Indoor imaging of targets enduring simple harmonic motion using Doppler radars

In this paper, we demonstrate the micro-Doppler signatures of rotational/vibrational targets enduring simple harmonic motions (SHM). The SHM, whether it represents vibrations or rotations, induces frequency modulations on radar returns. The returns capture certain extrinsic motion characteristics of the target which have a sinusoidal instantaneous frequency. Indoor imaging data collection experiments have been performed. The experiments have been designed, keeping in mind the presumed nature of radar returns. The experiments can be considered as precursors to the more advanced through the wall imaging applications. Cost effective Doppler radars were used high resolution time-frequency techniques, along with a new basis decomposition method and the Hough transform are applied to estimate the instantaneous frequency of the target. The results are in agreement with the ground truth