A Study on Data Spread OFDM using Transmit Diversity

Abstract

In OFDM transmission, it is difficult to improve preformance by equalization it influence of multipath is severe become of frequency dips. A data spread OFDM scheme is effective for this degradative. However, characteristics data spreading scheme in Rayleigh fading is not always good. Because its influence is distributed to all carriers. In this paper, characteristics of Alamouti scheme (two-branch transmit diversity) in Rayleigh fading is analyzed. In order to eliminate influence of frequency dips and improve system performance. Moreover, by combining data spread OFDM with transmit diversity better performance of frequency dips and improve system performance is confirmed.