Spatial and Social Paradigms for Interference and Coverage Analysis in Underlay D2D Network

TL;DR

This paper models interference in underlay D2D networks using spatial and social distributions, revealing how power control can enable dense D2D deployment without harming cellular coverage.

Contribution

It introduces a novel combined spatial-social Poisson point process model for interference analysis in D2D networks, providing bounds on coverage probability.

Findings

Power control maintains cellular coverage in dense D2D networks.

Social relationships significantly impact interference and coverage.

Bounds on coverage probability are derived using special functions.

Abstract

The homogeneous Poisson point process (PPP) is widely used to model spatial distribution of base stations and mobile terminals. The same process can be used to model underlay device-to-device (D2D) network, however, neglecting homophilic relation for D2D pairing presents underestimated system insights. In this paper, we model both spatial and social distributions of interfering D2D nodes as proximity based independently marked homogeneous Poisson point process. The proximity considers physical distance between D2D nodes whereas social relationship is modeled as Zipf based marks. We apply these two paradigms to analyze the effect of interference on coverage probability of distance-proportional power-controlled cellular user. Effectively, we apply two type of functional mappings (physical distance, social marks) to Laplace functional of PPP. The resulting coverage probability has no closed-form expression, however for a subset of social marks, the mark summation converges to digamma and polygamma functions. This subset constitutes the upper and lower bounds on coverage probability. We present numerical evaluation of these bounds on coverage probability by varying number of different parameters. The results show that by imparting simple power control on cellular user, ultra-dense underlay D2D network can be realized without compromising the coverage probability of cellular user.