E.M. Sabbagh

Bio: E.M. Sabbagh is an academic researcher. The author has contributed to research in topics: Semiconductor & Capacitance. The author has an hindex of 1, co-authored 1 publications receiving 22 citations.

The History of Power Transmission by Radio Waves

Abstract: The history of power transmission by radiowaves is reviewed from Heinrich Hertz to the present time with emphasis upon the free-space microwave power transmission era beginning in 1958. The history of the technology is developed in terms of its relationship to the intended applications. These include microwave powered aircraft and the Solar Power Satellite concept.

Microwave Power Transmission: Historical Milestones and System Components

Abstract: 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.

High-Efficiency Harmonically Terminated Diode and Transistor Rectifiers

Abstract: This paper presents a theoretical analysis of harmonically terminated high-efficiency power rectifiers and experimental validation on a class-C single Schottky-diode rectifier and a class- F-1 GaN transistor rectifier. The theory is based on a Fourier analysis of current and voltage waveforms, which arise across the rectifying element when different harmonic terminations are presented at its terminals. An analogy to harmonically terminated power amplifier (PA) theory is discussed. From the analysis, one can obtain an optimal value for the dc load given the RF circuit design. An upper limit on rectifier efficiency is derived for each case as a function of the device on-resistance. Measured results from fundamental frequency source-pull measurement of a Schottky diode rectifier with short-circuit terminations at the second and third harmonics are presented. A maximal device rectification efficiency of 72.8% at 2.45 GHz matches the theoretical prediction. A 2.14-GHz GaN HEMT rectifier is designed based on a class-F-1 PA. The gate of the transistor is terminated in an optimal impedance for self-synchronous rectification. Measurements of conversion efficiency and output dc voltage for varying gate RF impedance, dc load, and gate bias are shown with varying input RF power at the drain. The rectifier demonstrates an efficiency of 85% for a 10-W input RF power at the transistor drain with a dc voltage of 30 V across a 98-Ω resistor.

Experiments Involving a Microwave Beam to Power and Position a Helicopter

Abstract: This paper describes two different experiments involving a microwavebeam and a helicopter. The first experiment utilized a CW microwavebeam to supply a small helicopter with all of the power that it neededfor its propulsion. The second experiment utilized an unmodulated CW microwave beam for supplying a position reference to the helicopterer with respect to roll, pitch, yaw, and horizontal translation. Thesecond experiment also involved the construction of a fully articulatedhelicopter and a complete control system carried on board theli-helicopter. The paper also attempts to relate the small scale experimentsand the present state of component technology to practical, full scalemicrowave-powered helicopter systems that can operate at altitudesof up to 50 000 feet.

Electronic and mechanical improvement of the receiving terminal of a free-space microwave power transmission system

Abstract: Significant advancements were made in a number of areas: improved efficiency of basic receiving element at low power density levels, improved resolution and confidence in efficiency measurements mathematical modelling and computer simulation of the receiving element and the design, construction, and testing of an environmentally protected two-plane construction suitable for low cost, highly automated construction of large receiving arrays.