Conventional call admission control (CAC) methods generally accept (or reject) new call arrivals on the basis of measured information such as the signal-to-interference ratio (SIR) or the total received power in the individual cells. However, this paper proposes a novel approach which combines the CAC and power control mechanisms and operates in a centralized control manner. The essence of the proposed centralized call admission control (CCAC) scheme is to combine the two mechanisms and to treat the call admission decision as an eigen-decomposition problem. In the proposed approach, a new call is accepted only if the quality-of-service (QoS) requirements of all the active links in the network can still be maintained. In order to reduce the computational complexity of the eigen-decomposition problem, the paper proposes an additional scheme which uses a norm operation rather than direct computation. The simulation results indicate that the proposed scheme, even with the norm approximation, outperforms conventional call admission methods both in terms of its blocking rate and its outage rate.
International Journal of Applied Science and Engineering 5(1): 65-74