Performance analysis of asynchronous multicarrier code division multiple access against direct sequence code division multiple access and long polyphase sequences for uplink powerline communication systems with impulsive noise

Abstract

In this study, the performance of two asynchronous multi-access direct sequence code division multiple access (DS-CDMA) and multicarrier code division multiple access (MC-CDMA) systems with binary and polyphase long sequences is compared. An indoor multipath powerline channel model generated from random impedance networks is used. The powerline background, narrowband and impulsive noise are modelled statistically, based on models and measurements done in previous works. A complete analytical performance study is done for asynchronous MC-CDMA employing an interval guard in the form of a cyclic prefix (CP) and periodic long sequences, which provides a better channel coding than short sequences. The analytical results are completed with Monte Carlo simulations for both, DS-CDMA and MC-CDMA systems. Under impulsive noise an upper bound in the bit error rate (BER) performance for DS-CDMA and MC-CDMA systems is obtained analytically, which is confirmed by the Monte Carlo simulations.