volume | PIER Journals

Abstract

Receiver nonlinearity degrades signal quality in modern wireless systems. This paper proposes an adaptive post-distorter using Chebyshev polynomials as basis functions to improve numerical stability and convergence speed. Unlike conventional or distributionmatched bases, the Chebyshev basis ensures a well-conditioned input correlation matrix regardless of signal distribution. This property, together with the minimax approximation, enables the RLS algorithm to converge within a few pilot symbols - an order of magnitude faster than the power-series basis. Experiments on a real wideband receiver with OFDM and WCDMA signals show significant ACPR improvements over the power-series and Legendre bases. The proposed approach exhibits robust performance, fast convergence, and broad applicability.

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Dr. Chongchong Chen

Dr. Hongmin Lu

Dr. Fulin Wu

Dr. Yangzhen Qin