A distributed radar anti-stealth capability quantification method based on fusion discovery probability

Abstract

The application discloses a kind of distributed radar anti-stealth capability quantization methods based on fusion discovery probability, it is related to radar detection technical field.It includes: obtaining the discovery probability of each radar transceiver combination aircraft;The discovery probability of each radar transceiver combination is fused;Re-select aircraft heading angle, until all possible heading angles are traversed;Select the minimum value of the fusion discovery probability under all heading angles as the anti-stealth fusion discovery probability on the current grid position;Threshold meets grid is included in anti-stealth range;Re-select grid position, until all the grids in monitoring area are traversed;The ratio of the number of anti-stealth range grids to the number of monitoring range grids is calculated, and the anti-stealth capability of the radar system is quantified.The present application fully considers the RCS dramatic fluctuation stealth aircraft rotating maneuvering scene, can intuitively and accurately describe the distributed radar system detection stealth aircraft capability, and provide guidance for distributed radar system optimization station.

Description

Technical Field

[0001] This invention relates to the field of radar detection technology, and in particular to a distributed radar anti-stealth capability quantification method based on fused detection probability. Background Technology

[0002] Stealth aircraft, by reducing their radar cross-section (RCS) value, lower the probability of radar detection, making them a significant threat weapon for penetrating defense networks and reaching deep into enemy territory. Distributed radar systems, illuminating stealth aircraft from different directions, can effectively improve the ability to detect stealth targets. However, current assessments of the anti-stealth capabilities of distributed radar systems mainly focus on the use of technical means, lacking quantitative characterization methods for the anti-stealth capabilities of distributed radar systems after fusion processing under certain deployment conditions. This makes it difficult to intuitively and quickly describe the ability of distributed radar to detect stealth aircraft. On the other hand, existing literature on the anti-stealth capabilities of distributed radar systems mostly considers scenarios involving the inherent flight path or specific flight direction of stealth aircraft, without further considering scenarios where aircraft penetrate defenses in different headings, making it difficult to comprehensively and accurately quantify the system's anti-stealth capabilities. Summary of the Invention

[0003] This invention addresses the shortcomings mentioned above by providing a quantitative characterization method for the anti-stealth capability of a distributed radar system based on fused detection probabilities. This invention fully considers the scenario of stealth aircraft maneuvering with drastically fluctuating RCS (Radar Cross Section), and utilizes data fusion criteria to fuse the detection probabilities of each transmitting and receiving radar, thus achieving a quantitative characterization of the anti-stealth capability of the distributed radar system. This quantitative characterization can intuitively and comprehensively describe the anti-stealth capability of the distributed radar system and can provide guidance for the optimized deployment of distributed radar systems.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A distributed radar anti-stealth capability quantification method based on fused detection probability includes the following steps:

[0006] Step 1: Determine the basic parameters of the distributed radar system, including the number of radar stations, their locations, transmission power, operating wavelength, antenna gain, single-station false alarm probability, noise power, as well as the size and number of grids used to divide the surveillance area, the aircraft heading angle range, and the aircraft's bistatic radar cross section.

[0007] Step 2: Based on the basic parameters determined in Step 1, according to the set grid position and aircraft heading angle, obtain the detection probability of each radar transceiver combination for the aircraft at the set grid position and heading angle.

[0008] Step 3: The rank-K fusion criterion is used to fuse the detection probability of each radar transceiver combination for the aircraft at the current position and current heading angle, so as to obtain the fused detection probability of the distributed radar system for the aircraft at the current grid position and current heading angle.

[0009] Step 4: Select the aircraft heading angle again, return to step 2, until all possible heading angles of the aircraft have been traversed; select the value with the lowest fusion detection probability under all heading angles of the aircraft as the anti-stealth fusion detection probability at the current grid position;

[0010] Step 5: Compare the anti-stealth fusion detection probability at the current grid location with the detection probability threshold, and include grids with an anti-stealth fusion detection probability greater than or equal to the detection probability threshold in the anti-stealth range;

[0011] Step 6: Select a new grid position and return to Step 2 until all grids in the monitored area have been traversed to obtain the total anti-stealth range within the monitored area; then, the anti-stealth capability of the distributed radar system is quantitatively evaluated by calculating the ratio of the number of anti-stealth range grids to the number of monitored range grids.

