Adaptive Filtering for Full-Duplex UWA Systems with Time-Varying Self-Interference Channel

• DOI: 10.36227/techrxiv.11967813
• Publication Date: 2020-03-12T12:21:12Z
• Authors: Lu Shen; Yuriy Zakharov; Benjamin Henson; Nils Morozs; Paul Mitchell
• Keywords: Performance metric; Adaptive equalizer

<div>Abstract:</div><div><br></div><div>To enable full-duplex (FD) in underwater acoustic (UWA) systems, a high level of self-interference (SI) cancellation (SIC) is required. For digital SIC, adaptive filters are used. In time-invariant channels, the SI can be effectively cancelled by classical recursive least-square (RLS) filters, such as sliding-window RLS (SRLS) or exponential-window RLS, but their SIC performance degrades time-varying e.g., channels with moving sea surface. Their improved delaying filter inputs. This delay, however, makes mean squared error (MSE) unsuitable for measuring performance. this paper, we propose new evaluation metric, factor (SICF), which gives better indication compared to MSE. The SICF used experiments and real FD systems. A SRLS based on parabolic approximation channel variation time, named SRLS-P, also proposed. SRLS-P algorithms (with without delay) evaluated simulation lake experiments. results show that significantly improves performance, filters.</div>