Quality of service for multimedia CDMA

This article investigates the problem of call admission control in cellular networks using code-division multiple access, which is mainly viewed as an interference management problem. Our approach is to study the effects of various system parameters and user profile characteristics on the generation of multiple access interference (MAI). Different CAC schemes are presented, and different user and system characteristics that affect the CDMA system operation are listed. The focus of our work is on the emerging third-generation wireless systems and particularly on the Universal Mobile Telecommunications System. Analytical and simulation tools were constructed for quantifying these system characteristics. The results obtained by these two models show that the outage probability for a system is very sensitive to the user bit rate and quality of service requirements. The combination of different service types has a significant effect too; even a small number of high-bit-rate users can degrade the low-bit-rate users´ performance and considerably increase their outage probability. The use of a CAC algorithm is expected to guarantee the service offered to accepted users.