined according to the actual situation. ;

[0024] According to the polarization characteristics difference angle sequence The weight sequence of the pulse amplitude weighted filter can be obtained .

[0025] In one embodiment, performing pulse-dimensional Fourier transform on the range-pulse echo data to obtain a range-Doppler radar map after clutter suppression includes:

[0026] For any distance unit in the range-pulse echo data, the distance unit is Fourier transformed according to the pulse amplitude weighted filter corresponding to the distance unit to obtain the Doppler processed data; the Doppler processed data of all distance units are combined to obtain a The complex matrix , which is the range-Doppler radar diagram after clutter suppression.

[0027] In one embodiment, Fourier transform is performed on the distance unit according to the pulse amplitude weighted filter corresponding to the distance unit to obtain Doppler processed data, including:

[0028] The distance unit is Fourier transformed according to the pulse amplitude weighted filter corresponding to the distance unit, and the data after Doppler processing is obtained as follows:

[0029] ;

[0030] in, For the The distance unit corresponds to The echo data of a pulse, Indicates the number of received pulses. represents the pulse amplitude weight, that is, the pulse amplitude weighted filter, Indicates the frequency point number of the digital frequency after Fourier transform.

[0031] A sea clutter suppression device based on polarization coherent filtering, the device comprising:

[0032] A data acquisition module is used to acquire distance-pulse echo data in the scenario of polarization radar sea detection;

[0033] A polarization characteristic difference calculation module is used to calculate the polarization characteristic difference angle sequence between adjacent pulses of the same distance unit of the range-pulse echo data, and construct a pulse amplitude weighted filter of the distance unit according to the obtained polarization characteristic difference angle sequence;

[0034] The clutter suppression module is used to calculate the pulse amplitude weighted filter of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

[0035] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0036] Obtain range-pulse echo data in the polarization radar sea detection scenario;

[0037] Calculating the polarization characteristic difference angle sequence between adjacent pulses of the same range unit of the range-pulse echo data, and constructing a pulse amplitude weighted filter of the range unit according to the obtained polarization characteristic difference angle sequence;

[0038] Calculate the pulse amplitude weighted filter of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

[0039] The above-mentioned method, device and equipment for suppressing sea clutter based on polarization coherent filtering, the present application calculates the polarization characteristic differences between adjacent pulses by using the range-pulse echo data obtained by the polarization radar, and constructs a pulse amplitude weighted filter based on these differences. By filtering all distance units and applying the pulse-dimensional Fourier transform, sea clutter can be effectively suppressed and the contrast between the target and the clutter can be improved. The obtained range-Doppler radar map can significantly reduce clutter interference and effectively improve the contrast between the target and the clutter, especially in complex sea surface environments. This method improves the accuracy and reliability of target detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a diagram of an application scenario of a sea clutter suppression method based on polarization coherent filtering in an embodiment;

[0041] Figure 2 FIG. 1 is a schematic diagram of comparing dual-polarization echoes of different pulses of a target unit and a clutter unit in an embodiment; wherein: Figure 2 (a) Schematic diagram of dual-polarization echoes of different pulses representing the target unit, Figure 2 (b) Dual-polarization echoes of different pulses representing the clutter unit;

[0042] Figure 3 A schematic diagram of a target and clutter polarization characteristic difference filter in one embodiment;

[0043] Figure 4 It is a schematic diagram of the calculation result of the polarization characteristic difference angle between the target and the clutter unit in one embodiment;

[0044] Figure 5 A schematic diagram of the functional relationship between the pulse amplitude weight and the polarization characteristic difference angle in one embodiment;

[0045] Figure 6 A schematic diagram of a normalized amplitude diagram before and after clutter suppression in polarization coherent filtering in one embodiment;

[0046] Figure 7 Schematic diagram of the range-Doppler diagram before and after the clutter suppression of polarization coherent filtering in one embodiment; wherein, Figure 7 (a) is the range-Doppler diagram before clutter suppression. Figure 7 (b) is the range-Doppler diagram after clutter suppression;

[0047] Figure 8 is a structural block diagram of a sea clutter suppression device based on polarization coherent filtering in one embodiment;

[0048] Fig. 9 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0050] In one embodiment, Figure 1 As shown, a method for suppressing sea clutter based on polarization coherent filtering is provided, comprising the following steps:

[0051] Step 102: Acquire range-pulse echo data in a polarization radar sea detection scenario.