[0012] Furthermore, step 2 specifically includes the following steps:

[0013] (2a) Each time, two radar stations are selected from N radar stations for one-to-one transmission and one-to-reception, or one radar station performs self-transmission and self-reception. There are a total of N 2 A variety of transceiver combinations are used; based on the set grid position and aircraft heading angle, the relative incident distance, incident angle, receiving distance, and receiving angle of each radar transceiver combination with the aircraft at the current grid position and current heading angle are obtained;

[0014] (2b) Obtain the cross section of the aircraft relative to each radar transceiver combination at the current grid position and current heading angle based on the incident angle and the receiving angle;

[0015] (2c) Based on the scattering cross-section, incident distance, receiving distance and radar characteristic parameters of the aircraft and each radar transceiver combination, the received echo signal-to-noise ratio of each radar transceiver combination is obtained.

[0016] (2d) Based on the false alarm probability and the signal-to-noise ratio of the received echo of each radar transceiver combination, the detection probability of each radar transceiver combination for the aircraft at the current grid position and current heading angle is obtained.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. This invention fully considers the scenario of stealth aircraft rotating and maneuvering with drastic RCS fluctuations, and uses data fusion criteria to fuse the detection probability of each transmitting and receiving radar, thereby realizing the quantitative characterization of the anti-stealth capability of the distributed radar system.

[0019] 2. The method of the present invention can intuitively and accurately describe the anti-stealth capability of a distributed radar system, solve the problem of distributed radar detecting stealth aircraft, and provide guidance for optimizing the deployment of distributed radar systems. Attached Figure Description

[0020] Figure 1 This is a flowchart of an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of a distributed radar deployment scenario according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the anti-stealth range of a distributed radar system using the rank-1 fusion rule in an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram of the anti-stealth range of a distributed radar system using the rank-2 fusion rule in an embodiment of the present invention. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0025] A quantitative characterization method for the anti-stealth capability of a distributed radar system based on fused detection probability is proposed. This method obtains the detection probability of each radar transceiver combination in the distributed radar system at the current position and angle of the aircraft, based on radar characteristic parameters, stealth aircraft characteristic parameters, set grid positions, and aircraft rotation angles. Then, the detection probabilities of each radar transceiver combination are fused using the rank-K fusion criterion to obtain the fused detection probability. Next, all possible heading angles of the aircraft at the current position are traversed, and the value with the minimum fused detection probability at all heading angles is selected as the anti-stealth fused detection probability at the current grid position. Then, grids with anti-stealth fused detection probabilities greater than or equal to the detection probability threshold are included in the anti-stealth range of the distributed radar system. Then, all grids in the monitoring area are traversed again, and the above operations are repeated to obtain the total anti-stealth range within the monitoring area. Finally, the anti-stealth capability of the distributed radar system is quantified by calculating the ratio of the anti-stealth range to the monitoring range.

[0026] Specifically, it includes the following steps:

[0027] Step 1: Determine the basic parameters of the distributed radar system, including the number of radar stations, their locations, transmit power, operating wavelength, antenna gain, single-station false alarm probability, noise power, as well as the size and number of grids used to divide the surveillance area, the aircraft heading angle range, and the aircraft's bistatic RCS value.

[0028] Step 2: Based on the basic parameters determined in Step 1, according to the set grid position and aircraft heading angle, obtain the probability of each radar transceiver unit detecting the aircraft at the set heading angle at the grid position.

[0029] Step 3: Use the rank-K fusion criterion to fuse the aircraft detection probabilities of each radar transceiver combination at the current position and current heading angle, and obtain the fused detection probability of the distributed radar system at the current grid position and current heading angle.

[0030] Step 4: Reselect the aircraft heading angle and return to Step 2 until all possible heading angles have been traversed. Select the value with the minimum fusion detection probability among all heading angles as the anti-stealth fusion detection probability at the current grid position.

[0031] Step 5: Compare the detection probability of the anti-stealth fusion at the current grid location with the detection probability threshold, and include grids with an anti-stealth fusion detection probability greater than or equal to the detection probability threshold within the anti-stealth range.

