A method for constructing interior scenes based on measured data characteristic models

Abstract

The present invention relates to a method for constructing an interior scene based on a measured data characteristic model, which belongs to the field of electromagnetic scene simulation technology and solves the technical problems of echo characteristic distortion and poor target polarization characteristic simulation fidelity in the existing technology for interior electromagnetic scene simulation. The method comprises: building a plurality of exterior test scenes and obtaining the measured radar target echo data in each exterior test scene; generating a target characteristic library and a background noise library based on the measured radar target echo data in each exterior test scene; selecting a target scattering characteristic model from the target characteristic library and selecting background noise data from the background noise library according to the scene setting requirements of the interior scene; generating a radar simulated target echo in the interior scene according to the scene setting requirements and the target scattering characteristic model of each simulated target, superimposing the background noise data to obtain the radar simulated echo signal in the interior scene, and completing the construction of the interior scene.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic scene simulation, and in particular to a method for constructing an interior field scene based on a measured data characteristic model. Background Art

[0002] Currently, with the increasing complexity of radar jamming countermeasure scenarios, comprehensive verification of radar jamming countermeasure performance has become increasingly difficult. Passive jammers primarily consist of various false targets. Verifying radar countermeasure performance through field tests across various scenarios is prohibitively expensive. Therefore, employing indoor simulated jamming countermeasure electromagnetic scenarios is the future direction of development. Indoor electromagnetic scenario simulation allows for interaction between radar and signal sources within a darkroom, simulating the echoes of targets and false targets detected by the radar, enabling testing of radar hardware and software. Currently, false targets are increasingly similar in appearance to targets, and radars employ full polarization and high-resolution range to enhance their perception capabilities. To effectively verify radar target and false target discrimination performance indoors, realistic simulation of the polarization and range profile characteristics of indoor electromagnetic scenarios is necessary.

[0003] Existing methods for simulating internal electromagnetic scenes mainly simulate point targets detected by radar through signal sources, or simulate echoes of scene targets with one-dimensional range profile characteristics by modulating the target electromagnetic model. However, for the simulation of false target countermeasures, these methods have the following shortcomings:

[0004] 1) It can only simulate single-pulse non-coherent radar echoes, but lacks the ability to simulate coherent radar echoes. The echo characteristics of the simulated scene after coherent accumulation are distorted.

[0005] 2) When simulating the full-polarization signal echo in the indoor field, there is a problem of poor simulation fidelity of the target polarization characteristics, which cannot meet the requirements of verifying the target and false target identification algorithm based on polarization information. Summary of the Invention

[0006] In view of the above analysis, an embodiment of the present invention aims to provide an indoor field scene construction method based on a measured data characteristic model, which can solve the technical problems in the prior art of echo characteristic distortion and poor simulation fidelity of target polarization characteristics in indoor field electromagnetic scene simulation.

[0007] The present invention discloses a method for constructing an interior scene based on a measured data characteristic model, comprising:

[0008] Build a variety of field test scenarios and obtain measured radar target echo data in each field test scenario;

[0009] Generate target characteristic library and background noise library based on the measured radar target echo data in various field test scenarios;

[0010] According to the scene setting requirements of the indoor scene, a target scattering characteristic model is selected from the target characteristic library, and background noise data is selected from the background noise library;

[0011] In the indoor scene, according to the scene setting requirements and the target scattering characteristic model of each simulated target, the radar simulated target echo is generated;

[0012] The background noise data selected from the background noise library is superimposed on the generated radar simulated target echo to obtain the radar simulated echo signal in the interior scene, thereby completing the construction of the interior scene.

[0013] On the basis of the above solution, the present invention also makes the following improvements:

[0014] Next, generate the target feature library by performing the following operations:

[0015] Process the measured radar target echo data under each field test scenario to obtain the corresponding range-Doppler data; select the target area on the obtained range-Doppler data and mark the target area's target type, location range, radar equipment parameters, and target parameters;

[0016] For each target area, all strong scattering points and their characteristic vectors in the target area are extracted to obtain a target scattering characteristic model of the target area;

[0017] The target type, radar equipment parameters, target parameters and target scattering characteristic model of each target area are summarized to form a target characteristic library.

