Anti-unmanned aerial vehicle defense system based on synthetic aperture radar (SAR)

Abstract

The invention relates to a low-complexity and high-precision defense system for a small unmanned aerial vehicle. The system carries out 360-DEG circular trajectory scanning on airspace with an unknown height through a mechanical turntable loaded with a millimeter wave antenna, and linear frequency modulation sawtooth waves with a fixed bandwidth are transmitted. Firstly, mixing at a receiver front end is carried out to obtain beat signals; then, range direction FFT is carried out on the beat signals, and phase compensation is used for virtualizing an antenna array to a uniform linear array and through beamforming, the signal-to-noise ratio is improved; then, an improved CFAR algorithm with a unit average small selection criterion is used for signal detection, and the height angle and the distance of a target are estimated; and finally, according to the distance and the height angle, azimuth direction is carried out to obtain the image of the unmanned aerial vehicle. As for a low-altitude low-speed unmanned aerial vehicle, one position of the target can be obtained whenever the radar rotates for one circle, and the path of particle of the target is further drawn. SAR imaging and airspace signal processing algorithm are combined creatively, and uninterrupted monitoring on the airspace with an unknown height can be realized.

Description

technical field [0001] The invention relates to the field of radar signal processing, in particular to an anti-drone defense system based on synthetic aperture radar. Background technique [0002] At present, the national large-scale infrastructure, key national defense facilities, civil residences, and important corporate facilities have urgent needs for anti-drone systems for low-altitude security defense in the surrounding areas, and the requirements are getting higher and higher. Especially for small drones, which have the characteristics of low flying height and small size, it is difficult to be found when intruding, and it is also difficult to counter the invading drones, so there is a big security risk. In our country, drone "black flight" incidents have also occurred frequently. On December 28 and 29, 2013, a company in Beijing that did not have the qualifications for aerial photography and mapping, without applying for airspace, arranged for personnel to take drone...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the above existing problems, the present invention provides an anti-UAV defense system based on synthetic aperture radar. Aiming at the problems of high cost, large volume, manual operation and small defense range in the traditional anti-UAV defense system, the design A kind of UAV defense system with small size, light weight, simple structure and low loss. To achieve this purpose, the present invention provides an anti-UAV defense system based on synthetic aperture radar, comprising the following steps:

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