Three-Dimensional Micro-Doppler Parameter Estimation of Rotor Target Based on VEMW Radar

Utilizing the micro-Doppler effect caused by the rotation of rotor blades to invert parameters such as spatial position and rotational speed of targets is of great significance for the detection and identification of unmanned aerial vehicles (UAVs). The vortex electromagnetic wave (VEMW) radar can directly obtain target azimuth information. However, most existing techniques for VEMW radar are based on uniform motion models and can only extract partial parameters of the target, making it difficult to achieve precise characterization of the target. This article proposes a 3-D parameter extraction algorithm for a rotor variable speed moving target. First, the echo model of a rotor target is presented. Second, the separation of different rotor information was achieved based on the nearest neighbor criterion. At last, a set of equations containing the relationships between target structural, motion, and position parameters were established. By solving these equations, the extraction of target rotor length, wheelbase, rotational speed, acceleration, spatial position, attitude angle, and other parameters was achieved. The effectiveness and robustness of the proposed method were verified through simulation.