A method, device and equipment for suppressing clutter in single pulse forward-looking imaging of polarization radar

Abstract

The present application relates to a method, device and equipment for suppressing clutter in a single pulse forward-looking imaging of a polarization radar. The method comprises: generating multiple sets of weights as multiple polarization states synthesized in a digital domain according to the expression form of the Jones vector; calculating the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence; calculating the entropy of the polarization-angle sequence of each range-Doppler unit as the polarization angle entropy; constructing a mask filter for range-Doppler data according to the polarization angle entropy; inputting the range-Doppler-sum-difference channel echo data into the mask filter, performing single pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter acts, accumulating each angle measurement result and the sum channel energy to the corresponding range-azimuth unit, and obtaining a distance-angle diagram for clutter suppression. The present method can suppress sea clutter by utilizing the information provided by the polarization dimension.

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 clutter in a polarization radar single-pulse forward-looking imaging. Background Art

[0002] Sea clutter can interfere with target echoes and reduce imaging resolution and clarity. Suppressing sea clutter can enhance target detection capabilities and make targets easier to identify in complex marine environments. It can improve the stability of imaging quality and is not affected by excessive changes in sea conditions. At the same time, it expands the application range of radar imaging and can achieve accurate imaging in high sea clutter areas, providing a reliable basis for maritime monitoring and rescue, greatly improving the effectiveness of radar in the marine environment, and is of great significance to ensuring maritime safety and conducting marine-related activities.

[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 property 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. Under different transmit and receive polarization states, the amplitude and phase of the scatterer are different, and the single-pulse angle measurement results are also different. Because the target unit has a single component, the angle measurement results under different polarization states are relatively stable; because the clutter unit has component aliasing, the angle measurement results under different polarization states fluctuate significantly. How to make full use of the information provided by the polarization dimension to achieve sea clutter suppression is an unresolved problem. Summary of the invention

[0004] Based on this, it is necessary to provide a polarization radar single-pulse forward-looking imaging clutter suppression method, device and equipment that can use the information provided by the polarization dimension to suppress sea clutter in order to solve the above-mentioned technical problems.

[0005] A polarization radar single pulse forward-looking imaging clutter suppression method, the method comprising:

[0006] Obtain range-Doppler-sum-difference channel echo data in the polarimetric radar sea detection scenario;

[0007] Generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence;

[0008] Calculate the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; construct a mask filter of range-Doppler data according to the polarization angle entropy;

[0009] The range-Doppler-sum-difference channel echo data are input into the mask filter, and single pulse angle measurement processing is performed on the range-Doppler-sum-difference channel echo data after the mask filter is applied. Each angle measurement result and the sum channel energy are accumulated into the corresponding range-azimuth unit to obtain the range-angle diagram of clutter suppression.

[0010] In one embodiment, the process of obtaining range-Doppler-sum-difference channel echo data in a polarization radar sea detection scenario includes:

[0011] Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to detect and obtain the scattered echo of the sea surface target. After preprocessing, the size of Echo complex data ,in, is the number of distance units; is the number of Doppler units; are the sum channel and the difference channel; is the number of polarization channels, in the dual-polarization system , in the fully polarized system ; Preprocessing includes matched filtering and coherent accumulation.

[0012] In one embodiment, multiple sets of weights are generated according to the expression of Jones vector as multiple equivalent polarization states synthesized in the digital domain, including:

[0013] According to the Jones vector expression:

[0014] ;

[0015] in, is the polarization ellipse geometry descriptor, , ;

[0016] The expression of Jones vector directly acts on dual-polarization data; for full-polarization data, the weight vector acting on it is expressed as ,in represents the Klaunec product operator.

[0017] In one embodiment, calculating the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence includes:

[0018] For a given range-Doppler unit , the sum data vector formed by each polarization channel is , the difference data vector is ;

[0019] Calculate the sum data vector and the difference data vector in the The angle measurement results under the action of the polarization state are:

[0020] ;

[0021] in, To take the imaginary part operator, Indicates The Jones vector corresponding to the polarization state;

[0022] According to the angle measurement under various polarization states, the polarization-angle sequence is constructed as follows:

[0023] ;

[0024] in, represents the total number of polarization states.

