A radar echo simulation system

Abstract

The present invention relates to a radar echo simulation system, which belongs to the field of electromagnetic scene simulation technology and solves the technical problems of echo characteristic distortion and poor simulation fidelity of target polarization characteristics in existing internal field electromagnetic scene simulations. The system includes a radar device and a simulated target device; wherein the radar device includes: a radar transmitting module, which generates a radar transmit signal and transmits the radar transmit signal to the simulated target device; a radar antenna, which receives the radar echo simulation signal transmitted by the simulated target device; a signal processing module, which processes the radar transmit signal and the radar echo simulation signal; the simulated target device, which includes: a target characteristic library, which stores multiple target data, each target data consisting of a target type, radar device parameters, target parameters, and a target scattering characteristic model; a target characteristic modulation device, which generates a radar echo simulation signal based on the target characteristic library and the radar transmit signal; and a polarized antenna, which transmits the radar echo simulation signal.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic scene simulation, and in particular to a radar echo simulation system. Background Art

[0002] Existing radar echo simulation methods for indoor field scenarios mainly use signal sources to simulate point targets detected by radar, or modulate the target electromagnetic model to simulate the echo of scene targets with one-dimensional range profile characteristics. However, for the simulation application of false target countermeasure scenarios, this method has the following shortcomings:

[0003] 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.

[0004] 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

[0005] In view of the above analysis, an embodiment of the present invention aims to provide a radar echo simulation system that can solve the technical problems in the prior art of echo characteristic distortion in simulation of internal field electromagnetic scenes and poor fidelity in simulation of target polarization characteristics.

[0006] The present invention discloses a radar echo simulation system, comprising a radar device and a simulated target device; wherein the radar device comprises:

[0007] A radar transmitting module, configured to generate a radar transmitting signal and transmit the radar transmitting signal to the simulated target device;

[0008] A radar antenna, used for receiving a radar echo simulation signal emitted by a simulated target device;

[0009] A signal processing module, configured to process the radar transmission signal and the radar echo simulation signal; the simulated target device comprises:

[0010] The target characteristic library stores multiple target data. Each target data consists of target type, radar equipment parameters, target parameters, and target scattering characteristic model.

[0011] a target characteristic modulation device for generating a radar echo simulation signal based on the target data in the target characteristic library and the radar transmission signal;

[0012] The polarized antenna is used to transmit the radar echo simulation signal.

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

[0014] Furthermore, the radar echo simulation system is located in the electromagnetic environment of an indoor darkroom.

[0015] Furthermore, the target characteristic modulation device includes:

[0016] A scene setting module is used to store scene setting requirements for echo simulation;

[0017] A target scattering characteristic model acquisition module is used to retrieve a matching target scattering characteristic model from the target characteristic library according to the scene setting requirements;

[0018] The radar simulation echo generation module is used to generate a radar echo simulation signal according to the retrieved target scattering characteristic model and the radar transmission signal.

[0019] Furthermore, in the radar simulated target echo generation module, a radar echo simulation signal is generated by performing the following operations:

[0020] 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;

[0021] If the scene setting requirement contains 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; otherwise, the radar simulated target echoes of all simulated targets are superimposed by electromagnetic waves to obtain the radar simulated target echo in the indoor scene;

[0022] Background noise data is superimposed on the generated radar simulated target echo to obtain the radar echo simulation signal in the indoor scene.

[0023] Furthermore, the target scattering characteristic model includes:

[0024] Coordinates of strong scattering points: distance of the strong scattering point in the target area - distance and Doppler position in Doppler data;

[0025] 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.

[0026] Furthermore, in the radar simulation echo generation module, the radar simulation target echo of the corresponding simulated target is obtained by performing the following operations:

[0027] 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;

[0028] 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;

[0029] 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;

[0030] 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.