[0052] Polarimetric radar can obtain scattering information of sea surface targets and sea clutter through dual-polarized or fully polarized antennas. For each echo data, the radar system records the echo information of the target and clutter at different pulse times and different distances. By analyzing these echo signals, the difference in polarization characteristics between the target and clutter can be extracted, providing sufficient information for subsequent sea clutter suppression.

[0053] Step 104, calculating the polarization characteristic difference angle sequence between adjacent pulses of the same range unit of the range-pulse echo data, and constructing a pulse amplitude weighted filter of the range unit according to the obtained polarization characteristic difference angle sequence.

[0054] There are significant differences in the polarization scattering characteristics of clutter and targets on the sea surface. Usually, sea clutter shows more complex and irregular changes at different pulses and distances. This is because the sea surface is constantly changing with factors such as wind and gravity, resulting in a high degree of non-stationarity in its scattering characteristics. By calculating the polarization characteristic difference angle sequence between adjacent pulses of the same distance unit, the different performances of clutter and target in time and polarization dimensions can be captured. The scattering characteristics of the target are relatively stable, while sea clutter shows more complex and random polarization characteristic differences due to changes in the sea surface morphology. The difference angle sequence can reveal this change and serve as an effective feature to distinguish targets from clutter. After obtaining the polarization characteristic difference angle sequence, a pulse amplitude weighted filter is constructed to enhance the prominence of the target signal while suppressing the interference of clutter.

[0055] The amplitude response of the target signal can be enhanced by weighting the calculated polarization characteristic difference angle sequence. The weighted design of the filter strengthens the response of the target's scattering characteristics (usually more stable) in the echo signal, while the response of sea clutter (whose polarization characteristics are more dynamic and irregular) is suppressed, and the contrast between the target and the clutter is optimized by pulse dimension amplitude weighting.

[0056] Different weighted filters are constructed according to the different polarization characteristics of the target and clutter. For the distance unit with small changes in polarization characteristics, usually the target unit, an all-1 filter is used, and the amplitude does not change. For the filter with large changes in polarization characteristics, usually the clutter unit, the weight decays with the difference in polarization characteristics, and the amplitude is significantly reduced. This allows the influence of sea clutter to be effectively suppressed in practical applications.

[0057] Step 106, calculate the pulse amplitude weighted filters of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

[0058] In order to effectively suppress sea clutter in the entire detection area, it is necessary to calculate the pulse amplitude weighted filter for all distance units. The above design method is extended to the entire radar detection scenario, and corresponding filters are constructed for different distance units. The polarization characteristic difference angle sequence of each distance unit may be different, so the design of the filter will also be different. By calculating the filter of each distance unit, more accurate clutter suppression can be achieved based on the polarization characteristic differences of the local environment. Through Fourier transform, the signal between different pulse times can be analyzed in the frequency domain to extract the Doppler frequency and clutter characteristics.

[0059] Applying a pulse amplitude weighted filter in the frequency domain can effectively filter out clutter signals while retaining the target signal. Through weighted Fourier transform processing, the signal between different pulses can be analyzed in the frequency domain to extract the Doppler frequency and clutter characteristics, thereby enhancing the contrast of the target signal and reducing the interference of clutter. Finally, through pulse-dimensional Fourier transform and filtering processing, the range-Doppler radar map after clutter suppression can be obtained. This radar map shows the distribution of targets and clutter in terms of range and Doppler frequency. By analyzing these images, the location and characteristics of the target can be clearly identified, while significantly reducing the interference of clutter.

