Adaptive quality of service handoff priority scheme for mobile multimedia networks

For various advantages including better utilization of radio spectrum (thro ugh frequency reuse), lower mobile transmit power requirements, and smaller and cheaper base station equipment, future wireless mobile multimedia netw orks are likely to adopt micro/picocellular architectures. A consequence of using small cell sizes is the increased rate of call handoffs as mobiles m ove between cells during the holding times of calls. In a network supportin g multimedia services, the increased rate of call handoffs not only increas es the signaling load on the network, but makes it very difficult for the n etwork to guarantee the quality of service (QoS) promised to a call at setu p or admission time, This paper describes an adaptive QoS handoff priority scheme which reduces the probability of call handoff failures in a mobile m ultimedia network with a micro/picocellular architecture. The scheme exploi ts the ability of most multimedia traffic types to adapt and trade off QoS with changes in the amount of bandwidth used, In this way, calls can trade QoS received for fewer handoff failures, The call level and packet level pe rformance of the handoff scheme are studied analytically for a homogeneous network supporting a mix of wide-band and narrow-band calls. Comparisons ar e made to the performance of the nonpriority handoff scheme and the well-kn own guard-channel handoff scheme.