[0031] Furthermore, in the radar simulation echo generation module, the range-Doppler data of the simulated target in full polarization state is reconstructed by performing the following operations:

[0032] 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;

[0033] The rest of the locations without strong scattering points are set to 0;

[0034] Thus, the range-Doppler data of the simulated target in full polarization state is reconstructed.

[0035] Furthermore, the scene setting requirements include:

[0036] The target type of the simulation target, which can be one or more;

[0037] Radar equipment parameters, including radar band and polarization state;

[0038] Scenario environment parameters, including sea conditions, radar equipment altitude, and radar-target distance.

[0039] Furthermore, in the target scattering characteristic model acquisition module, the matching target scattering characteristic model is retrieved by performing the following operations:

[0040] Based on the scene environment parameters of the simulation target, obtaining the target parameters of the simulation target;

[0041] 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.

[0042] Furthermore, the target scattering characteristic model matching each simulated target is retrieved from the target characteristic library by performing the following operations:

[0043] 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.

[0044] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0045] The radar echo simulation system provided by the present invention has the following advantages:

[0046] 1. The radar device sends a radar transmission signal, and the simulated target device generates a radar echo simulation signal based on the target characteristic library and the radar transmission signal. The radar echo simulation signal is then transmitted and received by the polarized antenna, thereby realizing the radar echo simulation process. The system simulates the target polarization characteristics of the signal echoes in various polarization states in the indoor field with high fidelity, which can reliably meet the requirements of verifying the target recognition algorithm based on polarization information and has high reliability.

[0047] 2. The test shows that when simulating target scenes such as ships, angle reflections, and chaff in the indoor field, the echo characteristics are consistent with the characteristics of the data collected in the outdoor field, and the range image and Doppler dimension characteristics are highly realistic.

[0048] 3. Since the target characteristic library in this embodiment is obtained through field tests, this method can fully combine the measured data of the field tests with the scenes and parameters of the indoor electromagnetic scenes to realize the simulation of the coherent system radar echo. The echo characteristics of the simulated scene after coherent accumulation are highly realistic.

[0049] 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

[0050] 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.

[0051] Figure 1 This is a schematic diagram of the radar echo simulation system structure. DETAILED DESCRIPTION

[0052] 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.

[0053] Example 1

[0054] A specific embodiment of the present invention discloses a radar echo simulation system, the structural diagram of which is shown in FIG. Figure 1As shown, it includes radar equipment and simulated target equipment. The following is an introduction to the composition and working process of the radar equipment and simulated target equipment:

[0055] The radar device in this embodiment includes: a radar transmitting module, a radar antenna and a signal processing module.

[0056] A radar transmitting module is used to generate a radar transmit signal and transmit the radar transmit signal to the simulated target device; it should be noted that the radar transmit signal is determined according to the radar device parameters in the scene setting requirements; the radar device parameters include radar band and polarization state; in this embodiment, the band to which the radar transmit signal belongs is determined according to the radar band in the radar device parameters; the polarization wave of the radar transmit signal is determined according to the polarization state in the radar device 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 fully polarized, the radar transmit signal includes simultaneously transmitted horizontally polarized waves and vertically polarized waves.

[0057] It should also be noted that the radar echo simulation system is located in the electromagnetic environment of an indoor darkroom. In the indoor scene, the radar transmission signal in this embodiment is not actually emitted by the radar antenna, but is transmitted to the simulated target device through other wired or wireless transmission methods.

[0058] In this embodiment, the radar antenna is used to receive a radar echo simulation signal emitted by a simulated target device; upon receiving the radar echo simulation signal, subsequent signal processing operations can be performed. The signal processing module of this embodiment is used to process the radar transmission signal and the radar echo simulation signal; this embodiment does not limit the specific content of the signal processing, and illustratively, radar target recognition and other processing can be performed.

[0059] The simulated target device in this embodiment includes a target characteristic library, a target characteristic modulation device, and a polarized antenna.