[0018] Furthermore, the target scattering characteristic model of each target area is obtained by performing the following operations:

[0019] Extracting range-Doppler data of the target area according to the marked position range of the target area;

[0020] Obtain the scattering point with the maximum energy in the range-Doppler data of the target area;

[0021] Determine whether the energy of the scattering point is greater than or equal to the set multiple of the average energy of the background noise in the entire range-Doppler data of the target area,

[0022] If so, the scattering point is extracted as a strong scattering point, and the characteristic vector of the strong scattering point is obtained; then, the strong scattering point is eliminated from the range-Doppler data of the target area, the range-Doppler data of the target area is updated, and the process jumps to the step of finding the scattering point with the maximum energy;

[0023] Otherwise, the process of extracting the strong scattering points and their characteristic vectors in the target area ends;

[0024] All strong scattering points and their characteristic vectors in the target area are summarized to construct a target scattering characteristic model of the target area.

[0025] Furthermore, the characteristic vector of the strong scattering point includes:

[0026] Coordinates of strong scattering points: distance of the strong scattering point in the target area - distance and Doppler position in Doppler data;

[0027] Normalized scattering parameter set of strong scattering points: normalized scattering parameters of strong scattering points on the four polarization channels of HH, HV, VH, and VV.

[0028] Next, generate a background noise library by doing the following:

[0029] Based on the non-target areas in the measured radar target echo data under various sea conditions, the background noise data under the corresponding sea conditions are formed; the background noise data under all sea conditions are summarized to form a background noise library.

[0030] Furthermore, the scene setting requirements include:

[0031] The target type of the simulation target, which can be one or more;

[0032] Radar equipment parameters, including radar band and polarization state;

[0033] Scenario environment parameters, including sea conditions, radar equipment altitude, and radar-target distance.

[0034] Further, selecting a target scattering characteristic model from the target characteristic library includes:

[0035] Based on the scene environment parameters of the simulation target, obtaining the target parameters of the simulation target;

[0036] According to the target type, radar band and target parameters of each simulated target, the target scattering characteristic model matching each simulated target is retrieved from the target characteristic library;

[0037] Select background noise data from the background noise library, including:

[0038] According to the sea condition information in the scene setting requirements, background noise data matching the sea condition is selected from the background noise library.

[0039] Furthermore, the radar simulated target echo is generated by performing the following operations:

[0040] Generate radar transmission signals according to radar equipment parameters in the scenario setting requirements;

[0041] Based on the target scattering characteristic model of each simulated target and the radar transmission signal, a radar simulated target echo of the corresponding simulated target is obtained;

[0042] If the scene setting requirements only include one simulated target, the radar simulated target echo of the simulated target is used as the radar simulated target echo in the indoor field scene; otherwise, the radar simulated target echoes of all simulated targets are superimposed with electromagnetic waves to obtain the radar simulated target echo in the indoor field scene.

[0043] Further, the radar simulated target echo of the simulated target is obtained by performing the following operations:

[0044] Reconstructing the range-Doppler data of the simulated target in a full polarization state according to the retrieved target scattering characteristic model of the simulated target;

[0045] Performing decoherent accumulation processing on the reconstructed range-Doppler data of the simulated target in full polarization state to obtain one-dimensional range image data corresponding to the simulated target;

[0046] According to the radar-target distance in the scenario setting requirements, the one-dimensional range image data of the simulated target is superimposed on the corresponding position of the radar-target distance to form a range image target scattering point set of the simulated target;

[0047] The target characteristic of the range image target scattering point set of the simulated target is modulated by using the radar transmission signal to generate the radar simulated target echo of the simulated target.

