An E-Band FMCW Radar Receiver With Arbitrary-Path Spillover Cancellation

Abstract

This article presents an E-band receiver (RX) with spillover cancellation for frequency-modulated continuous-wave (FMCW) radars. To reject spillover from both TX-RX coupling and undesired reflections from radar assembly (such as bumper reflection), a spillover replication method based on frequency-delay translation through a single-sideband (SSB) modulator is introduced. To keep the RX performance immune from strong spillover, we propose an in-low-noise amplifier (LNA) common-mode voltage-domain canceller. It provides high isolation between the RX signal chain and cancellation path, minimizing noise figure (NF) degradation. Spillover is rejected in the input voltage domain before entering the critical LNA stage and inducing current, thereby preserving the linearity. Prototyped in 65-nm CMOS, the RX exhibits 5.7–7.2-dB NF and −11.4-dBm IP1 dB across 69–76.5-GHz range. It demonstrates that 38-dB rejection to spillover signals with offset frequency up to 3.6 MHz and power up to −10.4 dBm, while keeping the maximum NF degradation below 1–1.5 dB.