[0060] The target characteristic library stores multiple target data items, each of which consists of target type, radar equipment parameters, target parameters, and a target scattering characteristic model. The target scattering characteristic model includes: the coordinates of a strong scattering point: the distance of the strong scattering point in the target area minus the distance and Doppler position in the Doppler data; and the normalized scattering parameter set of the strong scattering point: the normalized scattering parameters of the strong scattering point on the four polarization channels of HH, HV, VH, and VV.

[0061] a target characteristic modulation device for generating a radar echo simulation signal based on the target data of the target characteristic library and the radar transmission signal;

[0062] The polarized antenna is used to transmit the radar echo simulation signal. Here, the polarized antenna is divided into horizontal polarized antenna and vertical polarized antenna to meet the transmission requirements of radar echo simulation signals in different polarization modes.

[0063] The key to realizing the radar echo simulation process lies in the target characteristic modulation device, so this embodiment focuses on this device.

[0064] The target characteristic modulation device includes a scene setting module, a target scattering characteristic model acquisition module and a radar simulation echo generation module. Specifically,

[0065] The scene setting module is used to store the scene setting requirements of the echo simulation. In this embodiment, the scene setting requirements for the indoor scene are set based on the characterization method commonly used in the scene test. Preferably, the scene setting requirements include:

[0066] (1) Target type of simulated target

[0067] The simulation target is one or more;

[0068] (2) Radar equipment parameters

[0069] 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.

[0070] (3) Scene environment parameters

[0071] Scenario environment parameters include sea condition information, altitude of radar equipment, and radar-target distance;

[0072] In particular, the scene environment parameters of ship-type targets also include heading and speed;

[0073] The scene environment parameters of the chaff target also include the altitude of the chaff target.

[0074] A target scattering characteristic model acquisition module is configured to retrieve a matching target scattering characteristic model from the target characteristic library according to the scenario setting requirements. In the target scattering characteristic model acquisition module, the matching target scattering characteristic model is retrieved by performing the following operations:

[0075] Step 1-1: Based on the scene environment parameters of the simulation target, obtain the target parameters of the simulation target;

[0076] The target parameters are the same as those in the target characteristic library;

[0077] (1) Grazing angle

[0078] 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.

[0079] (2) Observe the side angle

[0080] 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.

[0081] (3) Radial velocity

[0082] The radial velocity is obtained by calculating the ship's heading and speed.

[0083] Step 1-2: 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.

[0084] It should be clarified that the matching in steps 1-2 refers to searching the target characteristic library for a piece of target data that matches the target type and radar band of the simulated target, and whose target parameters meet a preset threshold deviation requirement, and using the target scattering characteristic model in this piece of target data as the target scattering characteristic model of the simulated target. Preferably, the target parameters meeting the preset threshold deviation requirement 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 must meet the threshold deviation for that parameter.

[0085] The radar simulation echo generation module is used to generate a radar echo simulation signal according to the retrieved target scattering characteristic model and the radar transmission signal.

[0086] Preferably, in the radar simulated target echo generation module, the radar echo simulation signal is generated by performing the following operations:

[0087] Step 2-1: Based on the target scattering characteristic model of each simulated target and the radar transmission signal, obtain the radar simulated target echo of the corresponding simulated target;

[0088] For each simulated target, obtain the radar simulated target echo of the simulated target by performing the following operations:

[0089] Step 2-1-1: 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,

[0090] 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;

[0091] 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;

[0092] The rest of the locations without strong scattering points are set to 0;

[0093] Thus, the range-Doppler data of the simulated target in full polarization state is reconstructed;

[0094] Step 2-1-2: Perform decoherent accumulation processing on the reconstructed range-Doppler data of the simulated target in the full polarization state to obtain the one-dimensional range image data corresponding to the simulated target;

[0095] Step 2-1-3: 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 the range image target scattering point set of the simulated target.

