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Wireless multihop networks are gaining popularity in different forms of applications like mesh networks including both wireless LAN and wireless MAN, sensor networks, and wireless backbone. However, a fundamental problem that distinguishes wireless networks from wired networks is the mutual interference between routes within the proximity of each other. All the nodes in the network uses the same channel to communicate and a collision cannot be detected as is done very easily in wired network. This phenomenon is known as route coupling and it restricts the possibility of occurrence of simultaneous communications along the coupled routes. In this context, the use of directional antenna, having smaller transmission beam-width compared to omni-directional antenna, helps to easily decouple interfering routes, and improves network performance through Space Division Multiple Access (SDMA). With recent progress in signal processing and antenna technologies, smart beamforming antennas have become feasible at cheaper prices, making them an attractive replacement to omni-directional antennas. Utilizing directional antenna in PHY layer require an efficient directional MAC layer protocol. 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. So an efficient directional MAC layer protocol with an adaptive routing strategy is proposed that exploits the advantages of directional antenna in ad hoc networks through the selection of optimally zone-disjoint shortest routes. Zone-disjoint routes would minimize the effect of route coupling and improve the overall network performance. The proposed strategy ensures effective load balancing and is applied to design and implement both single path and multipath routing protocols in ad hoc networks with directional antennas. Last modified 7 December 2007 at 10:50 pm by sahad |