[0032] Step 6: Reselect the grid position and return to Step 2 until all grids in the monitored area have been traversed, obtaining the total anti-stealth range within the monitored area. Then, quantitatively evaluate the anti-stealth capability of the distributed radar system by calculating the ratio of the number of grids in the anti-stealth range to the number of grids in the monitored area. The larger the ratio of the anti-stealth range to the monitored area, the stronger the anti-stealth capability of the distributed radar system in that monitored area.

[0033] Specifically, step 2 includes the following steps:

[0034] (2a) Each time, two radar stations are selected from N radar stations for one-to-one transmission and one-to-reception, or one radar station is selected for self-transmission and self-reception. There are a total of N 2 Each radar transceiver combination is configured with a set grid position and aircraft heading angle. The relative incident distance, incident angle, receiving distance, and receiving angle of each radar transceiver combination to the aircraft at the current grid position and heading angle are then determined.

[0035] (2b) Obtain the cross section of the aircraft relative to each radar transceiver combination at the current grid position and current heading angle based on the incident angle and the receiving angle.

[0036] (2c) Based on the scattering cross-section, incident distance, receiving distance and radar characteristic parameters of the aircraft and each radar transceiver combination, the received echo signal-to-noise ratio of each radar transceiver combination is obtained.

[0037] (2d) Based on the false alarm probability and the signal-to-noise ratio of the received echo of each radar transceiver combination, the detection probability of each radar transceiver combination for the aircraft at the current grid position and current heading angle is obtained.

[0038] Here is a more specific example:

[0039] like Figure 1 As shown, a quantitative characterization method for the anti-stealth capability of a distributed radar system based on fused detection probability specifically includes the following steps:

[0040] Step 1: Determine the basic parameters of the distributed radar system, including the number of radar stations, their locations, transmit power, operating wavelength, antenna gain, single-station false alarm probability, noise power, as well as the size and number of grids used to divide the surveillance area, the aircraft's heading angle range, and the aircraft's bistatic RCS value.

[0041] like Figure 2 As shown, it is assumed that the deployment area and monitoring area of ​​the distributed radar system are set in a unified two-dimensional plane coordinate system. The distributed radar network system includes N radar stations and L monitoring area grids, and the coordinates of the nth radar station are denoted as . The grid location of the l-th monitoring area is (x l ,y l The grid size is S. Assume the aircraft is on the monitored grid and its heading angle is some angle θ between -θ and θ'. m .

[0042] The aircraft could be an F-22 stealth fighter, and the simulation uses the bistatic RCS value of the F-22 with HH polarization.

[0043] When the aircraft's heading angle is 0°, the aircraft's nose points towards the negative X-axis. A rotation angle of -θ indicates that the aircraft's nose rotates by an angle θ from the negative X-axis towards the negative Y-axis. A rotation angle of θ indicates that the aircraft's nose rotates by an angle θ from the negative X-axis towards the positive Y-axis.

[0044] The number of radar stations can be assumed to be 8, located at (0km, -87.5km), (0km, -62.5km), (0km, -37.5km), (0km, -12.5km), (0km, 12.5km), (0km, 37.5km), (0km, 62.5km), and (0km, 87.5km). The X-axis range of the surveillance area is 0km to 180km, and the Y-axis range is -180km to 180km. The surveillance area is divided into a grid, with each grid measuring 10km x 10km, for a total of 703 grids. The aircraft heading angle range is -90° to 90°, with an angular resolution of 1°, for a total of 181 angles. The transmit power of a single radar station is 480kW, the operating wavelength is 0.23m, the antenna gain is 16.8dB, and the noise power is kT. o B n k represents the Boltzmann constant, T o Standard room temperature is typically 290K, Bn This represents the noise bandwidth, which can be taken as 50Hz. The false alarm probability is 10. -6 .

[0045] Suppose the plane is currently on the l-th grid, l=1, and the plane has rotated to the m-th angle, m=1.

[0046] Step 2: Based on the basic parameters determined in Step 1, according to the set grid position and aircraft heading angle, obtain the detection probability of each radar transceiver combination for the aircraft at the set grid position and heading angle.

[0047] In this embodiment, each time two radar stations are selected from N radar stations for one-to-one transmission and one-to-reception or one radar station for self-transmission and self-reception, for a total of N. 2 Type of receiving and sending combination.

