Modeling and analysis of voice/data call admission control scheme in CDMA cellular network for variation in soft handoff threshold parameters

Abstract

In CDMA cellular networks the variation in soft handoff coverage area can be taken as the parameter influencing the performance of the system. In this paper, an analytical model is developed and analyzed for the concerned target cell in CDMA cellular network. The model proposed in this paper is for integrated data and voice services. It is based on reservation for handoff voice and data calls along with call queuing scheme for handoff data calls. Preemptive priority scheme is used for handoff voice calls over ongoing data calls. Upper channel limits are set for new voice as well as data calls to give priority to handoff calls. Two dimensional Markov birth-death process is used for modeling the problem. The data handoff queue capacity is considered as function of soft handoff coverage area which depends on the two soft handoff threshold parameters T_ADD and T_DROP. Variation in these threshold parameters is stated in term of variation in handoff data call queue capacity. The performance parameters of the model mainly new voice and data call blocking probabilities and handoff voice and data dropping probabilities are analyzed for variation in upper channel limit for new voice call and handoff data call queue capacity.