Allocation of DS-CDMA parameters to achieve multiple rates and qualities of service

We consider a packet data DS-CDMA network which supports multiple traffic classes. Each traffic class has a different requirement on information rate and performance. Given sufficient bandwidth, these requirements can be satisfied by an appropriate assignment of power and processing gain to the users in each class. For a single class of data users we examine the relationship between delay and processing gain. We show that lowering the processing gain below a threshold can produce multiple operating points, which correspond to different delays. Two classes of traffic are then considered corresponding to voice and data, and the delay of the data users is examined as a function of powers and processing gains assigned to both classes.