Networking radar interception probability performance evaluation method and system

Abstract

The invention belongs to but not limited to the technical field of radar signal processing, and discloses a networking radar interception probability performance evaluation method and system, and the method comprises the steps: building a networking radar system model which comprises a plurality of transmitting nodes; calculating the radiation power: calculating the radiation power of each transmitting node at each position in the space through a radar equation; calculating the critical signal-to-noise ratio of the interception receiver; obtaining the critical signal-to-noise ratio of the interception signal of the interception receiver according to the detection probability and the false alarm probability of the interception receiver; and calculating the equivalent radius of the easily intercepted area: obtaining the easily intercepted area of the networking radar according to the radiation power and the critical signal-to-noise ratio, and then calculating the equivalent radius of the corresponding easily intercepted area. The low-interception performance evaluation index is clear in physical significance and can serve as a target function or a constraint condition to optimize radar parameters in low-interception probability radar design, and the probability that a radar system is intercepted is reduced.

Description

Technical Field

[0001] The present invention belongs to but is not limited to the field of radar signal processing technology, and in particular relates to a method and system for evaluating the intercept probability performance of a networked radar. Background Art

[0002] With the increasing complexity of battlefield environment and the development of electronic technology, the survivability of radar in actual combat is seriously threatened. To ensure the survivability of radar, low probability of intercept (LPI) technology has been widely used and developed. In order to obtain good detection performance and anti-interception performance, it is usually necessary to use LPI technology to optimize radar resources. A networked radar system composed of multiple radars has stronger detection performance and anti-interception performance. At present, the LPI performance evaluation of networked radars is still a problem worthy of attention. The existing networked radar LPI evaluation methods mainly include interception factor, interception probability and radiation power. The interception factor of the networked radar is calculated by equivalently treating the networked radar as a single radar, and the LPI performance is achieved by minimizing the interception factor of the networked radar. However, considering the distribution of radars in the networked system, it is no longer reasonable to simply equate the networked radar to a single radar from a physical point of view. The interception probability of the networked radar is a function of the interceptor, and usually requires prior information on the parameters and position of the interceptor, which is not easy to obtain in practical applications. Some methods use the radiation power of networked radars as an LPI performance evaluation indicator. Under the premise of meeting the detection performance, the radiation power of networked radars is minimized to achieve a lower interception probability. The reduction of the radiation power of networked radars will lead to a decrease in the propagation intensity of the signal in space, thereby reducing the probability of being intercepted by enemy reconnaissance aircraft. However, since the radiation power of networked radars is an indirect measure of LPI performance, it is difficult to provide quantitative and intuitive evaluation.

[0003] In view of the above analysis, the technical problems that urgently need to be solved in the existing technology are: the existing networked radar intercept probability performance evaluation method lacks consideration of physical meaning and obtainable prior information, and is difficult to adapt to the performance evaluation of low interception radar when the radar is networked. There is a lack of a physically meaningful, quantifiable, and intuitive networked radar intercept probability performance evaluation. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a method for evaluating the intercept probability performance of a networked radar, which can evaluate the low intercept probability performance of a networked radar and is a physically meaningful and quantifiable performance measurement method for intuitively characterizing the low intercept probability performance.

[0005] The present invention is implemented in this way: a network radar intercept probability performance evaluation method comprises the following steps:

[0006] Step 1: Establish a networked radar system model, where the networked radar system includes multiple transmitting nodes;

[0007] Step 2: Calculate the radiation power: Calculate the radiation power of each transmitting node at each position in space using the radar equation;

[0008] Step 3, calculating the critical signal-to-noise ratio of the interception receiver: according to the detection probability and false alarm probability of the interception machine, the critical signal-to-noise ratio of the interception machine's intercepted signal is obtained;

[0009] Step 4: Calculate the equivalent radius of the easy-to-intercept area: According to the radiation power and the critical signal-to-noise ratio, obtain the easy-to-intercept area of ​​the networked radar, and then calculate the equivalent radius of the corresponding easy-to-intercept area.

[0010] Furthermore, in the step 1, the transmitting node of the radar network is m, and the average transmitting power of the transmitting node m at time t is P Am,t .

[0011] Furthermore, in step 2, it is assumed that each transmitting node is a MIMO radar. For transmitting node m, the distance is R Im The radiated power at can be expressed as:

[0012]

[0013] Furthermore, the critical signal-to-noise ratio SNR of the intercepted signal in step 3 is Ith , the detection probability of the interceptor p D and false alarm probability p F The relationship can be expressed as:

[0014]

[0015] The critical signal-to-noise ratio (SNR) of the interceptor signal can be obtained based on the detection probability and false alarm probability. Ith .

