CN-116859385-B - Radar ultraviolet cooperative detection method and system for extremely-low RCS target

CN116859385BCN 116859385 BCN116859385 BCN 116859385BCN-116859385-B

Abstract

The invention belongs to the technical field of radar ultraviolet cooperative detection, and discloses a radar ultraviolet cooperative detection system of an extremely-low RCS target, which consists of 1 radar, a plurality of ultraviolet detectors and a core processor, wherein the radar transmits electromagnetic wave signals to a space in an active mode, the ultraviolet detectors monitor ultraviolet radiation of the target in a passive mode, and the core processor processes detected data and realizes cooperative detection of the radar and the ultraviolet system. The invention effectively combines the advantages of the traditional radar and ultraviolet detection, can enable a detection system to effectively work in various scenes, combines multiple target characteristic information detected by the radar and the ultraviolet to perform characteristic fusion judgment, realizes effective detection of the very low RCS target, enables the corresponding ultraviolet detector to be started only when the very low RCS target is detected, can realize rapid identification and accurate detection of the very low RCS target, and reasonably removes planning the combat target through the effective identification of the very low RCS target in a multi-target combat scene, thereby greatly reducing the threat brought by the very low RCS target.

Inventors

LI JINGYING
CHEN YANG
WANG FEI

Assignees

西安邮电大学

Dates

Publication Date: 20260512
Application Date: 20230708

Claims (9)

1. The radar ultraviolet cooperative detection system of the extremely low RCS target is characterized by comprising 1 radar, a plurality of ultraviolet detectors and a core processor, wherein the radar transmits electromagnetic wave signals to a space in an active mode, the ultraviolet detectors monitor ultraviolet radiation of the target in a passive mode, and the core processor processes detected data and realizes cooperative detection of the radar and the ultraviolet system; The radar ultraviolet cooperative detection method for implementing the radar ultraviolet cooperative detection system for the extremely low RCS target comprises the following steps: Step one, an airborne radar executes a long-distance conventional detection task; Step two, when a target appears in the radar detection area, calculating a radar scattering cross section of the target, judging whether the target is an extremely low RCS target, if so, carrying out conventional target detection by the radar, and if so, executing the steps four to seven; step three, the radar calculates the distance between M non-very low RCS targets, extracts and classifies the target characteristics, compares the target characteristics with information in a database, respectively judges the types of the M targets, and executes a step seven; Step four, starting a tracking mode of N very low RCS targets by a collaborative detection system, and extracting and predicting the motion characteristics of the targets in real time, wherein the motion characteristics comprise the distance The azimuth is , ) Important information, wherein If N very low RCS targets are extracted Distance of individual targets In the time-course of which the first and second contact surfaces, The target is awakened by combining the azimuth information of the target to cover the attack An ultraviolet detector for each target, ready for ultraviolet identification, wherein The speed of light is indicated as being the speed of light, An average value of the frequency offset is represented, Representing the slope of the modulation, Indicating the azimuth angle of the beam, Representing pitch angle; Step five, in the ultraviolet identification process, the ultraviolet images detected by the ultraviolet detector are required to be processed in real time and the targets are required to be classified preliminarily; Step six, presuming the approximate size of the target of attack, combining the result of the preliminary classification in step five with the approximate size information of the target obtained in step six, and matching The extremely low RCS targets are finally classified and compared with ultraviolet information in a database, and the types of the attack targets are respectively judged; and seventhly, if the aircraft is judged, the cooperative detection system prompts an alarm, and if the aircraft is judged to be a non-aircraft, the cooperative detection system gives up tracking of the target.
2. The ultra-violet cooperative detection system for radar with very low RCS target as claimed in claim 1, wherein first, when a fighter performs a combat mission, firstly, an airborne radar performs a long-distance conventional detection mission, and the maximum detection distance can be achieved Wherein Representing the energy of the received signal and, Indicating the axial power gain of the transmitting antenna, Indicating the axial gain of the receiving antenna, The wavelength is indicated as such, Representing the radar cross-sectional area of the target, Representing the pattern propagation factor on the transmit path, Representing the pattern propagation factor on the receive path, Representing the boltzmann constant, Represents the noise temperature of the system, the unit is K, The pulse energy ratio is represented by the ratio of the pulse energy, Representing radio frequency loss, which is the product of multiple loss factors.
3. The radar ultraviolet cooperative detection system for very low RCS target according to claim 1, wherein the second step is to calculate radar cross section of the target when the target appears in the radar detection area Wherein Which represents the echo power of the object, Representing the distance of the radar from the target, Representing pulse power of radar emissions if Judging the target to be a non-extremely low RCS target, if Then the target is judged to be the extremely low RCS target, wherein Representing radio frequency loss, being the product of a plurality of loss factors, Indicating the axial power gain of the transmitting antenna, Indicating the axial gain of the receiving antenna, Representing wavelength.
4. The radar ultraviolet co-detection system for very low RCS targets of claim 1, wherein said step three, radar calculates the distance of M non-very low RCS targets Wherein , The speed of light is indicated as being the speed of light, An average value of the frequency offset is represented, Representing modulation slope, the azimuth and acceleration important motion characteristics of the target comprise azimuth angle Pitch angle Acceleration of Other features include RCS, target morphology, and target height.
5. The radar ultraviolet co-detection system of very low RCS targets of claim 1, said step five comprising: (1) Registering scenes of adjacent frames by using a method of maximum correlation; (2) Searching a region with larger distance between corresponding pixel points between two frames of images as a candidate region of a target; (3) Taking the average gray level of the inter-frame difference image as a segmented self-adaptive threshold, comparing the gray level value of each pixel with the self-adaptive threshold, if the gray level value is larger than the threshold, considering the pixel as a target, otherwise, considering the pixel as a background, and dividing the image into a target area and a background area; (4) In the inter-frame difference value image divided by the threshold, a target imaging area is compressed, and effective candidate targets are screened out by utilizing the relation between the average gray value in the candidate target area in the inter-frame difference image and the overall average gray value of the image and the shape characteristics thereof; (5) Extracting features of the screened targets, extracting corresponding feature vectors of the targets in each frame of ultraviolet image by using different feature extraction algorithms, and ensuring that the dimensions and the sizes of the feature vectors are the same, wherein the feature extraction algorithms comprise SIFT and HOG; (6) And weighting the feature vector of each frame of ultraviolet image to obtain a feature fusion vector, normalizing the feature fusion vector, and carrying out primary classification on the target by adopting an SVM algorithm.
6. The radar ultraviolet cooperative detection system for very low RCS targets according to claim 1, wherein said step six, the target imaging length in the ultraviolet image detected by the ultraviolet detector Width of the steel sheet Focal length , Combining distances in motion information of objects From the similar triangles, the approximate size of the incoming target can be inferred: , ; , ; Wherein, the Is the object of The long estimated value is used for the calculation of the value, Is the object of A wide estimate.
7. A computer device comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of a radar ultraviolet co-detection method for an extremely low RCS target applied to a radar ultraviolet co-detection system for an extremely low RCS target according to any one of claims 1 to 6.
8. A computer readable storage medium storing a computer program which, when executed by a processor, causes the processor to perform the steps of the radar ultraviolet co-detection method of very low RCS targets of the radar ultraviolet co-detection system of very low RCS targets according to any one of claims 1 to 6.
9. An information data processing terminal for implementing the radar ultraviolet cooperative detection system of an extremely low RCS target according to claim 1.

