A Symbol-Level FDE and Spread-Spectrum Mode Design for Multi-Code Multiple Access Systems

Design of equalizers and spread-spectrum modes or code allocation schemes is crucial for achieving good performance multi-code multiple access systems. In this paper, a symbol- level frequency domain equalizer and spread-spectrum mode are jointly designed to maximize the diversity gain with low complexity. Since the proposed transceiver scheme is independent of the orthogonal codes, it can be applied to direct sequence code division multiple access (DS-CDMA), multi-carrier CDMA (MC-CDMA) and orthogonal frequency division multiple access (OFDMA) systems. Simulation results are provided which validate the theoretical analysis.