[0016] Further, in step 4, the easily intercepted area A of the networked radar at time t t for:

[0017]

[0018] Where Area represents the area that meets the conditions. Where N I represents the noise power of the interceptor, which can be specifically expressed as:

[0019] N I =KT I F I B I (4)

[0020] K is the Boltzmann constant. T I , F I and B I are the absolute temperature, noise coefficient and bandwidth of the interceptor respectively. Then according to the easy interception area A of the networked radar t Calculate the equivalent radius of the easily intercepted area NCEVR t , which can be specifically expressed as:

[0021]

[0022] Another object of the present invention is to provide a networked radar intercept probability performance evaluation system of a networked radar intercept probability performance evaluation method, comprising:

[0023] A networked radar system building module, used to establish a networked radar system consisting of multiple transmitting nodes;

[0024] The radiation power calculation module is used to calculate the radiation power of each transmitting node at each position in space through the radar equation;

[0025] A critical signal-to-noise ratio calculation module is used to calculate the critical signal-to-noise ratio required for the interception receiver to intercept the signal under certain detection probability and false alarm probability conditions;

[0026] The equivalent radius calculation module is used to calculate the easy-to-intercept area of ​​the networked radar according to the radiation power and the critical signal-to-noise ratio, and then calculate the equivalent radius of the corresponding easy-to-intercept area.

[0027] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the networked radar intercept probability performance evaluation method.

[0028] Another object of the present invention is to provide a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the processor executes the steps of the networked radar intercept probability performance evaluation method.

[0029] Another object of the present invention is to provide an information data processing terminal, which includes the networked radar intercept probability performance evaluation system.

[0030] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0031] First, the existing low probability of intercept networked radar lacks a physically meaningful, quantifiable, and intuitive intercept probability performance evaluation method. To address this problem, the present invention combines the critical signal-to-noise ratio of the intercept receiver and the easy intercept area, calculates the easy intercept area equivalent radius through the networked radar system model, and thus proposes a low probability of intercept performance evaluation method suitable for networked radars.

[0032] The low interception performance evaluation method of the present invention has clear physical meaning, can be used as a quantitative index of an objective function or constraint condition to optimize radar parameters in the design of a low probability of interception radar, and can be used to improve the anti-interception performance of a radar system.

[0033] Second, the technical solution of the present invention fills the technical gap of the equivalent radius of the easy-to-intercept area in radar networking: the conventional easy-to-intercept area equivalent radius is calculated from the easy-to-intercept area of ​​a single radar. However, when radars are networked, the interaction between multiple radars and the overlap of easy-to-intercept areas must be considered, so the conventional easy-to-intercept area equivalent radius and its simple superposition are no longer applicable. This patent proposes an easy-to-intercept area equivalent radius suitable for radar networking, and serves as a method for evaluating the low-to-intercept performance of networked radars.

[0034] The technical solution of the present invention solves the technical problem that networked radar lacks a physically meaningful, quantifiable, and intuitive intercept probability performance evaluation method: the existing networked radar intercept probability evaluation method mainly includes interception factor, interception probability, and radiation power. Among them, the interception factor equates the networked radar to a single radar, ignoring the position distribution of each sub-radar. The interception probability requires prior information on the parameters and position of the known interceptor, which is not easy to obtain in practical applications. Radiated power is an indirect measure of interception performance, and it is difficult to provide quantitative and intuitive evaluation. This patent provides a physically meaningful and quantifiable performance measurement method for intuitively characterizing the interception probability performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of a method for evaluating networked radar intercept probability performance provided by an embodiment of the present invention;

[0036] Figure 2 It is a schematic diagram of an area that is easily intercepted by a networked radar provided in an embodiment of the present invention;

[0037] Figure 3 It is a structural diagram of a networked radar intercept probability performance evaluation system provided by an embodiment of the present invention;

[0038] Figure 4 is a schematic diagram of a simulation scenario provided by an embodiment of the present invention;

[0039] Figure 5 This is a simulation result diagram of the equivalent radius of the easy interception area of ​​the networked radar provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] In view of the fact that the existing networked radar intercept probability performance evaluation method lacks consideration of physical meaning and obtainable prior information, and is difficult to adapt to the performance evaluation of low interception radar when the radar is networked, the present invention proposes and adopts the equivalent radius of the easy interception area of ​​the networked radar to evaluate the low interception probability performance.

