A hierarchical approach to joint call admission control in heterogeneous wireless networks

Abstract

The heterogeneous nature of the next generation wireless systems (NGWS) poses many challenges to the call admission control algorithm. In this paper, a hierarchical approach to joint call admission control is proposed for the heterogeneous wireless networks. In the proposed scheme, the joint call admission control algorithm will be divided into two; namely, horizontal call admission control (HCAC) and vertical call admission control (VCAC). This approach will avoid unnecessary signalling and processing for certain stages of the joint call admission control that are specific to an access network technology. We modify the dual threshold bandwidth reservation scheme (DTBR) to triple threshold bandwidth reservation scheme (TTBR) to support vertical handoff calls. The strong feature of this scheme is that it is based on complete sharing (CS) of the overall bandwidth, which is believed to yield high radio resource utilization while meeting guaranteed quality of service (QoS).