Next-generation wireless networks are expected to support a wide variety of data services. In interactive data applications such as Web browsing, the time elapsed between a service request and the completion of the service is one of important QoS (Quality of Service) metrics. In wireless networks, the actual data transmission rate for a mobile terminal varies according to its wireless channel condition, and its service quality depends on the number of mobile terminals that share wireless channels of the same cell. Therefore, while predicting the values of QoS metrics such as the response time of interactive service, we need to take into account the aforementioned characteristics of wireless networks. Since mobile users want to be served without call dropping, we also need call admission control (CAC) that keeps call dropping probability below a target threshold.
In this thesis, we analyze the user-perceived performance in wireless networks and propose a call admission control scheme to keep call dropping probability below a given threshold in non-uniform traffic load. The thesis is composed of two topics. Firstly, the user-perceived performance of interactive data applications in a shared wireless packet access network is analyzed. For interactive data users with different channel conditions, elaborate analytical results for the mean page delay, the Equivalent Circuit Rate (ECR), and the system saturation point are given. ECR for a user in a shared access network is the channel rate that a dedicated connection would need in order to offer an equivalent user experience. The system saturation point is the maximum number of users that can be served without incurring a service delay longer than a given tolerance limit in a shared packet access system. These analytical results provide useful metrics in the performance prediction of a real wireless environment with multiple user groups that are served with different service rates due to multiple channel conditions. T...