[0048] According to the set grid position (x l ,y l ) and aircraft heading angle θ m The relative incident distance R between the i-th radar transceiver combination and the aircraft at the current grid position and current heading angle is obtained. tlmi Angle of incidence Reception distance R rlmi and receiving angle

[0049] According to the incident angle and receiving angle Obtain the cross-sectional area δ of the aircraft relative to the i-th radar transceiver combination at the current grid position and current heading angle. tlmi,rlmi .

[0050] Based on the scattering cross-section δ of the aircraft and each radar transceiver combination tlmi,rlmi Incident distance R tlmi Reception distance R rlmi Based on the radar characteristic parameters, the received echo signal-to-noise ratio ξ of the i-th radar transceiver combination is obtained. lmi .

[0051] The formula for calculating the received echo signal-to-noise ratio of the i-th radar transceiver combination is as follows:

[0052]

[0053] Among them, P t G represents radar transmit power. t and G r λ represents the transmit antenna gain and receive antenna gain, respectively, and λ represents the wavelength of the electromagnetic wave emitted by the radar. o B n The noise power is given, and the noise figure is ignored. k represents the Boltzmann constant, and T... oStandard room temperature is typically 290K, B n This represents the noise bandwidth.

[0054] Based on the false alarm probability P fa The signal-to-noise ratio ξ of the received echo of the i-th radar transceiver combination lmi The probability P of the i-th radar transceiver combination detecting the aircraft at the current grid position and current heading angle is obtained. lmi .

[0055] The formula for calculating the detection probability of the i-th radar transceiver combination is as follows:

[0056]

[0057] Where Q represents the Markum function, γ T =-ln(P fa Based on the above formula, calculate the detection probability for each radar transceiver combination.

[0058] Step 3: Use the rank-K fusion criterion to fuse the detection probabilities of each radar transceiver combination for the aircraft at the current position and current heading angle, and obtain the fused detection probability of the distributed radar system for the aircraft at the current grid position and current heading angle.

[0059] According to the rank-K fusion criterion, a distributed radar system consisting of N radar stations contains N 2 The distributed radar system is determined to detect the target when the number of radar transceiver combinations of the aircraft is greater than or equal to the detection threshold K.

[0060] Based on the detection probability P of the i-th radar transceiver combination obtained in step 2 lmi Generate local decision value d i The judgment is based on whether the detection probability is greater than or equal to the detection probability threshold; if it is greater than or equal to the detection probability threshold, the aircraft is detected, d. i If d is 1, otherwise d i The result is 0. Then, the judgment results of each radar transceiver combination are fused together to obtain the global decision value D, where D = d1 + d2 + ... + d N2 When D≥K, it is determined that the distributed radar system has detected the aircraft at the current position and current heading angle; otherwise, it is determined that the distributed radar system has not detected the aircraft at the current position and current heading angle.

[0061] Therefore, the probability of fusion detection by a distributed radar system is:

[0062]

[0063] Similarly, the fusion false alarm probability of a distributed radar system is:

[0064]

[0065] Among them, P fai Let be the false alarm probability of the i-th radar transceiver combination. When the false alarm probabilities of all radar transceiver combinations are equal, the false alarm probability of the distributed radar system is:

[0066]

[0067] In this embodiment, each radar transceiver unit uses the same performance parameters, and the false alarm probability is taken as P. fa =10 -6 .

[0068] Step 4: Reselect the aircraft heading angle, i.e., let m = m + 1, and return to Step 2 until all possible heading angles of the aircraft have been traversed, i.e., m > 181. Select the value with the minimum fusion detection probability under all heading angles of the aircraft as the anti-stealth fusion detection probability P at the current grid position. Dl .

[0069] The probability P of anti-stealth fusion detection at the current grid location Dl The calculation formula is as follows:

[0070]

[0071] Step 5: Blend the anti-stealth detection probability P at the current grid location. Dl With the discovery probability threshold P Dmin By comparison, grids l whose anti-stealth fusion detection probability is greater than or equal to the detection probability threshold are included in the anti-stealth range.

