Motion Parameter Estimation of LFMCW Radar Based on Secondary Mixing and 3-DPT Method

摘要

Aiming at the parameter estimation problem of high-speed moving targets with uniformly varying acceleration in LFMCW(Linear Frequency-modulated Continuous Wave) radar in the case of MTRC(migration through range cell), a method based on secondary mixing and 3-DPT(cubic discrete polynomial-phase transform) is proposed. The method utilizes the modulation symmetry of tri-LFMCW signals, firstly performing secondary mixing on the up-and-down sweeping beat signal to reduce the high-order phase dimension due to acceleration and acceleration rate. After the dimensionality reduction, the quadratic beat signal is subjected to 3-DPT processing in a slow time dimension, and the dimensionality is reduced to first-order phase, meanwhile the fast and slow time dimension coupling is eliminated, and the acceleration rate estimation is also obtained. Compensating the mixing signal by constructing the compensation function, and then the compensated signal is subjected to quadratic DPT to obtain the acceleration estimation. Finally, the compensation function is constructed again to compensate the up-and-down sweep beat signal, and the target initial distance estimation and the initial velocity are accurately estimated by decoupling processing.