Design and Development of Wireless Power Transmission for Unmanned Air Vehicles

Abstract

This thesis is an exploration of microwave wireless power transmission (WPT) for micro-air vehicles (MAVs). WPT, converting radio frequency (rf) power into usable direct current (dc) power, can be implemented with a rectifying antenna, or rectenna. The emphasis of this thesis is on the simulation of rectenna efficiency and measurement of experimental hardware. In this thesis, power reflection in the rectifier matching circuit was investigated by a series of simulations using Agilent Advanced Design System (ADS). Tuning elements were added and adjusted in order to optimize the efficiency. A maximum efficiency of 57 per cent was obtained at 10 gigahertz (GHz) with 200 mW input to the rectenna. A full-wave rectenna was built and hardware experiments were conducted to measure the efficiency of the WPT and characterize the behavior of the circuit. The design is optimized for an input power of 200 mW but, because of hardware limitations, only low-input power levels (about 1 mW) could be tested. A comparison of measurement and simulation results is given, and possible reasons for the differences are discussed.