Edge Caching for Coverage and Capacity-aided Heterogeneous Networks

TL;DR

This paper models and analyzes the impact of edge caching in heterogeneous cellular networks, revealing how cache size and rate splitting influence network performance and fairness.

Contribution

It introduces a new model for cache-enabled small cells in HCNs and derives approximate expressions for average delivery rate considering inter- and intra-tier dependence.

Findings

Cache size significantly improves small cell delivery rates

Rate splitting causes non-linear performance variations

Adjustments are needed for rate fairness among users

Abstract

A two-tier heterogeneous cellular network (HCN) with intra-tier and inter-tier dependence is studied. The macro cell deployment follows a Poisson point process (PPP) and two different clustered point processes are used to model the cache-enabled small cells. Under this model, we derive approximate expressions in terms of finite integrals for the average delivery rate considering inter-tier and intra-tier dependence. On top of the fact that cache size drastically improves the performance of small cells in terms of average delivery rate, we show that rate splitting of limited-backhaul induces non-linear performance variations, and therefore has to be adjusted for rate fairness among users of different tiers.