CPAFC-based radar seeker velocity tracking loop design

The velocity tracking loop in a radar seeker plays a vital role in the 3D joint tracking of range, velocity and angle. In order to obtain a satisfying velocity tracking performance, this paper designs a velocity tracking loop which utilizes the cross product automatic frequency control (CPAFC) algorithm to measure the frequency difference in target´s Doppler domain, and passes the measured value into the loop filter (LF) to predict target´s velocity of the next coherent processing interval (CPI). Experiment results demonstrate that compared with the velocity tracking loop using the high-low Doppler tracking filter, the proposed method has a smaller root-mean-square error and a better tracking performance.