[0072] Step 6: Reselect the grid position, i.e., let l = l + 1, and return to step 2 until all grids in the monitored area have been traversed, i.e., l > L. All grids within the monitored area whose anti-stealth fusion detection probability is greater than or equal to the detection probability threshold constitute the anti-stealth range of the distributed radar system, such as... Figure 3 As shown. The number of grid cells included in the anti-stealth range. Then calculate the ratio of the anti-stealth range to the surveillance range. To quantify the anti-stealth capability of distributed radar systems.

[0073] Figure 3 The fusion detection probability is obtained by using the rank-1 fusion rule and compared with the detection probability threshold of 0.8. The resulting anti-stealth range has a corresponding fusion false alarm probability of 6.4e-5. The number of grids belonging to the anti-stealth range is 507, and the ratio of the anti-stealth range to the surveillance range is 0.72. This indicates that the anti-stealth capability of the distributed radar system in the surveillance area is quantified to 0.72.

[0074] Figure 4The fusion detection probability is obtained by using the rank-2 fusion rule and compared with the detection probability threshold of 0.8 to obtain the anti-stealth range. The corresponding fusion false alarm probability is 2e-9, the number of grids belonging to the anti-stealth range is 451, and the ratio of the anti-stealth range to the surveillance range is 0.64, indicating that the anti-stealth capability of the distributed radar system in the surveillance area is quantified as 0.64.

[0075] In summary, this invention fully considers the scenario of stealth aircraft rotating and maneuvering with drastic RCS fluctuations. It can intuitively and accurately describe the ability of distributed radar systems to detect stealth aircraft, solve the problem of distributed radar detection of stealth aircraft, and provide guidance for the optimized deployment of distributed radar systems.

Claims

1. A distributed radar anti-stealth capability quantification method based on fused detection probability, characterized in that, Includes the following steps: Step 1: Determine the basic parameters of the distributed radar system, including the number of radar stations, their locations, transmission power, operating wavelength, antenna gain, single-station false alarm probability, noise power, as well as the size and number of grids used to divide the surveillance area, the aircraft heading angle range, and the aircraft's bistatic radar cross section. Step 2: Based on the basic parameters determined in Step 1, according to the set grid position and aircraft heading angle, obtain the detection probability of each radar transceiver combination for the aircraft at the set grid position and heading angle. Step 3: The rank-K fusion criterion is used to fuse the detection probability of each radar transceiver combination for the aircraft at the current position and current heading angle, so as to obtain the fused detection probability of the distributed radar system for the aircraft at the current grid position and current heading angle. Step 4: Select the aircraft heading angle again, return to step 2, and repeat until all possible heading angles of the aircraft have been traversed. The value with the lowest probability of detection by fusion under all heading angles of the aircraft is selected as the anti-stealth fusion detection probability at the current grid position; Step 5: Compare the anti-stealth fusion detection probability at the current grid location with the detection probability threshold, and include grids with an anti-stealth fusion detection probability greater than or equal to the detection probability threshold in the anti-stealth range; Step 6: Select a new grid position and return to Step 2 until all grids in the monitored area have been traversed to obtain the total anti-stealth range within the monitored area; then, the anti-stealth capability of the distributed radar system is quantitatively evaluated by calculating the ratio of the number of anti-stealth range grids to the number of monitored range grids.

2. The distributed radar anti-stealth capability quantification method based on fusion detection probability according to claim 1, characterized in that, Step 2 specifically includes the following steps: (2a) Each time, two radar stations are selected from N radar stations for one-to-one transmission and one-to-reception, or one radar station performs self-transmission and self-reception. There are a total of N 2 A variety of transceiver combinations are used; based on the set grid position and aircraft heading angle, the relative incident distance, incident angle, receiving distance, and receiving angle of each radar transceiver combination with the aircraft at the current grid position and current heading angle are obtained; (2b) Obtain the cross section of the aircraft relative to each radar transceiver combination at the current grid position and current heading angle based on the incident angle and the receiving angle; (2c) Based on the scattering cross-section, incident distance, receiving distance and radar characteristic parameters of the aircraft and each radar transceiver combination, the received echo signal-to-noise ratio of each radar transceiver combination is obtained. (2d) Based on the false alarm probability and the signal-to-noise ratio of the received echo of each radar transceiver combination, the detection probability of each radar transceiver combination for the aircraft at the current grid position and current heading angle is obtained.

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