BER performance of MC-DS-CDMA systems in the presence of timing jitter : a thesis presented in partial fulfillment of the requirements for the degree of Master of Engineering in Information and Telecommunication Engineering at Massey University, Palmerston North, New Zealand

Abstract

Multi-carrier direct-sequence code division multiple access (MC-DS-CDMA) technique, which is a combination of orthogonal frequency-division multiplexing (OFDM) and code division multiple accesses (CDMA), has been considered as an important technique for the future generation wireless systems due to its bandwidth efficiency, frequency diversity, and immunity to channel dispersion. OFDM has already been employed in many areas, such as digital audio and video broadcasting, wireless local/metropolitan area networks, and asynchronous digital subscriber lines (ADSL). Leveraging the multiple access capability of CDMA, the MC-DS-CDMA technique is an important enhancement to OFDM. Nevertheless, a major disadvantage of the MC-DS-CDMA systems is their high sensitivity to timing errors between transmitter and receiver due to the use of a large number of carriers and the superposition of signals of multiple users. In this thesis, we study the bit error rate (BER) performance of MC-DS-CDMA system under the effects of timing jitter in additive white Gaussian noise (AWGN) channel and multi-path Rayleigh fading channel, respectively. In particular, we have derived the analytical BER expressions for the MC-DS-CDMA signals in presence of white or colored timing jitters and verified the results via computer simulations.