On Low-Pass Phase Noise Mitigation in OFDM System for mmWave Communications

A phase noise (PN) mitigation scheme was proposed for orthogonal frequency division multiplexing (OFDM) in a previous work. The proposed scheme does not require detailed knowledge of PN statistics and can effectively compensate the PN with sufficient number of unknowns. In this paper, we analyze the performance of PN estimation/mitigation using the proposed scheme. It is shown that increasing the number of unknowns reduces the modeling error, yet increases the additive noise. Hence, increasing the number of unknowns increases the computational complexity and can even degrade the estimation performance. It is also shown that the PN spectral shape of the phase-locked-loop (PLL) based oscillator also affects the PN mitigation and that a larger PN may not necessarily degrade the performance of the OFDM system with PN mitigation. Simulations with realistic millimeter-wave (mmWave) PN and channel models are conducted to verify these findings.