Abstract:

An accurate estimation of the phase difference change rate from received signals is a key technology in the passive locating and tracking system of single observer based on particle kinematics theory. Aiming at radar  pulse signals, a model of phase difference is established, the feature of the phase difference change rate is discussed, a new digital measurement method for measuring phase difference change rates is proposed, receiving signals are sampled directly from multiple-elements and the phase difference change rate is estimated by using digital signal processing method.  The phase difference change rate measure problem is translated into frequency measure problem by discrete Fourier transform and complex number multiply operation. The parameter estimation precision is improved by using multi-pulses information. The weighted least square estimation of the phase difference change rate is obtained from unwrapped phase. The simulation results show that this method has low signal-to-noise ratio threshold, and the precision of the phase difference change rate approaches the Cramer-Rao lower bound.