Performance of differential multiphase parallel combinatory spread spectrum communication systems

This paper presents the performance of differential multiphase parallel combinatory spread spectrum (DMPC/SS) communication systems. In the PC/SS system, multiple pseudo-noise (PN) sequences are simultaneously transmitted out of a pre-assigned spreading sequence set. In the proposed systems, q-ary DPSK is applied to the states of each simultaneously transmitting PN sequences. The symbol error rate and average bit error rate are calculated to evaluate the performance of the proposed PC/SS systems. It is found that the 4-ary DMPC/SS system gives a superior performance compared with the conventional DPC/SS system if the number of assigned PN sequence and information bit rate are constant