[0060] In the above-mentioned sea clutter suppression method based on polarization coherent filtering, the present application calculates the polarization characteristic differences between adjacent pulses by using the range-pulse echo data obtained by the polarization radar, and constructs a pulse amplitude weighted filter based on these differences. By filtering all distance units and applying the pulse-dimensional Fourier transform, sea clutter can be effectively suppressed and the contrast between the target and the clutter can be improved. The obtained range-Doppler radar map can significantly reduce clutter interference and effectively improve the contrast between the target and the clutter, especially in complex sea surface environments. This method improves the accuracy and reliability of target detection.

[0061] In one embodiment, obtaining range-pulse echo data in a polarization radar sea detection scenario includes:

[0062] Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to transmit A pulse is used to detect the sea surface target and obtain the scattered echo of the sea surface target;

[0063] Preprocess the scattered echo to obtain the range-pulse data , for dimensional complex matrix data; where is the number of received pulses, is the number of range units, obtained by range gate setting and sampling, is the number of polarization channels. If single polarization transmission and dual polarization reception are used, then On the contrary, if dual-polarization time-sharing transmission and dual-polarization reception are adopted, then .

[0064] In one embodiment, calculating a sequence of polarization characteristic difference angles between adjacent pulses in a same range unit of range-pulse echo data includes:

[0065] For a distance unit Pulse echo data, starting from the first pulse, take the polarization channel data of the two adjacent pulses in sequence ;

[0066] The polarization channel data of the two pulses are constructed as two complex vectors , , the vector is a sequential arrangement of the elements of each polarization channel or a weighted combination of the elements of each polarization channel;

[0067] The angle between the two complex vectors is calculated, and the angle between the complex vectors is used as the polarization characteristic difference angle between the two pulses. The polarization characteristic difference angle sequence corresponding to the pulse sequence is calculated in sequence.

[0068] In one embodiment, calculating the angle between two complex vectors includes:

[0069] Calculate the angle between two complex vectors:

[0070] ;

[0071] in, is the dot product of two complex vectors, To take the absolute value, is the magnitude of the complex vector, The value range is ,and .

[0072] In one embodiment, constructing a pulse amplitude weighted filter of a range unit according to the obtained polarization characteristic difference angle sequence includes:

[0073] Constructing pulse amplitude weights Polarization characteristic difference angle The functional relationship between them is defined as

[0074] ;

[0075] in, satisfy and ;

[0076] According to the polarization characteristics difference angle sequence The weight sequence of the pulse amplitude weighted filter can be obtained .

[0077] In a specific embodiment, a variety of functional relationships satisfy the above conditions. In this embodiment, a typical functional relationship is given, namely, a negative exponential function:

[0078] ;

[0079] parameter The value can be determined according to the actual situation. .

[0080] In one embodiment, performing pulse-dimensional Fourier transform on the range-pulse echo data to obtain a range-Doppler radar map after clutter suppression includes:

[0081] For any distance unit in the range-pulse echo data, the distance unit is Fourier transformed according to the pulse amplitude weighted filter corresponding to the distance unit to obtain the Doppler processed data; the Doppler processed data of all distance units are combined to obtain a The complex matrix , which is the range-Doppler radar diagram after clutter suppression.

[0082] In one embodiment, Fourier transform is performed on the distance unit according to the pulse amplitude weighted filter corresponding to the distance unit to obtain Doppler processed data, including:

[0083] The distance unit is Fourier transformed according to the pulse amplitude weighted filter corresponding to the distance unit, and the data after Doppler processing is obtained as follows:

[0084] ;

[0085] in, For the The distance unit corresponds to The echo data of a pulse, Indicates the number of received pulses. represents the pulse amplitude weight, that is, the pulse amplitude weighted filter, Indicates the frequency point number of the digital frequency after Fourier transform.

