The Study Of Adaptive Cancellation Algorithm Of The Passive Radar

Passive radar doesn't emit energy itself,but receives the reflected target of noncooperative emitter.By making use of the electromagnetic signals of radio,communication base stations,TV stations,global system(GPS),digital audio broadcasting etc.,it can detect and locate the moving targets.The main research content of this paper includes the following aspects: 1)set up the model of wave channel and the direct wave signal in the passive radar system and based on this model elaborate the principle of adaptive cancellation,propose a method to eliminate interference waves;2)select the analog television signal as a radiation source,understand the working principle of passive radar systems based on analog TV signals,analyze the influences caused by the direct wave and the multipath interference;3)give the inhibition method based on adaptive filtering algorithms LMS and NLMS for the direct wave and the multipath interference of external radiation source: by update the weight of adaptive filter constantly,eliminate the direct wave signal from the main antenna signal gradually.Finally use MATLAB simulation analysis,verified the feasibility and effectiveness of the algorithm,improved the cancellation performance of the system.