Design and performance analysis of MU OFDMA Based DCSK modulation

Abstract

This paper, presents a new Multi-user non-coherent spread-spectrum system that joins Orthogonal Frequency Division Multiple Access (OFDMA) based DCSK (MU OFDMA -DCSK) modulation over AWGN and multipath fading channels.  In this scheme, the total number of subcarriers is divided among all users to send their references and information bits so as to reduce the multi-user interference (MUI). The BER performance is evaluated over multipath Rayleigh fading and AWGN channels, in the existence of multi-user interference and the analytical bit error rate (BER) equations are derived. We also study the capacity of the proposed system and compare it with that of the multi user OFDM based DCSK system. The accuracy of our study is affirmed by Simulation results which show the advantages of this approach.