[0025] In one embodiment, calculating the entropy of each range-Doppler unit polarization-angle sequence as polarization angle entropy includes:

[0026] Range-Doppler unit The corresponding polarization angle entropy is:

[0027] ;

[0028] in, For the Angle measurement under the action of polarization state The probability of appearing in the entire sequence, represents the total number of polarization states.

[0029] In one embodiment, constructing a mask filter of range-Doppler data based on polarization angle entropy includes:

[0030] The mask filter for range-Doppler data constructed based on polarization angle entropy is:

[0031] ;

[0032] in, is the matrix composed of the polarization angle entropy of the range-Doppler unit, is the number of distance units; is the number of Doppler cells, It means that the mask filter is of size A real matrix of .

[0033] In one embodiment, single pulse angle measurement processing is performed on the range-Doppler-sum-difference channel echo data after the mask filter is applied, and each angle measurement result and the sum channel energy are accumulated into a corresponding range-azimuth unit to obtain a range-angle diagram for clutter suppression, including:

[0034] The range-Doppler unit under any polarization channel The angle measurement result after the data is filtered by the mask is:

[0035] ;

[0036] in, , , is the first Line The elements of the column, is the number before filtering and in the data matrix Line The elements of the column, is the number of mask filters in the matrix Line Elements of a column.

[0037] According to the angle measurement results and channel energy The corresponding range-azimuth units are accumulated to obtain the range-angle diagram of clutter suppression.

[0038] A polarization radar single pulse forward-looking imaging clutter suppression device, the device comprising:

[0039] The polarization-angle sequence construction module is used to obtain the range-Doppler-sum-difference channel echo data in the polarization radar sea detection scenario; generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of the Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence;

[0040] A mask filter design module is used to calculate the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; and construct a mask filter for range-Doppler data according to the polarization angle entropy;

[0041] The clutter suppression module is used to input the range-Doppler-sum-difference channel echo data into the mask filter, perform single-pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter acts on it, accumulate each angle measurement result and the sum channel energy into the corresponding range-azimuth unit, and obtain the range-angle diagram of clutter suppression.

[0042] 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:

[0043] Obtain range-Doppler-sum-difference channel echo data in the polarimetric radar sea detection scenario;

[0044] Generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence;

[0045] Calculate the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; construct a mask filter of range-Doppler data according to the polarization angle entropy;

[0046] The range-Doppler-sum-difference channel echo data are input into the mask filter, and single pulse angle measurement processing is performed on the range-Doppler-sum-difference channel echo data after the mask filter is applied. Each angle measurement result and the sum channel energy are accumulated into the corresponding range-azimuth unit to obtain the range-angle diagram of clutter suppression.

[0047] The above-mentioned polarization radar single pulse forward imaging clutter suppression method, device and equipment, the present application can effectively distinguish between targets and sea clutter by generating multiple polarization states and calculating the single pulse angle measurement results under different polarizations, and improve the detection capability of targets in complex marine environments. And calculate the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence, calculate the entropy of the polarization-angle sequence of each range-Doppler unit as the polarization angle entropy, use polarization information to construct a polarization-angle sequence and calculate the entropy value, which can accurately identify the clutter area and suppress the clutter, and improve the clarity and resolution of the distance-angle diagram. Based on the polarization angle entropy, a mask filter is constructed to effectively screen the clutter area and reduce the influence of clutter. The single pulse angle measurement processing is performed on the filtered data, and the energy of the sum and difference channels is accumulated to enhance the prominence of the target signal and reduce the interference of clutter. A clearer distance-angle diagram can be obtained, thereby effectively suppressing sea clutter. This application also enhances the adaptability to different sea conditions through information in the polarization dimension, ensuring high-quality imaging results even in high sea clutter areas. This application can achieve precise imaging in complex marine environments, expanding the application potential of radar technology in the fields of maritime monitoring and reconnaissance. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic flow chart of a method for suppressing clutter in a polarization radar single pulse forward-looking imaging in one embodiment;

