Optimal beam scheduling for multicasting in wireless networks

We consider the problem of efficient link-layer multicasting in wireless networks with switched beamforming antennas. The inherent tradeoff between multicasting and beamforming – the broadcast advantage of low-gain omni-directional transmissions versus the high-gain but spatially restricted transmissions of beamforming antennas – makes this problem especially challenging. In this paper, we design and evaluate optimal algorithms, and easy-to-implement greedy algorithms with performance guarantees, that generate and schedule efficient beam patterns for multicast transmissions. These algorithms are built upon the novel usage of composite beams that provide a knob to control the operating point of the tradeoff curve. This is in contrast to the sub-optimal usage of either purely directional or omni-directional beams by existing schemes. We further consider two models for composite beam pattern generation: one in which transmit power is (a) equally split, and (b) asymmetrically split ...

• Type: Conference
• Year: 2009
• Where: MOBICOM
• Authors: Karthikeyan Sundaresan, Kishore Ramachandran, Sampath Rangarajan
• Keywords: Beamforming, Communications, Composite Beam, Low-gain Omni-directional Transmissions, MOBICOM 2009