[0042] like Figure 1 As shown, an embodiment of the present invention provides a method for evaluating the intercept probability performance of a networked radar, comprising the following steps:

[0043] Step 1: Establish a networked radar system model, wherein the networked radar system includes multiple transmitting nodes. The transmitting node of the networked radar network is m, and the average transmitting power of the transmitting node m at time t is P Am,t .

[0044] Step 2: Calculate the radiated power: Calculate the radiated power of each transmitting node at each position in space using the radar equation. Assume that each transmitting node is a MIMO radar. For transmitting node m, the distance is R Im The radiated power at can be expressed as:

[0045]

[0046] Step 3: Calculate the critical signal-to-noise ratio of the interception receiver: According to the detection probability and false alarm probability of the interception machine, the critical signal-to-noise ratio of the interception signal is obtained. Ith , the detection probability of the interceptor p D and false alarm probability p F The relationship can be expressed as:

[0047]

[0048] The critical signal-to-noise ratio (SNR) of the interceptor signal can be obtained based on the detection probability and false alarm probability. Ith .

[0049] Step 4: Calculate the equivalent radius of the easy-to-intercept area: According to the radiation power and critical signal-to-noise ratio, obtain the easy-to-intercept area of ​​the networked radar, and then calculate the equivalent radius of the corresponding easy-to-intercept area. t for:

[0050]

[0051] Where Area represents the area that meets the conditions. Figure 2 A schematic diagram of the easy-to-intercept area of ​​a MIMO networked radar system is given, and the easy-to-intercept area is shown in the shaded part of the figure. I represents the noise power of the interceptor, which can be specifically expressed as:

[0052] N I =KT I F I B I (4)

[0053] K is the Boltzmann constant. T I , F I and B I are the absolute temperature, noise coefficient and bandwidth of the interceptor respectively. Then according to the easy interception area A of the networked radar t Calculate the equivalent radius of the easily intercepted area NCEVR t , which can be specifically expressed as:

[0054]

[0055] like Figure 3 As shown, the embodiment of the present invention provides a networked radar intercept probability performance evaluation system of a networked radar intercept probability performance evaluation method, including:

[0056] A networked radar system building module, used to establish a networked radar system consisting of multiple transmitting nodes;

[0057] The radiation power calculation module is used to calculate the radiation power of each transmitting node at each position in space through the radar equation;

[0058] A critical signal-to-noise ratio calculation module is used to calculate the critical signal-to-noise ratio required for the interception receiver to intercept the signal under certain detection probability and false alarm probability conditions;

[0059] The equivalent radius calculation module is used to calculate the easy-to-intercept area of ​​the networked radar according to the radiation power and the critical signal-to-noise ratio, and then calculate the equivalent radius of the corresponding easy-to-intercept area.

[0060] Example 1

[0061] (1) Establishing a networked radar system model

[0062] In this embodiment, it is assumed that there are three transmitting nodes, which are respectively recorded as node 1, node 2 and node 3. For the sake of simplicity, it is assumed that they are all located in the same horizontal plane and distributed at a certain distance. The average transmission power of each node at a certain moment is about 10 kilowatts (this value is only for example). Since the power of the three nodes is the same, their coverage radiation characteristics can be uniformly processed in subsequent analysis.

[0063] (2) Calculation of radiated power

[0064] When calculating the radiation power of a node, a simplified radar equation can be used, which mainly considers factors such as the average transmission power of the node, antenna gain, effective scattering cross section, distance, and path loss. If the path loss factor (used to characterize the power attenuation during free space or near-free space propagation) is assumed to be 2, then as the distance increases, the power radiated by the node at each point in space will decay in the manner of the square of the distance. By gridding the radiation power distribution of each node and then superimposing the radiation distribution of three nodes, the comprehensive radiation power of the system at any position can be obtained.

[0065] (3) Calculation of critical signal-to-noise ratio of intercept receiver

[0066] The critical signal-to-noise ratio of an intercept receiver is related to its ability to achieve a certain detection probability and control the false alarm probability. Assume that the detection probability is required to be 0.9 and the false alarm probability is 1 in 1 million (i.e., 1×10 -6 ), then according to conventional signal detection theory, a threshold signal-to-noise ratio can be obtained by looking up relevant tables or using signal processing software. For example, the threshold signal-to-noise ratio is about 13 decibels (converted into a linear proportional value of about 20). When the ratio of the signal to noise received by the receiver exceeds this threshold, the set detection and false alarm requirements can be met.

