A network-aware MAC and routing protocol for effective load balancing in ad hoc wireless networks with directional antenna

Abstract

Use of directional antenna in the context of ad hoc wireless networks can largely reduce radio interference, thereby improving the utilization of wireless medium. Our major contribution in this paper is to devise a routing strategy, along with a MAC protocol, that exploits the advantages of directional antenna in ad hoc networks for improved system performance. In this paper, we have illustrated a MAC and routing protocol for ad hoc networks using directional antenna with the objective of effective load balancing through the selection of maximally zone disjoint routes. Zone-disjoint routes would minimize the effect of route coupling by selecting routes in such a manner that data communication over one route will minimally interfere with data communication over the others. In our MAC protocol, each node keeps certain neighborhood status information dynamically in order that each node is aware of its neighborhood and communications going on in its neighborhood at that instant of time. This status information from each node is propagated periodically throughout the network. This would help each node to capture the approximate network status periodically that helps each node to become topology-aware and aware of communications going on in the network, although in an approximate manner. With this status information, each intermediate node adaptively computes routes towards destination. The performance of the proposed framework has been evaluated on QualNet Network Simulator with DSR (as in QualNet) as a benchmark. Our proposed mechanism shows four to five times performance improvement over DSR, thus demonstrating the effectiveness of this proposal.Recently, several MAC protocols with directional antennas have been proposed in the context of ad hoc networks in order to improve the medium utilization with increased number of simultaneous communications. However, even if we have an efficient directional MAC protocol, it alone would not be able to guarantee good system performance, unless we have a proper routing strategy in place that exploits the advantages of directional antenna. Our major contribution in this paper is to devise a routing strategy, along with a MAC protocol, that exploits the advantages of directional antenna in ad hoc networks.Let us consider the scenario in Figure 1 where source S 1 is communicating with destination D 1 through N 1 and N 2 . At the same time, suppose another source S 2 also wants to communicate with destination D 2 . Suppose, there are three possible paths: {S }. If S 2 uses the first path that overlaps with the path used by S 1 , then simply using directional antenna cannot improve the routing performance. If S 2 uses the second path, then also routing performance will deteriorate because of the phenomenon known as route coupling [11,12,16]. Route coupling occurs when two routes are located physically close enough to interfere with each other during data communication. As a result, the nodes in those two routes are

Topology control for multi-channel multi-radio wireless mesh networks using directional antennas

“…A radio connected to an antenna array can dynamically switch to an antenna to transmit a packet to the specified direction this antenna is facing to [12,23]. Steerable-beam antennas can form beams pointing towards any specific direction [3,14,17,21,22]. In spite of its flexibility, the high cost and complexity in deployment make it difficult to provide a cost-effective solution for wireless mesh networks using smart antennas [5].…”

Directional MAC and routing schemes for power controlled Wireless Mesh Networks with adaptive antennas

“…While the above routing algorithms are designed for omnidirectional antennas, other ad hoc networks routing protocols that exploit directional antennas have been proposed in [11,13,16]. A routing protocol that selects maximally zone disjoint routes to minimize the effect of mutual interference of routes is presented in [16].…”

“…Some solutions [13][14][15] envisage the utilization of power control techniques to further enhance spatial reuse and to achieve higher wireless medium utilization. Several routing protocols have been also proposed for ad-hoc networks [11,13,16] and WMNs [17][18][19].…”

Performance Evaluation of Directional Adaptive Range Control in Mobile Ad Hoc Networks

“…Roy et al [21] proposed a link state based routing protocol using directional antenna to improve spatial reuse and minimize the effects of route coupling. Nasipuri et al [12] proposed techniques to reduce routing overhead by directional propagation of routing information and discussed the tradeoff between reduction in routing overhead and end to end delay of packets.…”