The impact of directional antennas on energy-aware, session-based multicasting in ad hoc wireless networks

In our earlier studies we developed several algorithms for broadcast and multicast tree construction for session traffic in all-wireless networks. The Broadcast Incremental Power (BIP) and Multicast Incremental Power (MIP) algorithms are "node-based" schemes that exploit the "wireless multicast advantage" provided by the use of omnidirectional antennas. In this paper, we study broadcasting and multicasting when directional antennas are used. Alternative approaches to implementing algorithms based on BIP and MIP are presented, and their energy efficiency is evaluated. It is shown that considerable savings in energy can be achieved by using directional antennas, especially by using the Directional-BIP (D-BIP) and Directional MIP (D-MIP) schemes, which exploit directional antenna properties throughout the tree construction process.