Modeling and analysis of the effects of PLL phase noise on FMCW radar performance

The phase noise of a phase-locked loop (PLL) has a great impact on the performance of frequency-modulated continuous-wave (FMCW) radar. To examine the effects of the phase noise on FMCW radar performance, a model of an FMCW radar with a noisy PLL is developed. A filter-based technique for modeling the PLL phase noise is described. The radar model shows that PLL in-band phase noise affects the spatial resolution of the FMCW radar, whereas PLL out-of-band phase noise limits the maximum range. Finally, we propose a set of design constraints for PLL based on the model simulation results.