The Influence of Transmitter Phase Noise on FMCW Radar Performance

It is generally agreed that the main challenges in designing a frequency modulated continuous wave (FMCW) radar are; (i) frequency sweep linearisation and (ii) controlling leakage of transmitter phase noise into the receiver. This paper addresses the latter and focuses on the seldom mentioned and often neglected problem of reflected noise from large, distant targets causing an increase in the receiver noise floor. Work has been presented since the early 1960s on techniques for reducing the effect of transmitter phase noise leakage desensitising the radar receiver of CW and FMCW radars (O´hara, 1963),(Beasly, 1990). All of this work has concentrated on the problems of direct, short path length leakage around the transmit/receive antenna