Weak Signals Extraction and Imaging Analysis in Bistatic ISAR Systems Based on Stochastic Resonance
Hongwei Li · Dianzi xuebao · 2012
In the bistatic ISAR systems,in order to solve the problems of weak scatters detection and identification in strong noise background,the stochastic resonance(SR) was applied to extract the information of weak scatters.On the assumption that the strong scatters could be detected,the signals after de-chirp were disposed through transformation in fast time axis firstly,which made the signals satisfy the condition of adiabatic approximation;then the SR was used to detect the signal frequency that expressed the instantaneous range difference;after that,some processing were implemented to confirm the right positions of weak scatters and to improve the output signal-noise-ratio(SNR).Numerical simulations shows that the SR can improve the SNR largely and enlarge the dynamic bound of radar receiver.