Multi-channel Hybrid Access Femtocells: A Stochastic Geometric Analysis

TL;DR

This paper analyzes the performance of hybrid access femtocells in two-tier networks using stochastic geometry, providing insights into the tradeoffs between subscribers and nonsubscribers in multi-channel spectrum sharing.

Contribution

It introduces a stochastic geometric framework for analyzing hybrid access in multi-channel femtocells, deriving distributions of key performance metrics.

Findings

Derived distributions of SIR and achievable rates for subscribers and nonsubscribers.

Quantified the performance tradeoff between subscriber and nonsubscriber access.

Validated analytical results with numerical simulations.

Abstract

For two-tier networks consisting of macrocells and femtocells, the channel access mechanism can be configured to be open access, closed access, or hybrid access. Hybrid access arises as a compromise between open and closed access mechanisms, in which a fraction of available spectrum resource is shared to nonsubscribers while the remaining reserved for subscribers. This paper focuses on a hybrid access mechanism for multi-channel femtocells which employ orthogonal spectrum access schemes. Considering a randomized channel assignment strategy, we analyze the performance in the downlink. Using stochastic geometry as technical tools, we model the distribution of femtocells as Poisson point process or Neyman-Scott cluster process and derive the distributions of signal-to-interference-plus-noise ratios, and mean achievable rates, of both nonsubscribers and subscribers. The established expressions are amenable to numerical evaluation, and shed key insights into the performance tradeoff between subscribers and nonsubscribers. The analytical results are corroborated by numerical simulations.