[0049] Figure 2A simplified diagram of a polarization radar receiving data scenario in one embodiment;

[0050] Figure 3 A polarization-angle sequence comparison diagram of a target unit and a clutter unit in one embodiment;

[0051] Figure 4 A schematic diagram of polarization angle entropy calculation results in another embodiment;

[0052] Figure 5 is a mask filter calculation result of range-Doppler data in one embodiment;

[0053] Figure 6 is a difference channel range-Doppler diagram before and after clutter suppression in one embodiment; wherein, Figure 6 (a) is the difference channel range-Doppler diagram before clutter suppression. Figure 6 (b) is the difference channel range-Doppler diagram after clutter suppression;

[0054] Figure 7 : is a channel range-Doppler diagram before and after clutter suppression in one embodiment; wherein, Figure 7 (a) is the channel range-Doppler diagram before clutter suppression. Figure 7 (b) is the channel range-Doppler diagram after clutter suppression;

[0055] Figure 8 is a distance-angle diagram before and after clutter suppression in one embodiment; wherein, Figure 8 (a) is the distance-angle diagram before clutter suppression. Figure 8 (b) is the distance-angle diagram after clutter suppression;

[0056] Fig. 9 It is a structural block diagram of a polarization radar single pulse forward-looking imaging clutter suppression device in one embodiment;

[0057] Fig.10 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0058] 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.

[0059] In one embodiment, Figure 1 As shown, a polarization radar single pulse forward-looking imaging clutter suppression method is provided, comprising the following steps:

[0060] Step 102, obtaining the range-Doppler-sum-difference channel echo data in the sea detection scenario of the polarization radar; generating multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression of the Jones vector; calculating the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence.

[0061] like Figure 2 The figure shows a simplified diagram of the polarization radar receiving data scenario. The polarization radar uses a set of dual-polarization antennas with orthogonal polarization states for detection, obtains the scattered echo of the sea surface target, and then generates multiple polarization states by using the expression of Jones vectors, which can obtain the reflection characteristics of the target and clutter under different polarizations. Different polarization states make the signal performance of clutter and target significantly different. Polarization information provides a more dimensional reference for distinguishing targets and clutter. Then, the single pulse angle measurement results of each range-Doppler unit in different polarization states are calculated to form a polarization-angle sequence. Since the angle measurement results of the target in different polarization states are relatively stable, while the angle measurement results of the clutter fluctuate greatly, this difference can provide a basis for subsequent clutter suppression.

[0062] Step 104: Calculate the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; construct a mask filter for range-Doppler data according to the polarization angle entropy.

[0063] By calculating the entropy of the polarization angle sequence, the difference between the target and the clutter can be quantified. Areas with lower entropy values ​​usually correspond to stable signals of the target, while areas with higher entropy values ​​may be clutter areas, which helps to determine the clutter that needs to be suppressed. Constructing a mask filter for range-Doppler data based on the polarization angle entropy can effectively retain the target signal and suppress clutter in data processing. The mask filter will help to screen out clutter areas and effectively suppress them.

[0064] Step 106, input the range-Doppler-sum-difference channel echo data into the mask filter, perform single pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter is applied, accumulate each angle measurement result and the sum channel energy into the corresponding range-azimuth unit, and obtain a range-angle diagram for clutter suppression.

[0065] The range-Doppler-sum-difference channel echo data is input into the mask filter, and the range-Doppler-sum-difference channel echo data after the mask filter is applied is subjected to single pulse angle measurement processing. By performing single pulse angle measurement processing on the filtered data and accumulating the sum-difference channel energy, the prominence of the target signal can be enhanced while reducing the interference of clutter. Through this process, a clearer range-angle diagram can be obtained, thereby achieving effective suppression of sea clutter.

