Multistage Target Detector Based on M-ary Hypothesis Testing Approach in Multi-Channel Passive Bistatic Radars to Improve Target Range Resolution

: In this paper, in order to improve target range resolution, target detection problem in FM-based passive bistatic radar (PBR) is modeled as an M-ary hypothesis testing problem. To do so, we exploit some adjacent channels being transmitted from a same FM transmitter and solve the detection problem based on generalized likelihood ratio test (GLRT) framework. Due to the masking effect of strong targets as well as the time-variant nature of FM radio signal, we implement the proposed detector in a multistage manner. Indeed, in our proposed detector, targets are detected sequentially and the previously detected targets are treated as interferences to be removed yielding the detection of the weakest ones. Extensive simulation results are provided to demonstrate the capability of the proposed detection algorithm. Our simulation results show that the proposed multi-channel detector not only improves the target range resolution but also results in detection performance improvement offered by combination gain equal to the number of active channels.