Microwave Power Transmission: Historical Milestones and System Components

Microwave power transmission (MPT) is the wireless transfer of large amounts of power at microwave frequencies from one location to another. MPT research has been driven primarily by the desire to remotely power unmanned aerial vehicles (UAVs) and by the concept of space solar power (SSP) first conceived by Dr. Peter Glaser of the Arthur D. Little Company in 1968. This paper attempts to reveal, in adequate chronological detail, many of the MPT milestones reached over the past 50 years, including those related to SSP. Key components to various MPT systems are presented as well as design schemes for achieving efficient MPT. Special focus is given to rectenna design since this particular MPT component has received the most attention from researchers over the last couple of decades.

I. Introduction

Wireless power transmission (WPT) can be subdivided into either near-field inductive-based WPT or far-field WPT. MPT comprises the microwave-frequency based subset of far-field WPT. In an MPT scenario, significant amounts of power are transferred from one location to another. MPT research has been driven primarily by the desire to remotely power unmanned aerial vehicles (UAVs) and by the concept of space solar power (SSP) first conceived by Dr. Peter Glaser of the Arthur D. Little Company in 1968 [1]. Most MPT breakthroughs have occurred under the umbrella of SSP. Fig. 1 shows a block diagram for the specific application of MPT pertaining to SSP. SSP is an MPT system with the addition of solar cells and magnetrons for microwave power generation. Fig. 1.

Diagram of an SSP–MPT system including a solar cell array, magnetron, circularly polarized (CP) phased array, and a CP rectenna array.