A new queueing model for spectrum renting in mobile cellular networks

Spectrum renting is an operation practice that can be applied to relieve the temporary capacity shortages of a specific service area in wireless cellular networks. However, works in the literature do not take into account the specific feature of the present wireless technology. That is, the separate blocks of user channels are defined in each frequency band in the current standards for public mobile cellular networks, and each block should be controlled by a single network operator. This paper is the first attempt to model the spectrum renting policies and the call admission control in a realistic way. The comparison between a queueing model and a simulation model confirms that the proposed queueing model incorporating exponentially distributed call durations can be used to evaluate the performance of mobile cellular networks with call holding times following the lognormal distribution as well. Numerical results show that the variants of the Fractional Guard Channel Policy provide an efficient tool to guarantee the grade of service of handover calls at the expense of increased blocking probability of fresh calls. Furthermore, only spectrum renting can be used to decrease the blocking probability of fresh calls without compromising the grade of service of handover calls. (C) 2012 Elsevier B.V. All rights reserved.