[0048] Furthermore, the range-Doppler data of the simulated target in all polarization states are reconstructed by performing the following operations:

[0049] Using the coordinates of each strong scattering point in the target scattering characteristic model of the simulated target as the coordinate points in the reconstructed range-Doppler data;

[0050] The normalized scattering parameter set of each strong scattering point in the target scattering characteristic model of the simulated target is used as the value of the corresponding coordinate point in the reconstructed range-Doppler data;

[0051] The rest of the locations without strong scattering points have a value of 0;

[0052] Thus, the range-Doppler data of the simulated target in full polarization state is reconstructed.

[0053] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0054] The method for constructing an interior scene based on a measured data characteristic model provided by the present invention has the following advantages:

[0055] 1. By extracting the characteristics of measured data to build a target scattering characteristic model, the radar target echo range profile characteristics are more realistic. Compared with existing technologies, this technology can meet the requirements of high-resolution radar recognition performance test environment;

[0056] 2. Using full polarization data to simultaneously extract the polarization scattering of each scattering point, the polarization characteristics of the radar target echo constructed in the indoor field are more realistic;

[0057] 3. Separate background noise or clutter data from the measured data and superimpose it with the target echo during electromagnetic scene reconstruction to achieve a more realistic simulated electromagnetic background. Compared with the internal field method, this technology can simulate realistic echoes under strong clutter background.

[0058] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following description, and some advantages will become apparent from the description or be learned through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The accompanying drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like parts throughout the drawings.

[0060] Figure 1 A flow chart of the method for constructing an interior scene based on a characteristic model of measured data;

[0061] Figure 2 This is a flow chart of another method for constructing an interior scene based on a measured data characteristic model. DETAILED DESCRIPTION

[0062] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0063] A specific embodiment of the present invention discloses a method for constructing an interior scene based on a measured data characteristic model, the flow chart of which is as follows: Figure 1 and Figure 2 As shown, the method for constructing the interior scene includes:

[0064] Step S1: construct multiple field test scenarios and obtain measured radar target echo data in each field test scenario;

[0065] In this embodiment, each outdoor test scenario includes at least one target. Since this embodiment aims to construct indoor scenarios based on the actual outdoor test scenarios, the various outdoor test scenarios in this embodiment should cover all possible targets involved in indoor scenarios to be applicable to different indoor scenarios. Furthermore, after the outdoor test scenarios are constructed, radar echo data for each outdoor test scenario is collected through actual measurement as the corresponding measured radar target echo data.

[0066] Step S2: Generate a target characteristic library and a background noise library based on the measured radar target echo data in each field test scenario; specifically, it includes:

[0067] Step S21: Process the measured radar target echo data in each field test scenario respectively to obtain the corresponding range-Doppler data; select the target area on the obtained range-Doppler data, and mark the target type, position range, radar equipment parameters and target parameters of the target area.

[0068] Specifically, in this embodiment, the measured radar target echo data in the field test scenario is pulse compressed and coherently accumulated to obtain the range-Doppler data corresponding to the measured radar target echo data. After obtaining the range-Doppler data, the area whose energy is significantly greater than the background noise can be selected from the range-Doppler data as the target area. It should be noted that if there are more than one target in a field test scenario, in the process of determining the target area, it is also necessary to use the radar-target distance corresponding to each target recorded during the field test (for ship-type targets, the observation side angle is also included) and other information to distinguish the target area corresponding to each target.

[0069] After the target area is defined, the target type, location range, radar equipment parameters and target parameters of the target area can be marked; preferably,

[0070] Target types include: ship-type targets, angle-reflection targets and chaff targets; for example, ship-type targets are distinguished by ship type; for angle-reflection targets, they are distinguished by angle-reflection type; for chaff targets, they are distinguished by chaff model.

[0071] Position range, which indicates the coordinate information of the target area in the range-Doppler data;

[0072] Radar equipment parameters, including radar band and polarization state.

