Turbo Receiver Design for Phase Noise Mitigation in OFDM Systems

TL;DR

This paper introduces a turbo receiver for OFDM systems that effectively mitigates phase noise by using a variational inference-based SISO algorithm, improving overall system performance.

Contribution

The paper develops a novel turbo receiver architecture utilizing variational inference for phase noise mitigation in OFDM systems, providing near-optimal performance.

Findings

The turbo receiver significantly reduces the impact of phase noise.

The variational inference-based SISO algorithm accurately estimates phase noise.

Performance approaches that of an ideal system without phase noise.

Abstract

This paper addresses the issue of phase noise in OFDM systems. Phase noise (PHN) is a transceiver impairment resulting from the non-idealities of the local oscillator. We present a case for designing a turbo receiver for systems corrupted by phase noise by taking a closer look at the effects of the common phase error (CPE). Using an approximate probabilistic framework called variational inference (VI), we develop a soft-in soft-out (SISO) algorithm that generates posterior bit-level soft estimates while taking into account the effect of phase noise. The algorithm also provides an estimate of the phase noise sequence. Using this SISO algorithm, a turbo receiver is designed by passing soft information between the SISO detector and an outer forward error correcting (FEC) decoder that uses a soft decoding algorithm. It is shown that the turbo receiver achieves close to optimal performance.