Mitigation of RF Impairments of a 160-GHz MMIC FMCW Radar Using Model-Based Estimation

Employing frequency bands above 100 GHz for future frequency-modulated continuous-wave (FMCW) radar applications necessitate hardware realizations as monolithic microwave integrated circuit (MMIC). Spurious signals stemming from hardware impairments deteriorate target detection performance, but hardware-based mitigation is not preferred, given the increased cost and size of the integrated circuits. Instead, signal processing-based mitigation is favored. In this article, an approach is proposed to mitigate hardware impairments by parametric, model-based signal processing. For one particular FMCW radar operating at 160 GHz, a behavioral model of the radar device is developed, which accounts for the hardware impairments. This device model is incorporated in the data model of a maximum-likelihood parameter estimator that both resolves target ranges and mitigates spurious signal components. The mitigation performance and the improved robustness of target detection of this approach in the presence of hardware impairments are demonstrated by measurements.