[0066] In the above-mentioned polarization radar single pulse forward imaging clutter suppression method, the present application can effectively distinguish between targets and sea clutter and improve the detection capability of targets in complex marine environments by generating multiple polarization states and calculating the single pulse angle measurement results under different polarizations. And calculate the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence, calculate the entropy of each range-Doppler unit polarization-angle sequence as polarization angle entropy, use polarization information to construct a polarization-angle sequence and calculate the entropy value, which can accurately identify the clutter area and suppress the clutter, and improve the clarity and resolution of the distance-angle diagram. Based on the polarization angle entropy, a mask filter is constructed to effectively screen the clutter area and reduce the influence of clutter. The single pulse angle measurement processing is performed on the filtered data, and the energy of the sum and difference channels is accumulated to enhance the prominence of the target signal and reduce the interference of clutter. A clearer distance-angle diagram can be obtained, thereby achieving effective suppression of sea clutter. This application also enhances the adaptability to different sea conditions through information in the polarization dimension, ensuring high-quality imaging results even in high sea clutter areas. This application can achieve precise imaging in complex marine environments, expanding the application potential of radar technology in the fields of maritime monitoring and reconnaissance.

[0067] In one embodiment, the process of obtaining range-Doppler-sum-difference channel echo data in a polarization radar sea detection scenario includes:

[0068] Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to detect and obtain the scattered echo of the sea surface target. After preprocessing, the size of Echo complex data ,in, is the number of distance units; is the number of Doppler units; are the sum channel and the difference channel; is the number of polarization channels, in the dual-polarization system , in the fully polarized system ; Preprocessing includes matched filtering and coherent accumulation.

[0069] In one embodiment, multiple sets of weights are generated according to the expression of Jones vector as multiple equivalent polarization states synthesized in the digital domain, including:

[0070] According to the Jones vector expression:

[0071] ;

[0072] in, is the polarization ellipse geometry descriptor, , ;

[0073] The expression of Jones vector directly acts on dual-polarization data; for full-polarization data, the weight vector acting on it is expressed as ,in represents the Klaunec product operator.

[0074] In one embodiment, calculating the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence includes:

[0075] For a given range-Doppler unit , the sum data vector formed by each polarization channel is , the difference data vector is ;

[0076] Calculate the sum data vector and the difference data vector in the The angle measurement results under the action of the polarization state are:

[0077] ;

[0078] in, To take the imaginary part operator, Indicates The Jones vector corresponding to the polarization state;

[0079] According to the angle measurement under various polarization states, the polarization-angle sequence is constructed as follows:

[0080] ;

[0081] in, represents the total number of polarization states.

[0082] In one embodiment, calculating the entropy of each range-Doppler unit polarization-angle sequence as polarization angle entropy includes:

[0083] Range-Doppler unit The corresponding polarization angle entropy is:

[0084] ;

[0085] in, For the Angle measurement under the action of polarization state The probability of appearing in the entire sequence, represents the total number of polarization states.

[0086] In one embodiment, constructing a mask filter of range-Doppler data based on polarization angle entropy includes:

[0087] The mask filter for range-Doppler data constructed based on polarization angle entropy is:

[0088] ;

[0089] in, is the matrix composed of the polarization angle entropy of the range-Doppler unit, is the number of distance units; is the number of Doppler cells, It means that the mask filter is of size A real matrix of .

[0090] In one embodiment, single pulse angle measurement processing is performed on the range-Doppler-sum-difference channel echo data after the mask filter is applied, and each angle measurement result and the sum channel energy are accumulated into a corresponding range-azimuth unit to obtain a range-angle diagram for clutter suppression, including:

[0091] The range-Doppler unit under any polarization channel The angle measurement result after the data is filtered by the mask is:

[0092] ;

[0093] in, , , is the first Line The elements of the column, is the number before filtering and in the data matrix Line The elements of the column, is the number of mask filters in the matrix Line Elements of a column;

[0094] According to the angle measurement results and channel energy The corresponding range-azimuth units are accumulated to obtain the range-angle diagram of clutter suppression.

