Modified Markovian decision process model for limited data rate usage algorithm

Abstract

For supporting seamless high speed mobile multimedia communications over wireless channels, vertical handover (VHO) from wireless local area network (WLAN) to cellular network (e.g., UMTS) is very important and challenging. Limited data rate usage (LDU) algorithm addresses this issue by delaying the handoff event for a certain periodthrough utilizing low data-rate channels. Thealgorithm, however, fails to supportthemobile device that returns back to the previous network after initiating VHO. The problem is more critical for the user moving to-and-fro. Addressing this limitation of LDU algorithm, this paper proposes a modified LDU scheme by redesigning the Markovian decision model. Analytical and simulation results show that the propose scheme provides better performances in terms of successful VHO, while maintaining the capacity and service blocking rate at the same level of LDU algorithm.