| It is anticipated that wireless multimedia services will find widespread acceptance over the next decade. The objectives that shaped current second-generation wireless networks have been expanded in third-generation wireless information networks to provide truly ubiquitous access and integrated multimedia services [88].; However, to make the vision of ubiquitous wireless multimedia communications a reality, many technical problems remain to be solved. The combination of bit-rate variability of compressed video traffic and inferior quality of a wireless fading channel causes low bandwidth efficiency, high data-error rate, and long delay to wireless multimedia applications.; This research tries to provide solutions to those problems. Guided by the end-to-end quality-of-service (QoS) management fundamental principles, following two issues are studied: (1) bit-rate variability and bandwidth requirement reductions at an application layer and (2) QoS concerned error control at a data-link layer.; The former alleviates resource consumption pressure from the lower network layer; the later conceals adverse properties of a wireless channel from the upper network layer. As the result, the QoS constrained wireless multimedia applications are possible.; In the first part of the dissertation, we address the problem of how to represent a video stream in a way that can reduce network resource requirement without sacrificing the video stream's quality. An original buffer-less scene-based traffic-shaping algorithm and a QoS concerned traffic-shaping algorithm are contributed. The performances and potential applications of these algorithms are evaluated.; In the second part of the dissertation, we address the problem of how to transmit a video stream at a data-link layer with QoS constrains. A novel QoS aware error control scheme (QSR-ARQ) and its improved version, hybrid QSR-ARQ (HQSR-ARQ), are proposed. The design philosophy, the computer simulation configuration, the performance analysis, and the compute simulation results are presented. |
