Mitigation of Phase Noise and Phase Rotation in Single-Carrier Communication Systems Using Pilots and Smoothing Technique

Abstract

Phase noise and phase rotation must be carefully considered when designing a communication system since an accurate prediction and removal of the phase noise can improve system performance and allow for design relaxation of the RF local oscillators to conserve power. This work proposes a method to mitigate phase noise and phase rotation in data symbols using preamble and pilots for single-carrier communication systems. It is a 3-step approach. First, the phase noise and phase rotation in received samples of preamble and pilots are estimated in the time domain. Then, the estimated phase noise and phase rotation are smoothed by using a smoothing technique, which tracks the main temporal dynamics of the phase noise and phase rotation in these received samples. Next, the smoothed results are used to interpolate for the phase noise and phase rotation of received samples in data symbols between two pilots or between preamble and a pilot in the case of the initial data symbol. The main novelty is the use of smoothing, which improves the robustness to channel noise and enables the method to exploit the temporal dynamics of phase noise and rotation in preamble and pilots to better estimate the phase noise and rotation in data symbols. Simulation results confirmed that the proposed method is able to significantly remove phase noise and phase rotation, largely outperforming a widely used interpolation method which does not employ the smoothing technique.