Phase noise estimation in FMCW radar transceivers using an artificial on-chip target

Estimation of phase noise (PN) has become economically feasible for use within integrated circuits. Several concepts have been proposed that obtain an estimate with high accuracy. However, these concepts require a continuous wave input signal during measurement. In this work we aim to estimate the PN power spectrum of a frequency modulated continuous wave (FMCW) radar transceiver simultaneously with its normal operation. The novel method obtains the PN power spectrum across the whole FMCW chirp bandwidth. It utilizes an artificial on-chip target (OCT), which is to be incorporated into an existing monolithic microwave integrated circuit (MMIC). Two concepts to obtain the PN power spectrum are presented and validated with measurements that deliver accurate estimates within the frequency range of interest.