Improved Power-Delay Trade-off in Wireless Networks Using Opportunistic Routing

We study the benefits of opportunistic routing in wireless networks by examining how the power and delay scale as the number of source-destination (S-D) pairs in the network increases. The scaling behavior of conventional multi-hop transmission that does not employ opportunistic routing is also examined for comparison. Our results indicate that opportunistic routing can exhibit a better power–delay trade-off than that of conventional routing by providing up to a logarithmic boost in the scaling law. Such a gain is possible since the receivers can tolerate more interference due to the increased received signal power provided by the multi-user diversity (MUD) gain, which means having more simultaneous transmissions is possible. Computer simulations for both routing schemes are also performed, which show trends consistent with our analytical predictions. This work was in part supported by the IT R&D program of MKE/IITA [2008-F-004-01, 5G mobile communication systems based on beam division multiple access and relays with group cooperation]. The material in this paper was presented in part at the IEEE International Symposium on Information Theory, Nice, France, June 2007. W.-Y. Shin was with the School of EECS, KAIST, Daejeon 305-701, Republic of Korea. He is now with the School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138 USA (E-mail:[email protected]). S.-Y. Chung and Y. H. Lee are with the School of EECS, KAIST, Daejeon 305-701, Republic of Korea (E-mail: [email protected]; [email protected]). 2