Implementation of call admission control technique in HAP for enhanced QoS in wireless network deployment

Exponential growth in the number of subscribers of mobile communication services has prompted service providers to maintain high level of quality of service (QoS). QoS performance is usually measured in terms of the probability of call blocking and probability of call dropping parameters. Recently, high altitude platform (HAP) is being explored to deploy mobile communication services due to various advantages. In this paper, a modified call admission control (CAC) technique has been proposed. We propose a novel CAC technique which uses two schemes viz. "bandwidth reservation" and "degradation scheme" to deliver the desired QoS. Under the 'bandwidth reservation scheme', we allocated dedicated bandwidth to each category of service. Consequently, when a new call request arrives and when there are no more channels available, in that particular class; we use the 'adaptive degradation scheme' under which the allocated bandwidth of each channel is reduced slightly and additional channels are created and hence allocated to the new call request. Using these schemes in conjunction with CAC, better bandwidth utilization has been obtained over preferred category of committed QoS and the connections services enjoy more available bandwidth with improve in the blocking probability and dropping probability.