Resource Sharing in an Integrated Wireless Cellular/WLAN System

The integration of cellular networks and wireless local area networks (WLANs) aims to take advantage of the coverage-complementary characteristics of both wireless networks. For applications which require quality of service (QoS) guarantee (e.g., voice, real-time video), admission control is necessary so as to limit the number of connections in a network. A connection request will be blocked if the minimum bandwidth requirement cannot be satisfied. In this paper, we propose an integrated cellular/WLAN system with resource sharing capabilities. In this system, we analyze two admission control algorithms, namely: cutoff priority and fractional guard channel. The admission algorithms consider new connection requests, requests due to either horizontal handoff or vertical handoff. If one access network does not have enough resources to support a handoff connection request, the request will be transferred to another network. We propose an analytical model and determine the new connection blocking, handoff dropping probabilities of this integrated cellular/WLAN system. Results show that the performance improves significantly when resource sharing is allowed between different wireless access networks.