Intermodulation FMCW (IM-FMCW) radar for nonlinear wearable targets detection

An intermodulation frequency-modulated continuous-wave (IM-FMCW) radar for non-linear wearable target detection is proposed in this paper. The non-linearity of a wearable target is utilized to generate third-order intermodulation from the transmitted single tone and chirp signal of the radar. On the receiver chain, another chirp signal with inverted ramp is used to de-ramp the third-order intermodulation product from the non-linear target. Thus, the range of the non-linear wearable target can be obtained. Moreover, clutters from other targets without non-linearity are automatically rejected due to the absence of intermodulation products. System-level model of the proposed IM-FMCW radar was created and simulated. The simulation results prove that the proposed IM-FMCW radar has the capability to detect the range of a non-linear wearable target as well as rejecting the clutters from other linear targets.