Microwave and Millimeter Wave Power Beaming

Abstract

Power beaming is the efficient point-to-point transfer of electrical energy across free space by a directive electromagnetic beam. This paper clarifies the basic principles of power beaming in simple terms, and proposes a benchmarking methodology for improving the comparative assessment of power beaming systems and technology. An in-depth historical overview tracing the worldwide progress in microwave and millimeter wave (mmWave) experimental demonstrations over the past 60 years shows clear evidence of a significant increase in activity during the last 5 years. In addition, a review of progress in scalable rectenna arrays for the reception of microwave power beaming shows sufficient maturity for new research to initiate on the ruggedization, productization, and system integration aspects of the technology. A review of regulatory issues including spectrum management and safety indicates the need for additional technical solutions and international coordination. Breaking results reported in this paper include 1) data from the first in-orbit flight test of a solar-to-RF “sandwich module”, 2) the construction of multiple US in-orbit demonstrations, planned for 2023 launch, that will demonstrate key technologies for space-based solar power, and 3) a 100-kW mmWave power beaming transmitter demonstrating inherent human life safety.