Design and performance of OFDM-CDMA system in fading channels

In recent years orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) systems have gained considerable attention due to their use in high speed wireless communication. Both OFDM and CDMA have distinguishing features, for example, the former is almost completely immune to multipath fading effects, and the later has multi-user capability. Orthogonal frequency division multiplexing-code division multiple access (OFDM-CDMA) attempts to combine these features, so that we can achieve higher data rates for multiple users simultaneously. In this paper an OFDM-CDMA system is described and simulated. Its performance is compared with direct sequence code division multiple access (DS-CDMA) system. Simulation results presented show that overall performance of OFDM-CDMA is better than the DS-CDMA system.