Multidimensional signaling and per-symbol detection for high data rate DS-CDMA systems

A novel multidimensional signaling and per-symbol detection are proposed for the uplink of DS-CDMA systems to achieve a constant envelope modulation and coherent demodulation while providing variable and high data rates. Unlike the conventional precoding technique, this scheme increases the data rate by compensating a loss in the information rate incurred by the constant envelope signal. It is shown that an optimum rate of multidimensional signaling can be found for the bit SNRs of interest, and the proposed scheme with 4-parallel multicodes offers significant gain over conventional DS-CDMA