| Various technologies and cellular architectures have been proposed in attempting to achieve higher system capacity. With problems inherent in each system, there is always a trade-off between high system capacity and quality of services (QoS), such as call blocking probabilities and link quality. An effective call admission control is invoked to resolve the trade-off with a goal of maximizing capacity while ensuring QoS. In this thesis, methodical approaches to finding better call admission control schemes are developed for three major cellular networks: (1) FDMA/TDMA cellular networks, (2) hierarchical cellular networks, and (3) DS/CDMA cellular networks.;For the FDMA/TDMA cellular networks, subject to the constraints on the new call blocking probability and the hVarious technologies and cellular architectures have been proposed in attempting to achieve higher system capacity. With problems inherent in each system, there is always a trade-off between high system capacity and quality of services (QoS), such as call blocking probabilities and link quality. An effective call admission control is invoked to resolve the trade-off with a goal of maximizing capacity while ensuring QoS. In this thesis, methodical approaches to finding better call admission control schemes are developed for three major cellular networks: (1) FDMA/TDMA cellular networks, (2) hierarchical cellular networks, and (3) DS/CDMA cellular networks.;For the hierarchical cellular networks, based on a novel cluster-planning-based microcell/macrocell overlaying cellular system, in which both the micro and macro layers can share the same spectrum and a hard partition of frequency spectrum is not needed, the C/I performance under the consideration of multipath fading and shadowing is analyzed. A systematical approach is developed to find an effective call admission control scheme to maximize system capacity while keeping the required outage probability for any C/I target value in various propagation environments.;For the DS/CDMA cellular networks, considering the stochastically varying traffic load, we derive the second moment of other-cell interference mathematically and build mathematical models for different call admission control schemes. Additionally, we propose the modified Linear Programming technique to search efficiently for an effective call admission control scheme. The impact of cell size on the cell's Erlang capacity in a two-slope path loss propagation environment is also investigated. |
