Genetic-Algorithm-Assisted Maximum-Likelihood Detection of OFDM Symbols in the Presence of Nonlinear Distortions

This letter aims at proposing the use of evolutionary computation methodologies (i.e., genetic algorithms) in order to solve the problem of the maximum-likelihood estimation of orthogonal frequency-division multiplexing symbols in the presence of nonlinear distortions. Experimental results can prove the effectiveness of the proposed detection algorithm achieved with a reasonable computational load

I. Introduction

Multicarrier modulations (MCMs) [1] are regarded as emerging technologies for new-generation networking applications. In particular, orthogonal frequency-division multiplexing (OFDM) can profit by full-digital fast Fourier transform (FFT)-based implementation and is intrinsically resilient against frequency-selective channel distortions [1]. At present, two open problems limit the efficiency of OFDM techniques when employed in real-world application testbeds: nonlinear distortions involved by power amplifiers [2] and channel-estimation errors occurring in time-varying multipath fading channels [3]. In this letter, we are focusing on the problem of the optimum OFDM symbol recovery in the presence of nonlinear distortions.