Adaptive channel preemption model for small-cell embedded large-cellular networks

In this paper, we propose an adaptive channel preemption (ACP) model for small-cell embedded large-cellular (SCELC) networks. An SCELC network consists of a fixed base station (FBS) with large coverage and many embedded base stations (EBS) with relatively small coverage. This paper considers two aspects of channel allocation. First, by increasing one or more EBS cells within an FBS cell, the proposed ACP can reduce blocking probability of new calls. Second, to reduce dropping probability of handoff calls, ACP allows handoff calls to preempt on-going calls, when the latter are located in the overlapping area of two neighbor cells. For the purpose of validation, the proposed ACP scheme is evaluated by using 4-D Markov chains. The numerical results show that the proposed ACP scheme can substantially improve the system performance in terms of blocking and dropping probabilities.