Performance of spread spectrum and spread time PPM in Rayleigh fading channels

摘要

The code division multiple access (CDMA) system with spread time (ST) pulse position modulation (PPM) has been proposed, which is given by the interchange between frequency and time in spread spectrum (SS) CDMA system. In this paper, we evaluate the performance of SS FSK and ST PPM in Rayleigh fading channels. The envelope detection is employed in the demodulation of both SS and S'F systems. We show symbol error probability (SEP) obtained by computer simulations to illustrate the effectiveness of SS and ST in the fading channels.