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In this paper, we investigate the call blocking probability calculations in the uplink of W-CDMA mobile cellular networks. In these networks, we distinguish two types of blocking, the new-call blocking, which concerns the initial call establishment request, and the handoff-call blocking, due to the users' mobility from one cell to the other. To analyze the system, we describe it by a Discrete Time Markov Chain, and based on it, we derive a recursive formula for the calculation of the state probabilities. Consequently, the new-call blocking probabilities and the handoff-call blocking probabilities are determined. To evaluate the proposed formulas, the analytical results are compared with simulation results. This comparison shows that the accuracy of the proposed formulas is very satisfactory.

We present a new model, named Wireless FiniteConnection-Dependent Threshold Model, for the call-level analysis of W-CDMA networks that support both elastic and stream traffic. Calls generated by service-classes of finite source population (quasi-random call arrival process) compete for their acceptance to a W-CDMA cell, under the complete sharing policy. An arriving call can be accepted with one of several contingency Quality-of-Service (QoS) requirements, depending on the resource availability in the cell; the latter is indicated by thresholds. We present an approximate but recurrent formula for the efficient calculation of the system state probabilities; consequently, the call blocking (time congestion) probabilities and other performance metrics in the uplink direction are provided. The model's accuracy is verified by simulation and found to be quite satisfactory. Moreover, the proposed model performs much better than the corresponding model of infinite number of sources.

We propose a new multirate teletraffic loss model for the calculation of time and call congestion probabilities in CDMA-based networks that accommodate calls of different serviceclasses whose arrival follows a batched Poisson process. The latter is more "peaked" and "bursty" than the ordinary Poisson process. The acceptance of calls in the system is based on the partial batch blocking discipline. This policy accepts a part of the batch (one or more calls) and discards the rest if the available resources are not enough to accept the whole batch. The proposed model takes into account the multiple access interference, the notion of local (soft) blocking, user's activity and the interference cancellation. Although the analysis of the model does not lead to a product form solution of the steady state probabilities, we show that the calculation of the call-level performance metrics, time and call congestion probabilities, can be based on approximate but recursive formulas. The accuracy of the proposed formulas are verified through simulation and found to be quite satisfactory.

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