[0073] Target parameters include the grazing angle of incidence. Specifically, for ship-type targets, these parameters also include the observed broadside angle and radial velocity. In actual processing, the radar-target distance must be recorded to calculate the grazing angle. The grazing angle is the angle between the beam direction and the horizontal plane of the target position; the observed broadside angle is the angle between the radar's direct line of sight to the target and the ship's heading; and the radial velocity is the target's speed in the direction the radar is pointing.

[0074] Step S22: for each target area, extract all strong scattering points and their characteristic vectors in the target area to obtain a target scattering characteristic model of the target area;

[0075] Specifically, all strong scattering points in each target area are extracted by performing the following operations:

[0076] Step S221: extracting the range-Doppler data of the target area according to the marked position range of the target area;

[0077] Step S222: obtaining the scattering point with the maximum energy in the range-Doppler data of the target area;

[0078] Step S223: Determine whether the energy of the scattering point is greater than or equal to a set multiple of the average energy of the background noise in the entire range-Doppler data where the target area is located (i.e., the average energy of the non-target area in the entire range-Doppler data).

[0079] If so, the scattering point is extracted as a strong scattering point, and a characteristic vector of the strong scattering point is obtained. Then, the strong scattering point is removed from the range-Doppler data of the target area, the range-Doppler data of the target area is updated, and the process jumps to step S222, i.e., the scattering point with the maximum energy is searched again in the updated range-Doppler data of the target area.

[0080] Otherwise, the process of extracting the strong scattering points and their characteristic vectors in the target area ends.

[0081] In actual implementation, the set multiple is set based on the discrimination between the target and background noise and the accuracy requirement of the target feature library storage. For example, the set multiple is 4 times.

[0082] In this embodiment, the extracted characteristic vectors of the strong scattering points include:

[0083] Coordinates of strong scattering points: distance of the strong scattering point in the target area - distance and Doppler position in Doppler data;

[0084] Normalized scattering parameter set of strong scattering points: normalized scattering parameters of strong scattering points on the four polarization channels of HH, HV, VH, and VV.

[0085] In this embodiment, the normalized scattering parameters of the strong scattering points on the four polarization channels of HH, HV, VH, and VV are determined by the following method:

[0086] (1) Obtaining the range-Doppler data of an ideal point target; specifically, using the transmitted wave pattern in the field test scenario as the ideal point target echo, and obtaining the range-Doppler data of the ideal point target through pulse compression and coherent accumulation processing;

[0087] (2) Using the range-Doppler data of the ideal point target, the complex coefficient decomposition of the strong scattering point on the four polarization channels of HH, HV, VH, and VV is performed to obtain the scattering parameters of the strong scattering point on the corresponding polarization channel;

[0088] (3) Based on the RCS (Radar Cross Section) normalization method, the scattering parameters on each polarization channel are normalized to obtain the normalized scattering parameters of the strong scattering point on the corresponding polarization channel. In this way, the normalized scattering parameters of the strong scattering point on the four polarization channels (HH, HV, VH, and VV) are obtained.

[0089] In this process, the sensor parameters and scene parameters can be completely eliminated through the RCS normalization method.

[0090] By summarizing all the strong scattering points and their characteristic vectors in the target area, the target scattering characteristic model of the target area can be constructed. The representation of the target scattering characteristic model is shown in Table 1. Taking the target scattering characteristic model C1 corresponding to ship type 1 as an example, in C1, R i and D i They represent the distance and Doppler position of the i-th strong scattering point in the target scattering characteristic model, S i_hh ,S i_hv ,S i_vh ,S i_vv Represents the normalized scattering parameter of the i-th strong scattering point in the target scattering characteristic model on the four polarization channels HH, HV, VH, and VV. i = 1, 2, ..., N1, where N1 is the total number of strong scattering points in the target scattering characteristic model C1.

