A 56-66GHz FMCW radar transceiver achieves 17% fractional RF bandwidth with a dynamic tuning technique on matching networks that tracks the frequency chirp. A novel frequency tripler architecture is proposed that uses harmonic combination to enhance efficiency and output power. The transmitter (TX) output power of 8.1dBm and the receiver (RX) NF of 12.8dB support a detection range up to 15m with a 20MHz IF bandwidth. Continuous power consumption is only 62mW, which can be heavily duty-cycled thanks to a 1µs start-up time.