A fully-integrated 76-81GHz FMCW transceiver in 65-CMOS is presented for automotive radar applications. The transceiver consists of 3-transmiter, 4-receiver, FMCW synthesizer and ADC with decimation filters. The transmitter, with a TX chain including a push-push doubler, a 3-stage power amplifier employing neutralization technique and 2 power-combined topologies, shows an output power of 15dBm. The receiver, with an LNA employing a 3-stage neutralized common source (CS) with inductive degeneration, achieves a noise figure of 15dB, an input P-1dB of −20dBm, and an ENOB of 10.2-b for ADC. The double tuning modulated PLL provides FMCW waveform with −81dBc/Hz phase noise at 1MHz offset and chirp rate of 50MHz/us. The power consumption of the entire transceiver is 1.06W.