Comparison of Chip Interleaved MC-CDMA and DS-CDMA with Frequency- domain Equalization

DS-CDMA with minimum mean square error frequency-domain equalization (MMSE-FDE) can provide much better performance than that with rake combining in a frequency-selective fading channel and is comparable to that of MC-CDMA with MMSEFDE. Chip interleaving is a form of channel interleaving that improves the DS-CDMA performance by converting the channel into a highly time-selective channel; the time-selectivity can be benefited with chip interleaving. When FDE is used, the frequencyselectivity of the channel is thoroughly exploited. In this paper, we apply chip interleaving to DS-CDMA with MMSE-FDE and compare its performance with chip interleaved MC-CDMA. It is found that chip interleaving improves the performance for both DSCDMA and MC-CDMA; however the performance of DS-CDMA is better than that of MC-CDMA even with chip interleaving.