Link Establishment in Ad Hoc Networks Using Smart Antennas
Vikram Dham, Luiz A. DaSilva, Scott F. Midkiff, A. Annamalai · VTechWorks (Virginia Tech) · 2003
Traditionally medium access control protocols for ad hoc networks have been designed for nodes using omni directional antennas. Through the use of directional antennas, it is possible to obtain higher efficiency. In this thesis we investigate the impact of these antennas on aggregate throughput and end-to-end delay. The use of omni-directional antennas not only results in lower power efficiency, but also decreases network efficiency due to interference caused by the transmission of packets in undesired directions. This thesis explores the effect of using smart antennas and proposes a signaling mechanism for forming the extended links using the network layer. For the performance assessment of the wireless networks using directional antennas, baseline models of phased array antenna and channel have been developed using the discrete event simulator OPNET Modeler 8.0. Simulation scenarios have been created for single hop as well as multihop networks. From the results of the simulation we observe that although the nodes forming the extended link experience decrease in end-to-end delay, the data successfully transmitted using extended link is correlated to the spatial distribution of nodes. III Acknowledgements I would like to thank Dr Luiz DaSilva, my academic and research advisor for his guidance and assistance throughout the project, without which this work wouldn't have been possible. I am highly indebted to him for his infinite patience and understanding. I would also like to thank my committee members, Dr. Scott Midkiff and Dr. Annamalai Annamalai for serving on my committees and for their assistance and support for this thesis.