Performability Modelling of Handoff in Wireless Cellular Networks and the Exact Solution of System Models with Service Rates Dependent on Numbers of Originating and Handoff Calls

Mobility is one of the major issues in the performance characterization of wireless communication systems. Various approaches exist in the literature for performance evaluation of mobile systems, especially the handoff phenomenon. However, since the probability of an ongoing call being dropped due to a handoff failure and the probability of a new call being blocked due to the temporary unavailability of an idle channel are main metrics that affect the performance of wireless cellular systems, it is essential to consider these systems for performability evaluation. In this paper, wireless cellular networks with failures and recovery are modelled. The service rates provided in each operative state are dependent on the number of originating calls as well as handoff calls coming from the neighbouring cells. The spectral expansion solution method together with an approach to handle the job dependent service rates is used. The numerical results are presented comparatively to validate the approximate approach presented previously.