[0091] Step S23: Summarize the target type, radar equipment parameters, target parameters, and target scattering characteristic model of each target area to form a target characteristic library;

[0092] For example, in the target feature library, some examples are represented as shown in Table 1.

[0093] Table 1 Example of some contents of target characteristic library

[0094]

[0095] Step S24: Based on the non-target areas in the measured radar target echo data under various sea conditions, background noise data under corresponding sea conditions are formed; and the background noise data under all sea conditions are summarized to form a background noise library.

[0096] Step S3: According to the scene setting requirements of the indoor scene, a target scattering characteristic model is selected from the target characteristic library, and background noise data is selected from the background noise library.

[0097] In this embodiment, based on the customary representation method in the scene test, the scene setting requirements for the indoor scene are set; preferably, the scene setting requirements include:

[0098] (1) Target type of simulated target

[0099] The simulation target is one or more;

[0100] (2) Radar equipment parameters

[0101] Similar to the outdoor test scenario, the radar equipment parameters in the indoor test scenario also include radar band and polarization state. It should be noted that since the corresponding horizontal polarization direction and vertical polarization direction related data can be obtained based on the target scattering characteristic model under the full polarization state, and at the same time, the test conditions of the outdoor test scenario are effectively utilized, in the outdoor test scenario, the polarization state of the radar should be set to full polarization. In the indoor test scenario, the polarization state of the radar can be limited according to the scenario setting requirements, such as horizontal polarization, vertical polarization, or full polarization.

[0102] (3) Scene environment parameters

[0103] Scenario environment parameters include sea condition information, altitude of radar equipment, and radar-target distance;

[0104] In particular, the scene environment parameters of ship-type targets also include heading and speed;

[0105] The scene environment parameters of the chaff target also include the altitude of the chaff target.

[0106] Step S31: acquiring target parameters of the simulation target based on the scene environment parameters of the simulation target;

[0107] The target parameters are the same as those in the target characteristic library;

[0108] (1) Grazing angle

[0109] Based on the radar altitude and radar-target distance in the scene environment parameters of the simulated target, the corresponding incidence angle is determined; specifically, the incidence angle refers to the angle between the beam direction and the horizontal plane of the target position. The incidence angle can be calculated using the formula Calculate and obtain, where A target 、A radar 、D r,t Represents the target's altitude, radar's altitude, and radar-target distance, respectively. In actual applications, the default altitude for ship-type and angular radar-type targets is 0.

[0110] (2) Observe the side angle

[0111] The observed side angle is calculated by taking the port side as negative and the starboard side as positive, based on the direction of the radar pointing directly at the target and the heading of the ship.

[0112] (3) Radial velocity

[0113] The radial velocity is obtained by calculating the ship's heading and speed.

[0114] Step S32: According to the target type, radar band and target parameters of each simulated target, a target scattering characteristic model matching each simulated target is retrieved from the target characteristic library.

[0115] It should be noted that the matching in step S32 refers to:

[0116] A target data is searched in the target characteristic library for a target type and radar band consistent with the simulated target, and target parameters that meet the preset threshold deviation requirements, and the target scattering characteristic model in the target data is used as the target scattering characteristic model of the simulated target.

[0117] Preferably, the target parameters satisfy the preset threshold deviation requirement, which means that each parameter in the target parameters of the simulated target is compared with the corresponding parameter in the target characteristic library, and each parameter should satisfy the threshold deviation of the parameter.

[0118] Step S33: Based on the sea condition information in the scene setting requirements, background noise data matching the sea condition is selected from the background noise library.

[0119] Step S4: In the indoor scene, according to the scene setting requirements and the target scattering characteristic model of each simulated target, generate a radar simulated target echo;

[0120] Step S41: Generate a radar transmission signal according to the radar device parameters in the scene setting requirements;

[0121] Specifically, the band to which the radar transmit signal belongs is determined according to the radar band in the radar equipment parameters; the polarization wave of the radar transmit signal is determined according to the polarization state in the radar equipment parameters; illustratively, if the polarization state is horizontal polarization, the radar transmit signal is a horizontally polarized wave; if the polarization state is vertically polarized, the radar transmit signal is a vertically polarized wave; if the polarization state is full polarization, the radar transmit signal includes horizontally polarized waves and vertically polarized waves transmitted simultaneously.