Description

Radar ultraviolet cooperative detection method and system for extremely-low RCS target Technical Field The invention belongs to the technical field of radar ultraviolet cooperative detection, and particularly relates to a radar ultraviolet cooperative detection method and system for an extremely low RCS target. Background RCS (RadarCrossSection), namely radar cross section, is a physical quantity for measuring the echo intensity generated by a target under radar wave irradiation, and is the most critical concept in radar stealth technology. It is the imaginary area of the target, expressed by the projected area of an equivalent reflector that is uniform in all directions, and has the same echo power as the defined target in the unit solid angle of the receiving direction. With the rapid development of new stealth technologies and materials for aircraft, conventional detection techniques face a number of difficulties in detecting very low RCS targets. The conventional detection means are radar detection and infrared detection. For radar detection technology, multipath interference can cause larger influence on radar signals to influence detection and tracking of targets, radar signals reflected by extremely low RCS targets are weak, effective noise reduction, enhancement, tracking and identification are required to be carried out through high-end signal processing technology, the existing signal processing system cannot effectively cope with the requirement of extremely low RCS target detection, and the design and manufacturing cost of the radar system are extremely high due to extremely high requirements on the extremely low RCS targets, so that the radar system is difficult to widely apply in certain occasions. For the infrared detection technology, the infrared radiation is greatly influenced by the ambient temperature, so that the detected background radiation is strong, and the detection effect is influenced or a false detection signal is generated due to the too low or too high ambient temperature. In addition, infrared detection is easily interfered by enemy inertial guided missiles, photoelectric interference devices and the like. It can be seen that the current conventional detection means cannot meet the requirement of efficient detection of very low RCS targets. Therefore, in order to improve the combat power and the viability of the military aircraft, the fighter is not aware of the fighter, the gatekeeper is not aware of the fighter, and the unconventional detection technology for exploring the target with extremely low RCS is urgently needed. The ultraviolet detection system working in the 'sun blind area' has extremely low ultraviolet radiation of the sky background, so that the detection background is clean, the largest natural light source is avoided, and the ultraviolet detection system works in a passive mode, thereby creating favorable stealth conditions in a specific scene. In addition, the aircraft usually has tail flame during operation, can radiate strong ultraviolet energy into space, and can well cope with conventional interference means such as electromagnetic interference, infrared interference and the like. Therefore, the advantages of the radar and the ultraviolet detection system can be effectively combined, the effective detection of the extremely low RCS target is realized, and the threat brought by the omission ratio and the extremely low RCS target is reduced. At present, aiming at extremely low RCS target detection, most detection means on the existing aircraft are radar, infrared detection and combination of the radar and the infrared detection, wherein the basic principle of radar detection is to realize target detection and positioning by utilizing interaction between electromagnetic waves and objects, radar signals are emitted to the surroundings, then received reflection signals are detected to judge information such as the position, the distance, the speed and the like of the surrounding targets, and infrared detection works in a passive mode to detect infrared energy emitted by the objects in the environment to find the targets. Through the above analysis, the problems and defects existing in the prior art are as follows: (1) When the ultra-low RCS target is detected, the multi-path interference can cause larger influence on radar signals to influence the detection and tracking of the target, the radar signals reflected by the ultra-low RCS target are weak, the high-end signal processing technology is required to be used for effective noise reduction, enhancement, tracking and identification, the existing signal processing system cannot effectively cope with the requirement of ultra-low RCS target detection, and the design and manufacturing cost of the radar system are very expensive due to the very high requirement of the ultra-low RCS target detection technology, so that the ultra-low RCS target detection system is difficult to be widely applied in certain occasio