Abstract

In MC-CDMA system, the guard interval (GI) generally is longer than the channel impulse response to mitigate inter symbol interference (ISI). But in this environment, SNR is decreased and BER is high. So, some approaches to determine the optimal GI length under SNR and BER constraints have been proposed. In this paper, we propose the new theoretical expression that can determine optimal guard interval based on modeling the channel uniform distributed exponential decay channel, when the system parameters such as RMS delay spread and the channel parameters as the number of sub-carriers are given for MC-CDMA system.