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Handover in digital cellular mobile communication systems A mathematical formulation is developed for systematic tracking of the random movement of a mobile station in a cellular envkonment. It incorporates mobility parameters under generalized conditions, so that the model could be tailored to be applicable in most cellular environments. This model is then used to characte.lce different mobility-related traffic parameters in a cellular system. These include the cell residence time of both new and handover calls, channel holding time and the average number of handovers per call. It is shown that the cell residence time can be described by the generalized gamma distribution, while the channel holding time can be best approximated by the negative exponential distribution. Based on these findings a teletraffic model that takes the user mobility into account is presented and is substantiated using a computer simulation. Further, the influence of cell size on new and handover call blocking probabilities is examined. The effect of the handove