Error Performance for MC-CDMA and OFDMA in a Downlink Multi-Cell Scenario

This paper studies the error performances of two different 4G downlinks in a multi-cell environment. On the one hand, an orthogonal frequency division multiplexing (OFDM) based multiple access scheme (OFDMA), and on the other hand, a multi-carrier code division multiple access (MC-CDMA) scheme is proposed. Both transmission schemes are implemented in a cellular structure. The cellular environment model takes into account path loss and shadowing depending on the position of the mobile terminal. Further investigations are done by introducing a radio resource management (RRM) for OFDMA which can improve the performance for lower system loads. Error performances are given to compare the two multiple access proposals. The results show that MC-CDMA outperforms OFDMA in the inner part of the cell for lower resource loads by utilizing its whole diversity of used sub-carriers. At the edge of the cell, the RRM can highly enhance the OFDMA performance mainly for low resource loads and OFDMA surpasses the MCCDMA performance.