[0122] Step S42: obtaining a radar simulated target echo of the corresponding simulated target based on the target scattering characteristic model of each simulated target and the radar transmission signal;

[0123] For each simulated target, obtain the radar simulated target echo of the simulated target by performing the following operations:

[0124] Step S421: Reconstruct the range-Doppler data of the simulated target in the full polarization state according to the retrieved target scattering characteristic model of the simulated target; specifically,

[0125] Using the coordinates of each strong scattering point in the target scattering characteristic model of the simulated target as the coordinate points in the reconstructed range-Doppler data;

[0126] The normalized scattering parameter set of each strong scattering point in the target scattering characteristic model of the simulated target is used as the value of the corresponding coordinate point in the reconstructed range-Doppler data;

[0127] The rest of the locations without strong scattering points are set to 0;

[0128] Thus, the range-Doppler data of the simulated target in full polarization state is reconstructed;

[0129] Step S422: performing decoherent accumulation processing on the reconstructed range-Doppler data of the simulated target in all polarization states to obtain one-dimensional range profile data corresponding to the simulated target;

[0130] Step S423: According to the radar-target distance in the scene setting requirement, the one-dimensional range image data of the simulated target is superimposed on the corresponding position of the radar-target distance to form a range image target scattering point set of the simulated target.

[0131] Step S424: using the radar transmission signal to modulate the target characteristic of the range image target scattering point set of the simulated target to generate a radar simulated target echo of the simulated target;

[0132] The formula for target characteristic echo modulation is expressed as:

[0133]

[0134]

[0135] Among them, S HH 、S HV 、S VH and S VV The range image target scattering point sets of the four polarization channels HH, HV, VH, and VV are respectively, H is the horizontally polarized wave emitted by the radar, st V is the vertically polarized wave emitted by the radar, rt H is the horizontal polarization simulated target echo obtained by modulation, rt V The vertical polarization simulated target echo is obtained by modulation.

[0136] Step S43: If the scene setting requirement includes only one simulated target, the radar simulated target echo of the simulated target is used as the radar simulated target echo in the indoor scene;

[0137] Otherwise, the radar simulated target echoes of all simulated targets are superimposed with electromagnetic waves to obtain the radar simulated target echoes in the indoor scene.

[0138] After completing the target characteristic echo modulation, the echo generation of the multi-target scenario can be completed based on the target characteristics after echo modulation by utilizing the superposition of electromagnetic waves. Specifically, in this embodiment, utilizing the superposition of electromagnetic waves, assuming that each target within the radar beam illumination range is at a certain distance and there is no electromagnetic mutual coupling, such as in the case of angle reversal, the multi-target scenario is generated by the superposition of single target echoes. By selecting multiple targets and setting their spatial positions, a single target is first simulated separately, and then time-series echo superposition is performed based on the target distance. The echoes of multiple targets in the beam at the same time in the multi-target scenario can be expressed as follows:

[0139]

[0140] Among them, Rt H , Rt V They represent the horizontal polarization simulated target echo and vertical polarization simulated target echo in the indoor scene, rt H_j ,rt V_j They respectively represent the horizontally polarized simulated target echo and the vertically polarized simulated target echo of the j-th simulated target in the scene setting requirements.

[0141] Step S5: Background noise data selected from the background noise library is superimposed on the generated radar simulated target echo to obtain the radar simulated echo signal in the interior scene, thereby completing the construction of the interior scene.