[0067] (4) Calculate the easily intercepted area and its equivalent radius

[0068] 1) Determine the noise power

[0069] Assuming that the receiving bandwidth of the interception receiver is 10 MHz, the absolute temperature is 290 Kelvin, and the noise coefficient is about 2, combined with the Boltzmann constant, it can be calculated that the system noise power is about 10 -14 Watt level.

[0070] 2) Determine the easy-to-intercept area

[0071] When the ratio of the system's radiation power at a certain point to the interceptor's noise power is greater than the threshold signal-to-noise ratio determined previously, the point belongs to the easy-to-intercept area. By traversing or meshing the entire surveillance plane, we can obtain the easy-to-intercept area consisting of all points that meet this condition. If the easy-to-intercept area obtained by numerical simulation is approximately 5.2×104 square meters, it can be regarded as an equivalent circle, and the equivalent radius is calculated to be approximately 128.5 meters.

[0072] 3) Interpretation of results

[0073] This equivalent radius shows that, under the combined radiation of the three nodes of the networked radar, if the interceptor is within about 128.5 meters from the center of the system or the main coverage area (only referring to the concept of equivalent circular distance), it can obtain a signal that is sufficient to exceed the threshold signal-to-noise ratio, thereby achieving interception of the radar radiation.

[0074] Example 2

[0075] (1) Establishing a networked radar system model

[0076] In the second embodiment, it is assumed that the networked radar includes 4 transmitting nodes with different transmitting powers, such as 15 kilowatts for node 1, 10 kilowatts for node 2, 8 kilowatts for node 3, and 12 kilowatts for node 4. Each node is distributed in a certain area and is also on the same horizontal plane. Due to the different power levels of the nodes, the coverage distribution of a single node is no longer consistent and needs to be calculated separately and then superimposed.

[0077] (2) Calculation of radiated power

[0078] To be closer to reality, the path loss factor can be set between 1.8 and 2.2 to characterize a more complex propagation environment. At this time, for each node, its own transmission power, antenna gain, and scattering characteristics need to be considered, and then the power attenuation in different radii or directions needs to be numerically simulated and calculated. The radiation power generated by the four nodes in space is superimposed to obtain the comprehensive radiation value of the overall networked radar system at each point.

[0079] (3) Calculation of critical signal-to-noise ratio of intercept receiver

[0080] In this embodiment, if the interceptor needs to ensure a higher detection probability, such as 0.95, the false alarm probability is set to 1×10 -7 , then a higher critical signal-to-noise ratio can be obtained by the same principle, such as about 15 decibels (the corresponding linear proportional value is about 31.6). This means that the interceptor must receive a stronger signal to meet the required detection and false alarm indicators.

[0081] (4) Calculate the easily intercepted area and its equivalent radius

[0082] 1) Determine the noise power

[0083] If the receiving bandwidth of the interceptor is increased to 20 MHz, the noise factor is still 2, and the temperature is 290 Kelvin, the noise power calculated by combining the Boltzmann constant will increase slightly compared with Example 1, about 10 -13 Watt level.

[0084] 2) Determine the easy-to-intercept area

[0085] According to the above method, the comprehensive radiation power of the networked radar system at each position is compared with the noise power and compared with a higher critical signal-to-noise ratio to obtain a new easy-to-intercept area. If the easy-to-intercept area estimated by simulation is 8.3×10 4 square meters, then further calculation shows that the equivalent radius of this area is approximately 162.6 meters.

[0086] 3) Interpretation of results

[0087] Since the number of nodes in this embodiment is larger, some nodes have higher power, and there is a certain degree of superposition gain, although the detection threshold of the interceptor is increased, it still shows a larger area that is easy to intercept overall, indicating that within a wider range, the interceptor can achieve the required signal-to-noise ratio and successfully intercept radar radiation.

[0088] In the above two embodiments, by giving the number of transmitting nodes, power level and path loss parameters, combined with the detection and false alarm requirements of the actual interceptor, the radiated power distribution of the networked radar is calculated respectively, the critical signal-to-noise ratio of the interceptor is determined, and then the easy-to-intercept area of ​​each system under different conditions is determined, and finally the easy-to-intercept area area and equivalent radius are quantitatively characterized. The method of the present invention can be flexibly applied to networked radars with various station layout modes, frequency bands and power configurations, and the confrontation performance evaluation between them and the interceptor can also be expanded and deeply analyzed in conjunction with more complex terrain environments and motion platform factors.

[0089] The present invention can be applied to the field of resource scheduling of low-intercept networked radars. The proposed networked radar intercept probability performance evaluation method can be used as an intercept probability performance parameter to optimize the objective function or constraint condition of the model, thereby realizing resource scheduling of low-intercept networked radars to improve anti-intercept performance.

