Target Detection by Passive Coherent FM Based Bistatic Radar

Bistatic passive radars have many advantages over the monostatic ones because they are undetectable and silent. In passive coherent location, the original source of energy Is derived from a waveform of opportunity In the environment and the re-radiated energy from the target is processed to decide about the existence of the target. More over bistatic radars receive forward scatters from target in place of the backscatters in monostatics systems. As a result of the larger forward scattered RCS, the stealth targets can be detected easier. Passive radar does not need any frequency allocation so are very attractive for surveillance. Multipath effects and direct path Interference are two problems that should be solved. For accurate position measurement we used new ambiguity function processing and TDOA methods. This system by using terrestrial FM radio signals could detect a civil plane about 210 Km away.