In this paper we study the capacity of wireless cellular network, inparticular the uplink of WCDMA system by using the two dimensional continuous-time Markov chain (CTMC) technique. Considering two types of calls: real-time (RT) calls that characterized by a quasifixed transmission rate, and best-effort (BE) calls which do notrequire strict demand but need some reliability conditions. Wedevelop an approach based on the spectral analysis for evaluatingthe cell capacity. We explicitly obtain the simultaneousdistribution of the number of RT connections and the number of BEconnections in the steady-state. This analysis allows us to simplifythe computation of the performance measures including expected delayand throughput of BE traffic. These performances are obtainedexplicitly in both cases (finite and infinite) of BE calls asfunction of system parameters like arrival rate of BE and RT calls,service rate of BE and RT calls. These results allow the operator toevaluate the cell capacity by varying these parameters independentlyof the number of BE calls according to its policy to manage thenetwork. Note that this analysis can be applied to various systemssuch as WiMAX/HSPA, and for both uplink and downlink scenarios, soour spectral analysis approach is not only applicable to the uplinkof WCDMA system. We further propose some CAC (Call admissioncontrol) policies for BE traffic. We finally conclude this work bysome numerical and simulation results. The simulation resultsobtained by the network simulator (NS2) are closely to the numericalresults of our analytical results which validate our theoreticalmodel.
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