Optimizing medium access control for rapid handoffs in pseudocellular networks

The steadily decreasing cost of wireless local area network (WLAN) technology motivates the concept of pseudocellular networks that support real-time traffic and seamless mobility with WLAN-type infrastructure, in addition to the standard low-mobility data applications of WLAN. A key challenge in such networks is the support of highly mobile users with real-time traffic, because of the high handoff rate resulting from small cell sizes. In this paper, we show that timely mobile-centric handoffs can be achieved using optimized ALOHA-like reservation schemes which, for a given call drop probability, require significantly fewer reservation resources than conventional methods. For Poisson handoff traffic, we employ dynamic programming to derive an optimal stationary policy. We then use these results as a building block for obtaining adaptive reservation schemes (dynamically varying the number of minislots per frame) for bursty handoff traffic.