DirectSequence CodeDivision Multiple Access (DSCDMA)

For our purposes in this chapter, we shall assume that the receiver is perfectly capable of regenerating the transmitted codes corresponding to each of the users' transmissions, and as such we shall ignore all synchronization issues dealing with the acquisition and tracking of these codes at the receiver. The chapter is divided into two main sections, namely, single-carrier DS-CDMA and multiple-carrier DS-CDMA. Each of these sections will focus on the average bit error rate (BER) performance of the corresponding DS-CDMA system when transmitted over a generalized fading channel such as those modeled in previous chapters of this book. As before, the emphasis will be on using the alternative forms of the classic functions developed in Chapter 4 to simplify the resulting expressions. Although we shall restrict ourselves to binary DS modulation (spreading waveforms), we shall allow for the possibility of other than a rectangular pulse shape to represent the PN code chip waveform.