Estimation of Phase Noise Based on In-Band and Out-of-Band Frequency Domain Pilots

We present a solid foundation for the theory and practice of using pilot tones for estimation and compensation of phase noise in a communication link. We analyze several phase estimators and illustrate their pros and cons, and we derive the necessary optimal signal-to-pilot-power relationship when the transmitted power is shared between the communication signal and the pilot tone. We show that the optimal signal-to-pilot-power ratio increases with decreasing phase noise and with increased additive noise.