A 77 GHz Frequency Doubling Two-Path Phased-Array FMCW Transceiver for Automotive Radar

A fully-integrated 77 GHz frequency doubling two-path phased-array frequency-modulated continuous-wave (FMCW) transceiver for automotive radar applications is proposed. By utilizing the frequency doubling scheme, the chirp bandwidth is improved, and the complexity of the frequency synthesizer and the insertion loss of the local-oscillating (LO) distribution network are both reduced. Top-injected coupled resonator based wide locking range technique is proposed in the frequency doublers to minimize the required injection power to cover the chirp bandwidth plus enough PVT variation margin, and therefore reduce the power consumption of the LO distribution network. Current-reused coupled resonator technique is utilized to implement the LO phase shifting in each receiving path. The digitally controlled artificial dielectric-based transmission lines are inserted in the low noise amplifiers to provide the operation frequency calibration capability. The receiving two-path signals are converted into intermediate frequency by low flicker noise current-mode passive mixers and then combined in the trans-impedance amplifier, followed by the reconfigurable analog baseband processing. Fabricated in 65 nm CMOS, the FMCW transceiver has achieved 1.93 GHz maximum chirp bandwidth, 12.9 ~ 13.2 dBm maximum transmitting power, and 47.8 ~ 100.7 dB programmable receiving conversion gain. The transceiver consumes 343 mW power and 4.64 mm
²
chip area including all of the pads.