Fuzzy Logic Based Call Admission Control for Next Generation Wireless Networks

Different radio access technologies (RATs) such as UMTS, WiMax, WLAN, etc, will coexist in next generation wireless networks (NGWN). This coexistence of RATs necessitates joint radio resource management (JRRM) for efficient radio resource utilization and improved users´ satisfaction. Admitting a call into the most appropriate RAT based on many selection criteria is major challenge in NGWN. This paper focuses on joint call admission control (JCAC) algorithm which is one of the JRRM algorithms. We propose a Fuzzy Logic based JCAC scheme for NGWN. The JCAC scheme consists of local CAC algorithms and a RAT selection algorithm. Each RAT has a local CAC algorithm which select the most appropriate cell for an incoming call, and determine whether the call can be admitted into the cell or not. A RAT selection algorithm then selects the most appropriate RAT for the incoming call among the RATs whose selected cell meets the local call admission condition. The proposed JCAC scheme is illustrated using two local CAC criteria and five RAT selection criteria.