Passive Radar for Low Doppler Targets Detection using Background Estimation and Subtraction

Passive radar (PR) systems are a form of radar which uses existing transmitters in the environment for target detection and tracking. In PR systems, the receivers can receive the signal directly from the transmitter, stationary objects in the environment as well as moving objects or targets. As radar systems perform detection in both the range and Doppler simultaneously, there is usually a natural separation between the targets, which are moving, and the clutter, which involves stationary objects. However, when the target is slow-moving or when the target switches between moving towards to away from the receiver, this separation disappears. This paper presents a new method to suppress the static clutter which enhances target detection for zero Doppler targets. The algorithm is verified experimentally using a PR system built using software-defined radio and terrestrial digital video broadcast (DVB- T) signals present in the environment. The effectiveness is demonstrated using a set of well-defined metrics.