On the Joint Estimation of Phase Noise and Time-Varying Channels for OFDM under High-Mobility Conditions

TL;DR

This paper proposes a joint estimation method for phase noise and time-varying channels in high-mobility OFDM systems, improving accuracy and reducing pilot overhead by using basis expansion models.

Contribution

It introduces a novel joint estimation approach using BEM coefficients for both phase noise and channel variation, outperforming existing methods.

Findings

Enhanced phase noise and channel estimation accuracy

Reduced pilot overhead in high-mobility scenarios

Outperforms state-of-the-art phase noise compensation methods

Abstract

The combination of the effects of Doppler frequency shifts (due to mobility) and phase noise (due to the imperfections of oscillators operating at a high carrier frequency) poses serious challenges to Orthogonal Frequency Division Multiplexing (OFDM) wireless transmissions in terms of channel estimation and phase noise tracking performance and the associated pilot overhead required for that estimation and tracking. In this paper, we use separate sets of Basis Expansion Model (BEM) coefficients for modelling the time variation over intervals of several OFDM symbols of the channel paths and the phase noise process. Based on this model, an efficient solution approximating the maximum-likelihood joint estimation of these BEM coefficients is derived and shown to outperform state-of-the-art phase noise compensation methods