Performance evaluation of D3LS and NCLS smart antenna in mobile communications

Abstract

A smart antenna was proposed to improve wireless communication systems. The smart antenna may comprises direction-of-arrival (DOA) estimation and/or adaptive antenna. The DOA estimation technique is used to estimate direction of transmitted signals. An adaptive antenna has ability of suppressing undesired signals namely interference or jammers in specific directions while receive only the desired one. There are a number of methods proposed to conduct in such way, including multiple signal classification (MUSIC), least mean squares (LMS), sample matrix inversion (SMI), recursive least squares (RLS), and their derivative forms as seen in the literatures in [1]. These methods require a training sequence or known information for adaptation and/or DOA estimation. Although a constant modulus algorithm (CMA) was proposed without the need of training sequence, it has a slow convergence. © 2012 IEICE.