Active and Passive Radar Cooperative Target Tracking Method Assisted by Doppler Information

Incorporating Doppler information into a hybrid active-passive radar system can effectively enhance target tracking performance. However, in practical tracking scenarios, using a low pulse repetition frequency can lead to Doppler ambiguity. Ambiguous Doppler measurements not only fail to improve target tracking accuracy but also significantly degrade overall tracking performance. To utilize accurate target Doppler information, this paper proposes a tracking method with Doppler ambiguity resolution based on a Gaussian mixture probability hypothesis density (GM-PHD) filter for penetration target tracking in a hybrid active-passive radar system. This method achieves joint processing of multi-target tracking and Doppler ambiguity resolution. the method utilizes radar's position measurements for filtering to obtain an estimated value of the target's radial velocity. It then calculates potential target radial velocity values based on ambiguous Doppler measurements and selects the radial velocity value with the maximum likelihood as the Doppler measurement without ambiguity. After Doppler measurements are unambiguous, the target states are updated again. Simulation experiments demonstrate that the GM-PHD filter with Doppler ambiguity resolution can ensure radar system tracking performance.