EURASIP Journal on Wireless Communications and Networking
Volume 2007 (2007), Article ID 53075, 7 pages
doi:10.1155/2007/53075
Research Article

Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications

O. Simeone and U. Spagnolini

Dipartimento di Elettronica e Informazione, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milano 20133, Italy

Received 17 January 2006; Revised 13 November 2006; Accepted 27 December 2006

Academic Editor: Christian Hartmann

Copyright © 2007 O. Simeone and U. Spagnolini. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Optimal multihop routing in ad hoc networks requires the exchange of control messages at the MAC and network layer in order to set up the (centralized) optimization problem. Distributed opportunistic space-time collaboration (OST) is a valid alternative that avoids this drawback by enabling opportunistic cooperation with the source at the physical layer. In this paper, the performance of OST is investigated. It is shown analytically that opportunistic collaboration outperforms (centralized) optimal multihop in case spatial reuse (i.e., the simultaneous transmission of more than one data stream) is not allowed by the transmission protocol. Conversely, in case spatial reuse is possible, the relative performance between the two protocols has to be studied case by case in terms of the corresponding capacity regions, given the topology and the physical parameters of network at hand. Simulation results confirm that opportunistic collaborative communication is a promising paradigm for wireless ad hoc networks that deserves further investigation.