[0142] Furthermore, in the present invention, in order to realistically simulate the echo background noise, after generating the radar simulated target echo in the indoor scene, the background noise is superimposed on it, and the radar simulated echo signal in the indoor scene is obtained after superposition. The expression is as follows:

[0143] r H =Rt H +rn H

[0144] r V =Rt V +rn V

[0145] Among them, r H 、r V Respectively represent the horizontal polarization radar simulation echo signal and vertical polarization radar simulation echo signal in the indoor scene; H 、rn V Represent the background noise data in the horizontal polarization direction and the vertical polarization direction respectively.

[0146] The indoor scene can be either an indoor darkroom or a digital simulation. The difference is that in the indoor darkroom scenario, the actual radar equipment needs to receive the radar analog echo signal through the antenna; in the digital simulation mode, the radar equipment samples the digital circuit form of simulation implementation, without the need for an antenna, and directly transmits the radar analog echo signal to the radar's signal processing module, so that the radar signal processing module can perform subsequent processing operations based on the radar analog echo signal and the radar transmission signal.

[0147] In summary, this embodiment provides a method for constructing an indoor scene based on a measured data characteristic model. This method generates a target characteristic library by annotating radar target echo data and extracting the target scattering characteristic model from the target echo, and generates a background noise library based on the background noise. Then, through scene setting and parameter conversion, the target scattering characteristic model of the simulated target is selected from the target characteristic library, and the background noise data is selected from the data noise library. After target characteristic echo modulation and multi-target scene echo generation, the indoor scene construction is completed. This method can fully combine the measured data of the outdoor test with the scene and parameters of the indoor electromagnetic scene to simulate the coherent system radar echo. The simulated scene echo characteristics after coherent accumulation are highly realistic. At the same time, the simulation of the target polarization characteristics in the signal echoes of various polarization states simulated in the indoor field is highly realistic, which can reliably meet the needs of verifying the target recognition algorithm based on polarization information. Therefore, compared with the existing technology, the indoor scene construction method provided by the present invention is more reliable. When simulating target scenes such as ships, angle reflections, and foil strips in the indoor field, the echo characteristics are consistent with the characteristics of the outdoor field collected data, and the range image and Doppler dimension characteristics are highly realistic.

[0148] Those skilled in the art will appreciate that all or part of the process steps of the above-described embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, such as a magnetic disk, an optical disk, a read-only memory, or a random access memory.

[0149] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A method for constructing an interior scene based on a measured data characteristic model, characterized in that: include: Build a variety of field test scenarios and obtain measured radar target echo data in each field test scenario; Generate target characteristic library and background noise library based on the measured radar target echo data in various field test scenarios; According to the scene setting requirements of the indoor scene, a target scattering characteristic model is selected from the target characteristic library, and background noise data is selected from the background noise library; In the indoor scene, according to the scene setting requirements and the target scattering characteristic model of each simulated target, the radar simulated target echo is generated; The background noise data selected from the background noise library is superimposed on the generated radar simulated target echo to obtain the radar simulated echo signal in the indoor scene, thus completing the construction of the indoor scene; Generate radar simulated target returns by doing the following: Generate radar transmission signals according to radar equipment parameters in the scenario setting requirements; Based on the target scattering characteristic model of each simulated target and the radar transmission signal, a radar simulated target echo of the corresponding simulated target is obtained; Get the radar simulated target echo of the simulated target by doing the following: Reconstructing the range-Doppler data of the simulated target in a full polarization state according to the retrieved target scattering characteristic model of the simulated target; Performing decoherent accumulation processing on the reconstructed range-Doppler data of the simulated target in full polarization state to obtain one-dimensional range image data corresponding to the simulated target; According to the radar-target distance in the scenario setting requirements, the one-dimensional range image data of the simulated target is superimposed on the corresponding position of the radar-target distance to form a range image target scattering point set of the simulated target; The target characteristic of the range image target scattering point set of the simulated target is modulated by using the radar transmission signal to generate the radar simulated target echo of the simulated target.

