Wireless Systems A robust interference cancellation technique for DS-UWB systems using fuzzy step size LMS algorithm

This paper discusses a direct-sequence ultra-wideband (DS-UWB) system that uses the least mean square (LMS) adaptive filter for interference cancellation. Compared to the conventional LMS (C-LMS) algorithm, the fuzzy step size LMS (FSS-LMS) algorithm which we propose can perform rapid convergence with a low steady-state fluctuation error. The sequential partial update scheme is used in the proposed FSS-LMS algorithm to reduce the system complexity without trading off the bit error rate (BER). Simulations are conducted to evaluate the convergence and tracking behaviour of the proposed LMS algorithm. The BER of the DS-UWB system in a realistic UWB channel is also investigated. Copyright © 2007 John Wiley & Sons, Ltd.

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