[0096] Step 2-1-4: Use the radar transmission signal to modulate the target characteristic of the range image target scattering point set of the simulated target to generate the radar simulated target echo of the simulated target;

[0097] The formula for target characteristic echo modulation is expressed as:

[0098]

[0099]

[0100] 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.

[0101] Step 2-2: If the scene setting requirement only includes one simulated target, the radar simulated target echo of the simulated target is used as the radar simulated target echo in the indoor scene;

[0102] 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;

[0103] 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:

[0104]

[0105] 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.

[0106] Step 2-3: Superimpose background noise data on the generated radar simulated target echo to obtain a radar echo simulation signal in an indoor scene.

[0107] 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 echo simulation signal in the indoor scene is obtained after superposition, which is expressed as follows:

[0108] r H =Rt H +rn H

[0109] r V =Rt V +rn V

[0110] Among them, r H 、r V Respectively represent the horizontal polarization radar echo simulation signal and vertical polarization radar echo simulation signal in the indoor scene; rnH 、rn V Represent the background noise data in the horizontal polarization direction and the vertical polarization direction respectively.

[0111] To better simulate background noise, the target device can also include a background noise library to store background noise data for different sea conditions. When superimposing background noise, based on the sea condition information specified in the scenario setup requirements, background noise data matching the sea condition is selected from the background noise library and used for noise superposition.

[0112] After the target characteristic modulation module generates a radar echo simulation signal, the radar echo simulation signal is sent to the polarized antenna, and the polarized antenna transmits the signal.

[0113] Specifically, the polarized antenna includes a vertically polarized antenna and a horizontally polarized antenna. During the radar echo simulation signal transmission process, the vertically polarized antenna transmits a vertically polarized radar echo simulation signal, and the horizontally polarized antenna transmits a horizontally polarized radar echo simulation signal.

[0114] The radar antenna in the radar equipment receives the above radar echo simulation signal and sends the signal to the signal processing module for data processing to acquire the target.

[0115] In summary, this embodiment provides a radar echo simulation system that generates a radar echo simulation signal from a radar device, simulates a target device based on a target characteristic library and the radar transmit signal, and transmits the radar echo simulation signal through a polarized antenna and receives the radar echo simulation signal through a radar antenna, thereby realizing the radar echo simulation process. The system simulates the target polarization characteristics of signal echoes in various polarization states in the indoor field with high fidelity, reliably meeting the requirements for verifying target recognition algorithms based on polarization information, and has high reliability. Experiments have shown that when simulating target scenes such as ships, angular reflections, and chaff 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. Because the target characteristic library in this embodiment is obtained through outdoor testing, this method can fully combine the measured data of the outdoor test with the scene and parameters of the indoor electromagnetic scene, realizing the simulation of coherent system radar echoes. The echo characteristics of the simulated scene after coherent accumulation are highly realistic.

[0116] Example 2

[0117] To facilitate those skilled in the art to better implement the solution in Example 1, Example 2 of the present invention provides a process for generating a target characteristic library and a background noise library for reference by relevant technical personnel. Specifically, it includes:

[0118] Step S1: construct multiple field test scenarios and obtain measured radar target echo data in each field test scenario;

[0119] 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.

[0120] Step S2: Process the measured radar target echo data in each field test scenario separately to obtain the corresponding range-Doppler data; select the target area on the obtained range-Doppler data, and mark the target type, location range, radar equipment parameters, and target parameters of the target area.

[0121] 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.

[0122] 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,

[0123] 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.

[0124] Position range, which indicates the coordinate information of the target area in the range-Doppler data;

[0125] Radar equipment parameters, including radar band and polarization state.

[0126] 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.

[0127] Step S3: 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;

[0128] Specifically, all strong scattering points in each target area are extracted by performing the following operations:

[0129] Step S31: extracting the range-Doppler data of the target area according to the marked position range of the target area;

[0130] Step S32: obtaining the scattering point with the maximum energy in the range-Doppler data of the target area;

[0131] Step S33: 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).

