| Directional antennas have been shown to provide significant improvement in the
physical-layer performance of wireless communication systems due to the antenna gain
and the interference-rejection capability they provide. Consequently they hold
considerable promise for improving the performance of wireless ad hoc networks, but only
if MAC-layer and network-layer protocols can be designed to make effective use of the
physical-layer advantages of directional antennas.
In this paper we present the design of a routing protocol that improves network performance by exploiting the availability of nodes with directional antennas in the network. In particular, it exploits the availability of routes with low mutual coupling made possible by the presence of nodes with directional antennas.
We begin by using Monte-Carlo simulations based on a simplified network model to demonstrate the potential benefit of employing such a routing
protocol, and we investigate how this potential benefit varies as a function of the percentage of nodes in the network that have directional antennas.
Following this, we describe the design of a distributed distance-vector based routing protocol that employs a modified metric, which captures
the amount of congestion in a path, to measure path cost. The basic idea is that as the nodes adjust their routes based on congestion levels, the routes used will converge towards a set of routes that have low mutual coupling. The benefit of this approach will be greater when a greater proportion of the nodes in the network have directional antennas since the mutual coupling between routes begins to decrease as this happens. |
| Arvind Swaminathan (S’99) was born in Chennai,
India, on February 4, 1978. He received the B.Tech. degree in electronics and communications engineering from the Regional Engineering College,
Calicut, India, in 1999 and the M.S. degree in
electrical engineering from Clemson University,
Clemson, SC, in 2002. For his M.S. thesis, he worked on techniques to improve the performance of serial acquisition in direct-sequence spread-spectrum packet radio networks. He is currently working towards the Ph.D. degree in electrical engineering at Clemson University, where he is a Research Assistant in the Wireless
Communications Laboratory. He is working on protocol design for ad hoc networks with directional antennas for his Ph.D. dissertation.
Mr. Swaminathan is a member of Alpha Epsilon Lambda. |