Exploring the Multicast Lifetime Capacity of WANETs with Directional Multibeam Antennas

We explore the multicast lifetime capacity of energy-limited wireless ad hoc networks using directional multibeam antennas by formulating and solving the corresponding optimization problem. In such networks, each node is equipped with a practical smart antenna array that can be configured to support multiple beams with adjustable orientation and beamwidth. The special case of this optimization problem in networks with single beams have been extensively studied and shown to be NP-hard. In this paper, we provide a globally optimal solution to this problem by developing a general MILP formulation that can apply to various configurable antenna models, many of which are not supported by the existing formulations. The multicast lifetime capacity is then quantitively studied by simulations. The experimental results show that using two-beam antennas can exploit most lifetime capacity of the networks for multicast communications.