Experiments on Through-the-Wall Motion Detection and Ranging

In this paper, we consider moving target detection and ranging for indoor sensing applications in urban environments. A simple method is used to determine the unambiguous range of an indoor moving target using dual frequency continuous wave (CW) radars. The dual-frequency radar employs two different carrier frequencies and simultaneously measures the phase change with respect to time, for each of the two frequencies. It uses phase comparison of the radar returns at the two frequencies to provide an estimate of the target range. The dual-frequency approach offers the benefit of reduced complexity, fast computation time, real time target tracking, and localization in highly cluttered indoor scenes. We present experimental results showing the effectiveness of the proposed method for indoor range estimation. Targets undergoing different motions, such as constant Doppler, micro-Doppler and accelerating/decelerating translation profiles are considered. The Doppler and the micro-Doppler signatures of the moving targets are also provided for each experiment, which demonstrate the utility of such signatures for indoor target classification.