Channel Assignment and Minimum Dropping Probability scheme for Handover Calls in Mobile Wireless Cellular Networks

Due to the increase of users ’ demand for wireless cellular connectivity, service provider is finding difficulty in allocation of resources for mobile nodes. In order to accommodate more number of users, the cell size in mobile wireless cellular networks is being reduced. Because of that bandwidth in each cell has become limited. Due to decrease of cell size, more number of handovers takes place. If bandwidth allocation to these handover calls is not done properly then dropping probability of handover calls will be increased. Also if sufficient bandwidth is not available to new calls, then blocking probability for newly generated calls will be increased. Dropping of handover calls is less desirable than blocking of new calls. Many schemes have been proposed to solve the problem in resource allocation. Presently available solutions are not enough to provide and maintain QOS (Quality of Service) for handover calls. In this paper we propose TDMA based dynamic channel allocation along with bandwidth window in heavy load conditions. We evaluated the performance for dropping probability for handover calls in busy traffic conditions. We applied bandwidth window, where the bandwidth window changes its size according to changing network traffic conditions. With this solution higher priority handover call (multimedia call) will get requested bandwidth, lower priority handover call (Data call) will get minimum bandwidth and probability of dropping of handover calls is reduced to minimum. More number of users will be able to get connected to network and service provider could generate more revenue