Papr reduction and pilot symbol assisted channel estimation for mimoofdm and cognitive systems

Abstract

The increasing development of telecommunication raises the need newlinefor efficient usage of spectral resources so the multiplexing techniques in newlineparticular the multicarrier modulation are widely used to optimize these newlineresources Orthogonal Frequency Division Multiplexing OFDM is one of newlinethe multicarrier modulation techniques which divide the available spectrum newlineinto many carriers each one is modulated by a low data rate stream OFDM is newlineused for high data rate wireless communications because of its robustness to newlinefrequency selective fading high spectral efficiency and low computational newlinecomplexity OFDM is a modulation scheme that is especially suited for high newlinedata rate transmission in delay dispersive environm newline newline