Blocking Probability Of Handoff Calls Research Articles

A Novel Dynamic Guard Channel Scheme For Channel Allocation In Cellular Mobile Networks

In future, cellular mobile networks will employ micro cells and pico cells to support higher capacity [1], thus increasing the frequency of call handoffs and dramatizing the effects of non-stationary traffic conditions due to fluctuations in new call arrivals and mobility patterns, and the achieved handoff call-blocking probability may deviate significantly from the targeted objective. To minimize subscriber dissatisfaction, the requirement of keeping the handoff call-blocking probability at a targeted objective in the mobile networks under non-stationary loading condition becomes even more important. So, an efficient call-handling scheme in a base station for reducing the blocking probability of prioritized calls is needed in cellular mobile networks.

Optimal prioritized channel allocation in cellular mobile systems

Under the cutoff priority discipline, the optimal prioritized channel allocation problem is formulated, which minimizes the weighted average blocking probability of handoff calls while ensuring the prespecified grade of service for new calls and the co-channel interference constraints. We use the concept of pattern to deal with the problem more conveniently. Using Lagrangean relaxation and subgradient optimization techniques, we obtain high-quality solutions with information about their deviations from true optimal solutions. Computational experiments show that our method works very well. Scope and Purpose Channel allocation is one of the most important problems in the design of cellular mobile systems. Since the number of cells of forthcoming networks will increase rapidly, this problem will be of even greater importance in the future. In cellular mobile systems, a new channel should be assigned by the new base when a call enters an adjacent cell. It provides continuation of ongoing calls as the user travels across cell boundaries, and is called handoff. The handoff call is forced to terminate before completion if there are no channels available in the new cell. However, in many practical situations, the blocking of a handoff call attempt is critical since it will result in a disconnection of the call in the middle of conversation. Thus, for reducing the blocking probability of handoff calls, several algorithms based on the cutoff priority scheme have been introduced in the literature. In the cutoff priority scheme, priority is given to handoff calls by exclusively reserving some channels called guard channels for them. In this article, we formulate a prioritized channel allocation problem under the cutoff priority scheme in general multicell environments, and suggest an efficient algorithm to solve that problem.