Self-Interference Cancellation for Full-Duplex Massive MIMO OFDM with Single RF Chain

TL;DR

This paper presents a novel digital self-interference cancellation method for full-duplex massive MIMO OFDM systems with a single RF chain, effectively compensating phase noise and improving SI cancellation performance.

Contribution

A weighted linear SI channel estimator is proposed to mitigate phase noise effects, outperforming conventional LS estimators in SI cancellation.

Findings

Proposed estimator reduces residual SI power significantly.

Method outperforms LS estimator in strong SI scenarios.

Effective for systems with low oscillator quality.

Abstract

In this paper, the digital self-interference (SI) cancellation in a single radio frequency (RF) chain massive multi-input multi-output (MIMO) full-duplex (FD) orthogonal frequency division multiplexing (OFDM) system with phase noise is studied. To compensate the phase noise, which introduces SI channel estimation error and thus degrades the SI cancellation performance, a weighted linear SI channel estimator is derived to minimize the residual SI power in each OFDM symbol. The digital SI cancellation ability of the proposed method, which is defined as the ratio of the SI power before and after the SI cancellation, is analyzed. Simulation results show that the proposed optimal linear SI channel estimator significantly outperforms the conventional least square (LS) estimator in terms of the SI cancellation ability for the cases with strong SI and low oscillator quality.