A Probabilistic Distance-Based Modeling and Analysis for Cellular Networks With Underlaying Device-to-Device Communications

Device-to-device (D2D) communications in cellular networks are promising technologies for improving network performance. However, they may cause severe intra/inter-cell interference that can considerably degrade the performance of cellular users, and vice versa. Therefore, interference analysis has been one of the most important research topics in such a system. Focusing on an uplink resource reusing scenario, this paper presents a framework based on a probabilistic distance and path-loss model to obtain the distributions of signal, interference, and further Signal-to-Interference-plus-Noise Ratio (SINR), based on which, the performance metrics that are functions of SINR can be analyzed, such as outage probability and capacity. Different from the previous work, this proposed framework: 1) obtains interference and SINR distributions for both cellular and D2D communications, through which insights into their performance metrics and mutual influence are provided and 2) has no limitations on cell shapes, except that they are approximated by polygons or circles. The framework can also be applied to a downlink reusing scenario. Our results indicate that the developed framework is helpful for network planners to effectively tune the network parameters, and thus to achieve the optimum system performance for both cellular and D2D communications.

I. Introduction

To address the big challenges raised by the tremendous increase of mobile devices and explosive growth of data traffic demands in cellular networks [1], a lot of technologies have been studied and developed in the last decade, such as white space [2], cognitive radio [3], femtocells [4], Device-to-Device (D2D) communications [5], etc. Recently, great efforts have been devoted from both academia and industry to the research and development of D2D communications, as believed to be one of the promising technologies to improve network performance in several aspects. Specifically, by allowing the direct communications between nearby User Equipments (UEs) without traversing the Base Station (BS) or core network, not only are the transmission delay and power reduced, but also the network coverage can be extended. More importantly, D2D communications in cellular networks occurring on either the cellular or unlicensed/unused spectrum bring a great chance to improve network capacity and spectrum efficiency.