[0086] In a specific embodiment, a group of echo data of sea surface targets is simulated for subsequent analysis, the simulation center frequency is set to 10 GHz, the bandwidth is 150 MHz, the radar incident pitch angle is 20°, the sea clutter uses the pure clutter unit data of IPIX, and the target is a simulated point target. Figure 2 The dual-polarization echo data of different pulses of the target unit and the clutter unit are shown, where Figure 2 (a) Schematic diagram of dual-polarization echoes of different pulses representing the target unit, Figure 2 (b) shows the dual-polarization echoes of different pulses of the clutter unit. It can be seen that the polarization scattering characteristics of the target are relatively consistent between different pulses, while the polarization scattering characteristics of the clutter between different pulses are quite different. Figure 3 The schematic diagram of the polarization characteristic difference filter for different target and clutter distance units is shown. The slow time dimension in the figure represents different pulse echoes, and ellipses with different orientations represent different polarization states. For the distance unit where the clutter is located, the polarization characteristics of different pulses are quite different, and the amplitude weight of the constructed filter is less than 1, and the final amplitude is attenuated; for the distance unit where the target is located, the polarization characteristics of different pulses are basically the same, and the constructed filter is an all-1 filter. Figure 4 The polarization characteristic difference angles of the target unit and the clutter unit are displayed. It can be seen that the polarization characteristic difference angle of the target is basically 0, while the polarization characteristic difference angle of the clutter is larger. Figure 5 The relationship between the pulse amplitude weight and the polarization characteristic difference angle is shown. When the polarization characteristic difference is the same, the larger the value of k is, the smaller the pulse amplitude weight is. Therefore, it is necessary to select the appropriate weight according to the difference in the polarization characteristics of sea clutter in actual scenarios. Figure 6 The normalized amplitude results before and after clutter suppression are shown. It can be seen that the energy in the peak area where the target is located remains almost unchanged, while the energy in the clutter area is significantly reduced. Figure 7 The range-Doppler diagram before and after the polarization coherent filtering clutter suppression is shown, where Figure 7 (a) is the range-Doppler diagram before clutter suppression. Figure 7 (b) is the range-Doppler diagram after clutter suppression. Before clutter suppression, the contrast between the target and the background is not significant, but after clutter suppression, the contrast between the target and the clutter is obvious. In summary, the present application can effectively suppress sea clutter, improve the target-clutter ratio, and facilitate subsequent target detection.

[0087] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0088] In one embodiment, Figure 8 As shown, a sea clutter suppression device based on polarization coherent filtering is provided, comprising: a data acquisition module 802, a polarization characteristic difference calculation module 804 and a clutter suppression module 806, wherein:

[0089] The data acquisition module 802 is used to acquire the range-pulse echo data in the polarization radar sea detection scenario;

[0090] The polarization characteristic difference calculation module 804 is used to calculate the polarization characteristic difference angle sequence between adjacent pulses of the same range unit of the range-pulse echo data, and construct a pulse amplitude weighted filter of the range unit according to the obtained polarization characteristic difference angle sequence;

[0091] The clutter suppression module 806 is used to calculate the pulse amplitude weighted filter of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

[0092] For the specific definition of the sea clutter suppression device based on polarization coherent filtering, please refer to the definition of the sea clutter suppression method based on polarization coherent filtering above, which will not be repeated here. Each module in the above-mentioned sea clutter suppression device based on polarization coherent filtering can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0093] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Fig. 9 As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a sea clutter suppression method based on polarization coherent filtering is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0094] Those skilled in the art will understand that Fig. 9The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0095] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0096] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A sea clutter suppression method based on polarization coherent filtering, characterized in that: The method comprises: Obtain range-pulse echo data in the polarimetric radar sea detection scenario; Calculating the polarization characteristic difference angle sequence between adjacent pulses of the same range unit of the range-pulse echo data, including: For a distance unit Pulse echo data, starting from the first pulse, take the polarization channel data of the two adjacent pulses in sequence ; The polarization channel data of the two pulses are constructed as two complex vectors , the vector is a sequential arrangement of the elements of each polarization channel or a weighted combination of the elements of each polarization channel; Calculate the angle between the two complex vectors, use the complex vector angle as the polarization characteristic difference angle between the two pulses, and calculate the polarization characteristic difference angle sequence corresponding to the pulse sequence in sequence; A pulse amplitude weighted filter of a range unit is constructed according to the obtained polarization characteristic difference angle sequence; The pulse amplitude weighted filter of all range units is calculated, and the pulse-dimensional Fourier transform of the range-pulse echo data is performed to obtain the range-Doppler radar map after clutter suppression.

