Remote Blind Motion Separation Using a Single-Tone SIMO Doppler Radar Sensor

It is a challenging task for a continuous-wave Doppler radar sensor (DRS) to linearly separate independent motions without any prior information. In this paper, a low-IF single-input multiple-output (SIMO) DRS system is designed and implemented for motion separation. The SIMO DRS system detects the signals scattered off multiple objects, and a two-step blind motion separation approach is proposed to separate motions from the DRS output. Experiments show that the SIMO DRS and the proposed motion separation approach can successfully separate combinations of triangular, sinusoidal, and random motions, as long as the velocities or initial phases of such motions are different. With the two-step approach sequentially tackling the signal separation and the nonlinear demodulation problems, both small-and large-scale independent motions can be linearly separated. These results imply the potential in practical applications of short-range tracking and localization of moving objects.