EP-based Detection for Uplink OFDM-IDMA with Carrier Frequency Offsets

Abstract

A novel detection algorithm is proposed for multiuser detection (MUD) in uplink orthogonal frequency division multiplexing-interleave division multiple access (OFDM-IDMA) systems employing the expectation propagation (EP) algorithm. Compared to the conventional elementary signal estimator (ESE) detector, the proposed detector is capable of reducing the complexity with a favorable performance imposed with the accurate estimate of the posterior distribution. Then, the proposed detector can also obtain a considerable bit error rate (BER) performance in high order modulation with high transmission rate. Finally, we design a new scheme suitable for OFDM-IDMA in the presence of multiple carrier frequency offsets (CFOs). Our simulation results illustrate that the proposed scheme can effectively mitigate the influence of multiple CFOs.