Multi-Carrier DS-CDMA using Frequency Spread Coding

Abstract

In multi-carrier direct sequence code division multiple access (MC-DS-CDMA), narrow-band DS signals are parallel transmitted in several sub-carriers and each signal suffers from flat fading. Hence, the effect of inter-chip interference can be eliminated. However, no path diversity gain can be obtained. In this paper, as a method to solve this problem, we propose to apply frequency spread coding to MC-DS-CDMA achieving explicit frequency diversity without reduction of bandwidth efficiency. The computer simulation results show its effectiveness in terms of the average bit error rate in a down-link of a single cell environment. In addition, the proposed system is also compared with a multi-carrier CDMA system applying spreading codes in frequency domain and a DS-CDMA system using RAKE revier.