Power-efficient directional wireless communication on small form-factor mobile devices

Wireless access is known to be power-hungry for mobile devices. A key reason is that devices radiate power in all directions and much of this power will not reach the destination. To address this waste, we present BeamSwitch, a multi-antenna system designed to realize directional communication efficiently. Unlike power-hungry and expensive beamforming, BeamSwitch requires only one transceiver. We provide an 802.11-compliant design and prototype of BeamSwitch. Our measurements show that with three passive directional antennas, BeamSwitch reduces the power consumption of a commercial 802.11 adapter by up to 20% and provide better quality under diverse propagation environments and extreme rotation.