Cooperative Relaying in a Poisson Field of Interferers: A Diversity Order Analysis

TL;DR

This paper investigates the impact of interference and fading on cooperative relaying in wireless networks, revealing that spatial-contention diversity order is limited by MAC-phase constraints and varies with fading and interference correlation.

Contribution

It introduces a stochastic model for interference-limited networks and analyzes the diversity order of selection decode-and-forward relaying under various conditions.

Findings

SC-DO is always one due to MAC-phase limitations

In the BC-phase, SC-DO varies with fading and interference correlation

Without fading, SC-DO transitions between one and two depending on parameters

Abstract

This work analyzes the gains of cooperative relaying in interference-limited networks, in which outages can be due to interference and fading. A stochastic model based on point process theory is used to capture the spatial randomness present in contemporary wireless networks. Using a modification of the diversity order metric, the reliability gain of selection decode-and-forward is studied for several cases. The main results are as follows: the achievable \emph{spatial-contention} diversity order (SC-DO) is equal to one irrespective of the type of channel which is due to the ineffectiveness of the relay in the MAC-phase (transmit diversity). In the BC-phase (receive diversity), the SC-DO depends on the amount of fading and spatial interference correlation. In the absence of fading, there is a hard transition between SC-DO of either one or two, depending on the system parameters.