2. The method according to claim 1, characterized in that Obtain range-pulse echo data in the polarization radar sea detection scenario, including: Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to transmit A pulse is used to detect the sea surface target and obtain the scattered echo of the sea surface target; Preprocess the scattered echo to obtain range-pulse data , for dimensional complex matrix data; where is the number of received pulses, is the number of range units, obtained by range gate setting and sampling, is the number of polarization channels. If single polarization transmission and dual polarization reception are used, then On the contrary, if dual-polarization time-sharing transmission and dual-polarization reception are adopted, then .

3. The method according to claim 2, characterized in that Calculate the angle between two complex vectors, including: Calculate the angle between two complex vectors: in, is the dot product of two complex vectors, To take the absolute value, is the magnitude of the complex vector, The value range is ,and .

4. The method according to claim 1, characterized in that: A pulse amplitude weighted filter of a range unit is constructed according to the obtained polarization characteristic difference angle sequence, including: Constructing pulse amplitude weights Polarization characteristic difference angle The functional relationship between them is defined as in, satisfy and , , ; According to the polarization characteristics difference angle sequence The weight sequence of the pulse amplitude weighted filter can be obtained .

5. The method according to claim 1, characterized in that Perform pulse-dimensional Fourier transform on the range-pulse echo data to obtain the range-Doppler radar map after clutter suppression, including: For any distance unit in the range-pulse echo data, Fourier transform is performed on the distance unit according to the pulse amplitude weighted filter corresponding to the distance unit to obtain Doppler processed data; the Doppler processed data of all distance units are combined to obtain a The complex matrix , which is the range-Doppler radar diagram after clutter suppression.

6. The method according to claim 1, characterized in that Performing Fourier transform on the distance unit according to the pulse amplitude weighted filter corresponding to the distance unit to obtain Doppler processed data, including: The distance unit is subjected to Fourier transform according to the pulse amplitude weighted filter corresponding to the distance unit, and the data after Doppler processing is obtained as follows: in, For the The distance unit corresponds to The echo data of a pulse, Indicates the number of received pulses. represents the pulse amplitude weight, that is, the pulse amplitude weighted filter, Indicates the frequency point number of the digital frequency after Fourier transform.

7. A sea clutter suppression device based on polarization coherent filtering, characterized in that: The device comprises: A data acquisition module is used to obtain the range-pulse echo data in the polarization radar sea detection scenario; The polarization characteristic difference calculation module is used to calculate the polarization characteristic difference angle sequence between adjacent pulses in the same distance unit of the range-pulse echo data, including: For a distance unit Pulse echo data, starting from the first pulse, take the polarization channel data of the two adjacent pulses in sequence ; The polarization channel data of the two pulses are constructed as two complex vectors , the vector is a sequential arrangement of the elements of each polarization channel or a weighted combination of the elements of each polarization channel; Calculate the angle between the two complex vectors, use the complex vector angle as the polarization characteristic difference angle between the two pulses, and calculate the polarization characteristic difference angle sequence corresponding to the pulse sequence in sequence; A pulse amplitude weighted filter of a range unit is constructed according to the obtained polarization characteristic difference angle sequence; The clutter suppression module is used to calculate the pulse amplitude weighted filter of all range units, perform pulse dimension Fourier transform on the range-pulse echo data, and obtain the range-Doppler radar map after clutter suppression.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

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