Issue No. 02 - February (2008 vol. 7)
In this paper we propose a new MAC protocol for full exploitation of directional antennas in wireless networks. The protocol introduces a circular directional transmission of the RTS control packet, spreading around a station information about the intending communication. The stations that receive the directional RTS, using a simple scheme of tracking the neighbors' direction, defer their transmission towards the beams which could harm the ongoing communication. In this way, the proposed protocol takes advantage of the benefits of directional transmissions as the increase of spatial reuse and of coverage range. Additionally, it reduces the hidden terminal problem as well as the deafness problem, two main factors for the decrease of the efficiency of directional transmissions in ad-hoc networks. Performance evaluation of the protocol shows that it offers significant improvement in static as well as mobile scenarios, as compared to the performance of the proposed protocols that use omni or directional transmissions.
Wireless communications, MAC, directional antennas, IEEE 802.11
T. Korakis, G. Jakllari and L. Tassiulas, "CDR-MAC: A Protocol for Full Exploitation of Directional Antennas in Ad Hoc Wireless Networks," in IEEE Transactions on Mobile Computing, vol. 7, no. , pp. 145-155, 2007.