2. The method for constructing an interior scene based on a measured data characteristic model according to claim 1, characterized in that: Generate the target property library by doing the following: Process the measured radar target echo data under each field test scenario to obtain the corresponding range-Doppler data; select the target area on the obtained range-Doppler data and mark the target area's target type, location range, radar equipment parameters, and target parameters; For each target area, all strong scattering points and their characteristic vectors in the target area are extracted to obtain a target scattering characteristic model of the target area; The target type, radar equipment parameters, target parameters and target scattering characteristic model of each target area are summarized to form a target characteristic library.

3. The method for constructing an interior scene based on a measured data characteristic model according to claim 2, characterized in that: Obtain the target scattering characteristic model for each target area by performing the following operations: Extracting range-Doppler data of the target area according to the marked position range of the target area; Obtain the scattering point with the maximum energy in the range-Doppler data of the target area; Determine whether the energy of the scattering point is greater than or equal to the set multiple of the average energy of the background noise in the entire range-Doppler data of the target area, If so, the scattering point is extracted as a strong scattering point, and the characteristic vector of the strong scattering point is obtained; then, the strong scattering point is eliminated from the range-Doppler data of the target area, the range-Doppler data of the target area is updated, and the process jumps to the step of finding the scattering point with the maximum energy; Otherwise, the process of extracting the strong scattering points and their characteristic vectors in the target area ends; All strong scattering points and their characteristic vectors in the target area are summarized to construct a target scattering characteristic model of the target area.

4. The method for constructing an interior scene based on a measured data characteristic model according to claim 3, characterized in that: The characteristic vectors of the strong scattering points include: Coordinates of strong scattering points: distance of the strong scattering point in the target area - distance and Doppler position in Doppler data; Normalized scattering parameter set of strong scattering points: normalized scattering parameters of strong scattering points on the four polarization channels of HH, HV, VH, and VV.

5. The method for constructing an interior scene based on a measured data characteristic model according to claim 4, characterized in that: Generate a background noise library by doing the following: Based on the non-target areas in the measured radar target echo data under various sea conditions, the background noise data under the corresponding sea conditions are formed; the background noise data under all sea conditions are summarized to form a background noise library.

6. The method for constructing an interior scene based on a measured data characteristic model according to claim 5, characterized in that: The scenario setting requirements include: The target type of the simulation target, which can be one or more; Radar equipment parameters, including radar band and polarization state; Scenario environment parameters, including sea conditions, radar equipment altitude, and radar-target distance.

7. The method for constructing an interior scene based on a measured data characteristic model according to claim 6, characterized in that: Selecting a target scattering characteristic model from the target characteristic library includes: Based on the scene environment parameters of the simulation target, obtaining the target parameters of the simulation target; According to the target type, radar band and target parameters of each simulated target, the target scattering characteristic model matching each simulated target is retrieved from the target characteristic library; Select background noise data from the background noise library, including: According to the sea condition information in the scene setting requirements, background noise data matching the sea condition is selected from the background noise library.

8. The method for constructing an interior scene based on a measured data characteristic model according to claim 7, characterized in that: A radar simulated target echo is also generated by performing the following operations: If the scene setting requirements only include one simulated target, the radar simulated target echo of the simulated target is used as the radar simulated target echo in the indoor field scene; otherwise, the radar simulated target echoes of all simulated targets are superimposed with electromagnetic waves to obtain the radar simulated target echo in the indoor field scene.

9. The method for constructing an interior scene based on a measured data characteristic model according to claim 8, characterized in that: The range-Doppler data of the simulated target in all polarization states are reconstructed by performing the following operations: Using the coordinates of each strong scattering point in the target scattering characteristic model of the simulated target as the coordinate points in the reconstructed range-Doppler data; The normalized scattering parameter set of each strong scattering point in the target scattering characteristic model of the simulated target is used as the value of the corresponding coordinate point in the reconstructed range-Doppler data; The rest of the locations without strong scattering points have a value of 0; Thus, the range-Doppler data of the simulated target in full polarization state is reconstructed.

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