[0132] 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 S32, i.e., the scattering point with the maximum energy is searched again in the updated range-Doppler data of the target area.

[0133] Otherwise, the process of extracting the strong scattering points and their characteristic vectors in the target area ends.

[0134] 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.

[0135] In this embodiment, the extracted characteristic vectors of the strong scattering points include:

[0136] Coordinates of strong scattering points: distance of the strong scattering point in the target area - distance and Doppler position in Doppler data;

[0137] 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.

[0138] 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:

[0139] (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;

[0140] (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;

[0141] (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.

[0142] In this process, the sensor parameters and scene parameters can be completely eliminated through the RCS normalization method.

[0143] 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.

[0144] Step S4: Summarize the target type, radar equipment parameters, target parameters, and target scattering characteristic model of each target area to form a target characteristic library;

[0145] For example, in the target feature library, some examples are represented as shown in Table 1.

[0146] Table 1 Example of some contents of target characteristic library

[0147]

[0148]

[0149] Step S5: 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.

[0150] By extracting the characteristics of measured data to construct a target scattering characteristic model, the radar target echo range image and Doppler dimension characteristics are more realistic, which can meet the requirements of the high-resolution radar recognition performance test environment in indoor field scenarios.

[0151] 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.

[0152] 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 radar echo simulation system, characterized in that: The invention comprises a radar device and a simulated target device; wherein the radar device comprises: A radar transmitting module, configured to generate a radar transmitting signal and transmit the radar transmitting signal to the simulated target device; A radar antenna, used for receiving a radar echo simulation signal emitted by a simulated target device; A signal processing module, configured to process the radar transmission signal and the radar echo simulation signal; the simulated target device comprises: The target characteristic library stores multiple target data. Each target data consists of target type, radar equipment parameters, target parameters, and target scattering characteristic model. a target characteristic modulation device for generating a radar echo simulation signal based on the target data in the target characteristic library and the radar transmission signal; a polarized antenna, configured to transmit the radar echo simulation signal; The target characteristic modulation device comprises: A scene setting module is used to store scene setting requirements for echo simulation; A target scattering characteristic model acquisition module is used to retrieve a matching target scattering characteristic model from the target characteristic library according to the scene setting requirements; A radar simulation echo generation module is used to generate a radar echo simulation signal based on the retrieved target scattering characteristic model and the radar transmission signal; In the radar simulated target echo generation module, based on the target scattering characteristic model of each simulated target and the radar transmission signal, the following operations are performed to obtain the radar simulated target echo of the corresponding simulated target: 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 radar echo simulation system according to claim 1, characterized in that: The radar echo simulation system is located in the electromagnetic environment of an indoor darkroom.

3. The radar echo simulation system according to claim 1 or 2, characterized in that: In the radar simulated target echo generation module, a radar echo simulation signal is generated by performing the following operations: 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; If the scene setting requirement contains 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; otherwise, the radar simulated target echoes of all simulated targets are superimposed by electromagnetic waves to obtain the radar simulated target echo in the indoor scene; Background noise data is superimposed on the generated radar simulated target echo to obtain the radar echo simulation signal in the indoor scene.

4. The radar echo simulation system according to claim 3, characterized in that: The target scattering characteristic model includes: 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 radar echo simulation system according to claim 4, characterized in that: In the radar simulation echo generation module, the range-Doppler data of the simulated target in full polarization state is reconstructed by performing the following operations: 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.

6. The radar echo simulation system according to claim 1, 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 radar echo simulation system according to claim 6, characterized in that: In the target scattering characteristic model acquisition module, the matching target scattering characteristic model is retrieved by performing the following operations: 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.

8. The radar echo simulation system according to claim 1, characterized in that: The target scattering characteristic model matching each simulated target is retrieved from the target characteristic library by performing the following operations: 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.

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