Phase Noise Investigation for a Radar System with Optical Clock Distribution

This paper presents an analytical investigation of the phase noise in radar systems with optical clock distribution. In a first theoretical analysis, the phase noise of a frequency-modulated continous-wave (FMCW) optical clock signal is analyzed. In a second investigation, it is shown that the noise of the overall radar system is mainly degraded by the laser relative intensity noise and the frequency synthesizer phase noise. The theoretical analysis is validated by measurements. The measurements also show that the phase noise due to the optical components such as laser diodes, modulators, and photo detectors, is small compared to electronicially induced phase noise.