An Enhanced Hand-Off Policy to Reduce Blocking Probability in Two-LayerWireless Systems
In this paper, we consider a two-layer hierarchy, i.e. micro and umbrella layer, cellular system, and propose a new hand-off mechanism to minimize call blocking probability of high-speed hand-off calls with reasonable performance of new and low-speed hand-off calls. We used double control for highspeed hand-off calls in micro and umbrella layer. By formulating Markov chains and using queueing analysis, we have derived call blocking probabilities for ours and those of other hand-off schemes. We have shown that our proposed policy can indeed improve blocking probabilities of high-speed hand-off calls, which leads to improved system performance. Our policy can serve as a guideline to design hand-off policies within wireless systems or inter-working policies between systems.
KeywordsBlocking Probability Guard Channel Channel Assignment Strategy Umbrella Cell Call Blocking Probability
Unable to display preview. Download preview PDF.
- L. Kleinrock. Queueing Systems Volume I: Theory. John Wiley & Sons, 1976.Google Scholar
- X. Lagrange and P. Godlewski. Teletraffic analysis of a hierarchical cellular network. In Proc. of IEEE VTC, pages 882–886, 1995.Google Scholar
- I. Panoutsopoulos, S. Kotsopoulos, K. Ioannou, and S. Louvros. Priority technique for optimising handover procedure in personal communication systems. IEEE Trans. on Vehicular Technology, 36(7):669–670, Mar. 2000.Google Scholar
- F. Quessette. Modeling and analysis of UMTS hierarchical networks. In Proc. of International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems, pages 432–437, 2000.Google Scholar
- T. S. Rappaport. Wireless Communications. Prentice Hall, 2002.Google Scholar
- F. Valois and V. Véque. QoS-oriented channel assignment strategy for hierarchical cellular networks. In Proc. of IEEE PIMRC, pages 1599–1603, 2000.Google Scholar
- J. Zander and S.-L. Kim. Radio Resource Management for Wireless Networks. Artech House, 2001.Google Scholar