[0095] In a specific embodiment, Figure 3 As shown, the polarization-angle sequences of the target unit and the clutter unit are displayed. It can be seen that the polarization-angle sequence of the target unit is relatively stable, while the polarization-angle sequence of the clutter unit fluctuates significantly. Figure 4 The polarization angle entropy calculated from the polarization-angle sequence of each range-Doppler unit is displayed. It can be seen that the polarization angle entropy of the target unit is small, while the polarization angle entropy of the clutter unit is large. This difference can be used to achieve clutter suppression. Figure 5The range-Doppler data mask filter constructed by polarization angle entropy is shown. It can be seen that after the filter is applied, the energy of the target unit will be greatly retained, and the energy of the clutter unit will be greatly suppressed. Figure 6 The difference channel range-Doppler diagram before and after clutter suppression is shown, where Figure 6 (a) is the difference channel range-Doppler diagram before clutter suppression. Figure 6 (b) is the difference channel range-Doppler diagram after clutter suppression. It can be seen that the energy of the clutter unit is significantly suppressed, which is beneficial to the improvement of single-pulse imaging quality. Figure 7 The channel range-Doppler diagram before and after clutter suppression is shown, where Figure 7 (a) is the channel range-Doppler diagram before clutter suppression. Figure 7 (b) is the channel range-Doppler diagram after clutter suppression. It can be seen that the energy of the clutter unit is significantly suppressed, which is beneficial to the improvement of single-pulse imaging quality. Figure 8 The single pulse imaging range-angle diagram before and after clutter suppression is shown, where Figure 8 (a) is the distance-angle diagram before clutter suppression. Figure 8 (b) is the distance-angle diagram after clutter suppression. It can be seen that the clutter near the ship formation is significantly suppressed and the imaging quality is improved.

[0096] In summary, the present application can effectively suppress sea clutter, improve the target-clutter ratio, and facilitate the detection and recognition of single-pulse imaging.

[0097] 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.

[0098] In one embodiment, Fig. 9 As shown, a polarization radar single pulse forward-looking imaging clutter suppression device is provided, comprising: a polarization-angle sequence construction module 902, a mask filter design module 904 and a clutter suppression module 906, wherein:

[0099] The polarization-angle sequence construction module 902 is used to obtain the range-Doppler-sum-difference channel echo data in the polarization radar sea detection scenario; generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of the Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence;

[0100] The mask filter design module 904 is used to calculate the entropy of the polarization-angle sequence of each range-Doppler unit as the polarization angle entropy; and construct a mask filter for the range-Doppler data according to the polarization angle entropy;

[0101] The clutter suppression module 906 is used to input the range-Doppler-sum-difference channel echo data into the mask filter, perform single pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter is applied, accumulate each angle measurement result and the sum channel energy into the corresponding range-azimuth unit, and obtain the range-angle diagram of clutter suppression.

[0102] For the specific definition of a polarization radar single pulse forward-looking imaging clutter suppression device, please refer to the definition of a polarization radar single pulse forward-looking imaging clutter suppression method above, which will not be repeated here. Each module in the above-mentioned polarization radar single pulse forward-looking imaging clutter suppression device 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 of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0103] 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.10 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 method for suppressing clutter in a polarization radar single-pulse forward-looking imaging 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 key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0104] Those skilled in the art will understand that Fig.10 The 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.

[0105] 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.

[0106] 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.

[0107] 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 method for clutter suppression of polarization radar single pulse forward imaging, characterized in that: The method comprises: Obtain range-Doppler-sum-difference channel echo data in the polarimetric radar sea detection scenario; Generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit under multiple polarization states to form a polarization-angle sequence; Calculating the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; constructing a mask filter of range-Doppler data according to the polarization angle entropy; The range-Doppler-sum-difference channel echo data are input into the mask filter, single pulse angle measurement processing is performed on the range-Doppler-sum-difference channel echo data after the mask filter acts, and each angle measurement result and the sum channel energy are accumulated into a corresponding range-azimuth unit to obtain a range-angle diagram for clutter suppression.

