Dispersion Compensation for Phase-Coded FMCW Radars

Phase-coded frequency-modulated continuous-wave (PC-FMCW) radars embed a phase code (PC) into the transmitted signal, thereby representing an extension to traditional frequency-modulated continuous-wave radars. The embedded PC allows, for example, to suppress interference from other radars or to realize joint communication and radar systems. The PC is removed from the radar signal at the receiver before the received signal is processed. To this end, the receiver applies a frequency-dependent time shift.The frequency-dependent time shift, however, causes dispersion of the embedded PC and degrades the radar performance. So far, the dispersion of the PC has been neglected in the literature. In this work, we analyze the dispersion of the embedded PC and show that it is independent of the intermediate frequency of the signal. Based on this observation, we propose two novel techniques for dispersion compensation. Finally, we demonstrate the effectiveness of the proposed techniques using simulations.