Windowing techniques for OFDM systems [articol]

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is a technique which converts a frequency-selective fading channel into several nearly flat-fading channels and combats the intersymbol interferences (ISI) caused by multipath propagation. One of the problems of the OFDM technique is the inter-carrier interference (ICI) due to frequency offset and phase error. To reduce the ICI, pulse shaping and windowing techniques can be applied. To obtain an optimal windowing function, some ICI minimization criteria, as Lagrange, can be used or a numerical algorithm specific for adaptive filtering can be employed.