Quality of service based access control schemes for wireless packet CDMA

This dissertation concentrates on the design and modeling of packet access schemes for multimedia wireless cellular networks based on code division multiple access (CDMA) technique. We decompose the problem of development of a differentiated quality of service (QoS) based access mechanism into two parts, corresponding to forward and reverse links. A dynamic packet access mechanism is proposed for the reverse link to provide statistical multiplexing among users with different QoS requirements. System performance and flexibility are improved by using special characteristics offered by the CDMA technique. An analytical method has been presented to determine users' power and maximum available bit rate in a heterogeneous traffic environment. A Markovian approach is used to model the system behavior. The performance is evaluated and design parameters are optimized considering packet dropping by excessive delay and packet corruption due to interference considering both voice and data traffic in a multi-cell environment. We provide all the possible system performance measures to characterize the developed access mechanism.; In the reverse link, resource allocation and scheduling mechanisms are developed using diversity areas as a new dimension of flexibility for packet transmission. We propose the multilink architecture and analyze the system performance in terms of packet delay and probability of loss. We present the modeling of the multiple link system based on the Markov Modulated Poisson Process (MMPP) and show how a simplified approximate model based on a much smaller number of MMPP states can capture the system performance. Simulation is also performed for comparison of analytical model as well as evaluation of the system behavior under circumstances in which system analysis is very complicated and not practically tractable. A dynamic load balancing technique is developed to further improve the system performance. We propose two scheduling algorithms for the transmission of packets in the diversity area and compare their performances. Finally, we present a hierarchical architecture to provide services to wireless mobile terminals using label switched packet transfer.