Real-time tracking of bullet trajectory based on chirp transform in a multi-sensor multi-frequency radar

Radar-based tracking technologies enable sub-time-of-flight bullet detection and trajectory tracking before the bullet reaches its target and thus lead to effective reduction of injuries and casualties. The capability of robust detection, tracking, and trajectory prediction in a weak signal environment directly translates to the awareness time for force protection. In this paper, we develop a multi-sensor multi-frequency radar platform and proposed the use of piecewise chirp transform for effective signal enhancement when the Doppler signatures are highly time-varying. Performed upon the time-frequency representations with improved phase information, multi-sensor multi-frequency radars uniquely localize and track bullets through unambiguous range and direction-of-arrival estimations.