Target detection performance analysis for airborne passive bistatic radar

For a ground-based/airborne passive bistatic radar, its performance is dependent on the geometrical configuration and the passive transmit signal attributes. Theoretical power budget and ambiguity function analysis using a ground-based non-cooperative transmitter of opportunity with a passive bistatic radar being airborne but stationary (airship, etc.) had shown that target detection performance is limited by the strong direct path coupling signal. In comparison, the bistatic ground clutter power is significantly lower and even more so for noise power. For the passive radar to perform satisfactorily, sufficient attenuation must be provided for the direct path and strong ground clutter signals, corresponding to increasing the height of the target peak on the ambiguity function pedestal. In addition, performance could also be improved by increasing the time-bandwidth product (assuming no target migration issues), which lowers the pedestal of the ambiguity function of the strong direct path interfering signal.