The saber microwave-powered helicopter project and related WPT research at the University of Alaska Fairbanks

This paper describes the current status of three projects at the University of Alaska Fairbanks with potential applications to Solar Power Satellites (SPS). The Semi-Autonomous BEam Rider (SABER) project is a model helicopter powered by a 1 horsepower electric motor and a rotor with a diameter of 1.15 m. It receives the power necessary to hover from a 1 kW microwave transmitter operating at 2.45 GHz. This project is intended to provide a test bed for development of Wireless Power Transmission (WPT) technology and an easily transportable demonstration of this technology. The power is received by an array of rectenna elements mounted beneath the helicopter. The ultimate goal is to integrate sensor and control subsystems onto the helicopter to measure the helicopter’s attitude and position, and allow it to autonomously hover over the incident microwave beam. A second project consists of the continued refinement of a Magnetron Directional Amplifier (MDA) to provide an efficient, high power microwave source with independent control of phase and amplitude. Several MDA modules may be combined to provide an electronically-steerable phased array antenna in the future. A third project consists of computer simulations and optimization of sparse array antennas for SPS applications.