Analysis of a cooperative strategy for a large descentralized wireless network

ANDRES ALTIERI; LEONARDO REY VEGA; CECILIA GALARZA; PABLO PIANTANIDA

IEEE-ACM TRANSACTIONS ON NETWORKING

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2014 vol. 22 p. 1039 - 1051

1063-6692

This paper investigates the benefits of cooperation and a relay activation strategy in a large wireless network with multiple transmitters in which some nodes, through the use of a nearby relay, cooperate using the decode-and-forward protocol, and others use direct transmission. The network is modeled as an independently marked Poisson point process and the source nodes may choose their relays from the set of inactive nodes. Although cooperation can potentially lead to significant improvements in the performance of a communication pair, relaying causes additional interference in the network, increasing the average noise that others nodes see. We investigate how source nodes should balance cooperation vs. interference to obtain reliable transmissions, and for this purpose we study and optimize a relay activation strategy with respect to the outage probability. Surprisingly, in the high reliability regime, the optimized strategy consists on the activation of all the relays or none at all, depending on network parameters. We provide a simple closed-form expression that indicates when the relays should be active, and we introduce closed form expressions that quantify the performance gains of this scheme with respect to a network which only uses direct transmission.