Open Access

Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications

EURASIP Journal on Wireless Communications and Networking20072007:053075

Received: 17 January 2006

Accepted: 27 December 2006

Published: 7 March 2007


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.


Authors’ Affiliations

Dipartimento di Elettronica e Informazione, Politecnico di Milano, Milano, Italy


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© O. Simeone and U. Spagnolini. 2007

This article is published under license to BioMed Central Ltd. 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.