Passive Bistatic Radar Detection Performance Prediction Considering Antenna Patterns and Propagation Effects

This article deals with the problem of detection performance prediction for passive bistatic radars that use illuminators of opportunity, such as radio or television transmitters. First, a simplistic free-space propagation model is introduced. Next, the effects of the transmitter and receiver antenna patterns are analyzed. Then, the influence of the pattern-propagation factor is investigated, considering the elevation patterns, multipath, and diffraction. The performance prediction of the free-space model and a more realistic model with antenna patterns and propagation effects are compared. The variation of the echo power level caused by the propagation effects predicted in the simulations is verified with real data acquired with an FM-based passive radar. The presented approach allows for a more realistic prediction of the passive radar performance to be achieved in comparison with a simple free-space propagation assumption. Some examples of passive radar performance optimization using the introduced methodology are presented.