Two Blind Adaptive Equalizers Connected in Series for Equalization Performance Improvement

Monika Pinchas

Department of Electrical and Electronic Engineering, Ariel University of Samaria, Ariel, Israel.

DOI: 10.4236/jsip.2013.41008                

Abstract

A variable step-size parameter is usually used to accelerate the convergence speed of a blind adaptive equalizer with N₁ + N₂ －1 coefficients where N₁ and N₂ are odd values. In this paper we show that improved equalization performance is achieved when using two blind adaptive equalizers connected in series where the first and second blind adaptive equalizer have N₁ and N₂ coefficients respectively compared with the case where a single blind adaptive equalizer is applied with N₁ + N₂ －1 coefficients. It should be pointed out that the same algorithm (cost function) is used for updating the filter taps for the different equalizers and that a fixed step-size parameter is used. Simulation results show that for the low signal to noise ratio (SNR) environment and for the case where the convergence speed is slow due to the channel characteristics, the new method has a faster convergence speed with a factor of approximately two while leaving the system with approximately the same or lower residual intersymbol interference (ISI).

Keywords

Blind Adaptive Equalizers; Blind Adaptive Deconvolution; Equalization Performance; Variable Step-Size

Conflicts of Interest

The authors declare no conflicts of interest.

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