Performance evaluation of multiple access protocols for ad hoc networks using directional antennas

In this paper, we introduce a novel reservation based multiple access protocol for ad hoc networks using directional antennas. First, we investigate the limitations of the extreme reservation schemes, namely omni-directional and directional reservations. We highlight the trade-off between spatial reuse (favors directional reservation) and control/data packet collisions (favors omni-directional reservation). Next, we show that the so-called hybrid reservation schemes fail to balance the trade-off as well. Therefore, we introduce a novel algorithm that balances the aforementioned trade-off via sending reservation messages that carry information about the required direction of transmission, in all unblocked directions. In addition, we introduce candidate techniques for handling new types of collisions inherent to directional antennas. Finally, we conduct a simulation study that shows considerable performance gains of the proposed scheme over the omni-directional, directional, and hybrid reservation paradigms.