[0090] In order to further reflect the positive effect of the interception probability performance evaluation method of the present invention, it can be used as an interception probability performance parameter for the optimization model. Under the constraints of detection performance, by scheduling radar resources, the equivalent radius of the easy interception area of ​​the networked radar is minimized, thereby improving the anti-interception performance of the networked radar. Figure 4Taking the scenario as an example, the networked radar performs the detection task of targets 1 to 10. The networked radar specifically includes radars 1, 2, 3, and 4. The movement trajectory is shown by the dotted line. The minimization of the equivalent radius of the easy interception area of ​​the networked radar is achieved through the proximal policy optimization algorithm (PPO) and the particle swarm algorithm (PSO). The equivalent radius at each moment is shown in Figure 5 The simulation results show that the present invention provides a physically meaningful and quantifiable performance measurement method to intuitively characterize the interception probability performance, and can be used to optimize the anti-interception performance of the networked radar, thereby improving the anti-interception performance of the networked radar, reflecting the positive effect of the resource allocation method of the present invention.

[0091] It should be noted that the embodiments of the present invention can be implemented by hardware, software, or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. It can be understood by a person of ordinary skill in the art that the above-mentioned devices and methods can be implemented using computer executable instructions and / or contained in a processor control code, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. Such code is provided on the carrier medium. The device and its modules of the present invention can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0092] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for evaluating the intercept probability performance of a networked radar, characterized in that: The following steps are involved: Step 1: Establish a networked radar system model, where the networked radar system includes multiple transmitting nodes; Step 2: Calculate the radiation power: Calculate the radiation power of each transmitting node at each position in space using the radar equation; Step 3, calculating the critical signal-to-noise ratio of the interception receiver: according to the detection probability and false alarm probability of the interception machine, the critical signal-to-noise ratio of the interception machine's intercepted signal is obtained; Step 4: Calculate the equivalent radius of the easy-to-intercept area: According to the radiation power and the critical signal-to-noise ratio, obtain the easy-to-intercept area of ​​the networked radar, and then calculate the equivalent radius of the corresponding easy-to-intercept area.

2. The networked radar intercept probability performance evaluation method according to claim 1, characterized in that: In the step 1, the transmitting node of the radar network is m, and the average transmitting power of the transmitting node m at time t is P Am,t .

3. The networked radar intercept probability performance evaluation method according to claim 1, characterized in that: In step 2, each transmitting node is a MIMO radar. For transmitting node m, the distance is R Im The radiated power at is expressed as:

4. The networked radar intercept probability performance evaluation method according to claim 1, characterized in that: The critical signal-to-noise ratio (SNR) of the intercepted signal in step 3 Ith , the detection probability of the interceptor p D and false alarm probability p F The relationship is expressed as: According to the detection probability and false alarm probability, the critical signal-to-noise ratio (SNR) of the interceptor's intercepted signal is obtained. Ith .

5. The networked radar intercept probability performance evaluation method according to claim 1, characterized in that: The easy-to-intercept area A of the networked radar at time t in step 4 t for: Where Area represents the area that meets the conditions; where N I represents the noise power of the interceptor, which is specifically expressed as: N I =KT I F I B I (4) K is the Boltzmann constant; T I , F I and B I are the absolute temperature, noise figure and bandwidth of the interceptor respectively; Then according to the easy interception area A of the networked radar t Calculate the equivalent radius of the easily intercepted area NCEVR t , specifically expressed as:

6. A networked radar intercept probability performance evaluation system according to any one of claims 1 to 5, characterized in that: include: A networked radar system building module, used to establish a networked radar system consisting of multiple transmitting nodes; The radiation power calculation module is used to calculate the radiation power of each transmitting node at each position in space through the radar equation; A critical signal-to-noise ratio calculation module is used to calculate the critical signal-to-noise ratio required for the interception receiver to intercept the signal under certain detection probability and false alarm probability conditions; The equivalent radius calculation module is used to calculate the easy-to-intercept area of ​​the networked radar according to the radiation power and the critical signal-to-noise ratio, and then calculate the equivalent radius of the corresponding easy-to-intercept area.

7. A computer device, characterized in that: The computer device includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor executes the steps of the networked radar intercept probability performance evaluation method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that: A computer program is stored, and when the computer program is executed by a processor, the processor executes the steps of the networked radar intercept probability performance evaluation method as described in any one of claims 1 to 5.

9. An information data processing terminal, characterized in that: The information data processing terminal includes the networked radar intercept probability performance evaluation system described in claim 6.

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