2. The method according to claim 1, characterized in that: The process of obtaining the range-Doppler-sum-difference channel echo data in the polarimetric radar sea detection scenario includes: Polarimetric radar uses a set of dual-polarized antennas with orthogonal polarization states to detect and obtain the scattered echo of the sea surface target. After preprocessing, the size of Echo complex data ,in, is the number of distance units; is the number of Doppler units; are the sum channel and the difference channel; is the number of polarization channels, in the dual-polarization system , in the fully polarized system ; The preprocessing includes matched filtering and coherent accumulation.

3. The method according to claim 1, characterized in that According to the expression of Jones vector, multiple sets of weights are generated as multiple equivalent polarization states synthesized in digital domain, including: According to the Jones vector expression: ； in, is the polarization ellipse geometry descriptor, , ; The expression of Jones vector directly acts on dual-polarization data; for full-polarization data, the weight vector acting on it is expressed as ,in represents the Klaunec product operator.

4. The method according to any one of claims 1 to 3, characterized in that: Calculate the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence, including: For a given range-Doppler unit , the sum data vector formed by each polarization channel is , the difference data vector is ; The sum data vector and the difference data vector are used to calculate the The angle measurement results under the action of the polarization state are: ； in, To take the imaginary part operator, Indicates The Jones vector corresponding to the polarization state; According to the angle measurement under various polarization states, the polarization-angle sequence is constructed as follows: ； in, represents the total number of polarization states.

5. The method according to claim 1, characterized in that: The entropy of each range-Doppler unit polarization-angle sequence is calculated as the polarization angle entropy, including: Range-Doppler unit The corresponding polarization angle entropy is: ； in, For the Angle measurement under the action of polarization state The probability of appearing in the entire sequence, represents the total number of polarization states.

6. The method according to claim 1, characterized in that Constructing a mask filter of range-Doppler data according to the polarization angle entropy, comprising: The mask filter for range-Doppler data constructed according to the polarization angle entropy is: ； in, is the matrix composed of the polarization angle entropy of the range-Doppler unit, is the number of distance units; is the number of Doppler cells, It means that the mask filter is of size A real matrix of .

7. The method according to claim 1, characterized in that Perform single pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter is applied, accumulate each angle measurement result and the sum channel energy into the corresponding range-azimuth unit, and obtain the range-angle diagram of clutter suppression, including: The range-Doppler unit under any polarization channel The angle measurement result after the data is filtered by the mask is: ； in, , , is the first Line The elements of the column, is the number before filtering and in the data matrix Line The elements of the column, is the number of mask filters in the matrix Line Elements of a column; According to the angle measurement results and channel energy The corresponding range-azimuth units are accumulated to obtain the range-angle diagram of clutter suppression.

8. A polarization radar single pulse forward imaging clutter suppression device, characterized in that: The device comprises: The polarization-angle sequence construction module is used to obtain the range-Doppler-sum-difference channel echo data in the polarization radar sea detection scenario; generate multiple sets of weights as multiple polarization states synthesized in the digital domain according to the expression form of the Jones vector; calculate the single pulse angle measurement results of each range-Doppler unit in multiple polarization states to form a polarization-angle sequence; A mask filter design module is used to calculate the entropy of the polarization-angle sequence of each range-Doppler unit as polarization angle entropy; and construct a mask filter for range-Doppler data according to the polarization angle entropy; The clutter suppression module is used to input the range-Doppler-sum-difference channel echo data into the mask filter, perform single pulse angle measurement processing on the range-Doppler-sum-difference channel echo data after the mask filter acts on it, accumulate each angle measurement result and the sum channel energy into a corresponding range-azimuth unit, and obtain a range-angle diagram for clutter suppression.

9. 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 7 are implemented.

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