Metalens design for high-efficiency wireless power transfer

2021 ELE Engineering Design Project (MA03)

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Faculty Lab Coordinator

Marco Antoniades

Topic Category

Signal Processing / Communication

Preamble

Wireless power transfer – the sending and receiving of energy across vast distances without wires or cables in between – represents an unparalleled opportunity for radical innovation including indefinite flight (powered wirelessly from ground), removing fossil fuel use from the skies to combat climate change, and ultra-secure data transmission for new paradigms in cyber-security. However, physical limitations of antennas including non-directive beams, off-target effects, and constricted down-scaling have hindered implementation. New technology concepts are now available which will make possible these transformative capabilities, in part by using metamaterial lenses (metalenses). A metalens is a composite material with a zero or negative index of refraction that can steer electromagnetic radiation in directions not otherwise found in nature, resulting in parallel, plane wave radiation that can be designed with no side lobes, and which can be scalable to any size. Note: Expert industry support is available from VanWyn Inc. to consult and mentor on this project.

Objective

Design and build a metalens that consists of a wireless power transmitter capable of parallel, plane wave radiation without side lobes, and an omnidirectional receiver. The solution will serve as a proof-of-concept or (time permitting) a prototype to deliver power vertically to a drone at 120 meters altitude to enable indefinite flight and station-keeping.

Partial Specifications

1. The overall size of the transmitter and receiver will be defined based on the frequency chosen and required power output.
2. The frequency of operation will be limited to Industrial, Scientific and Medical (ISM) bands, preferably either 2.45 GHz or 5.8 GHz.
3. The transmitter will deliver wireless power with extremely high gain, a minimum of (i) one meter distance, (ii) for at least one minute of continuous transmission, (iii) at a bare minimum of 1% total system efficiency. No minimum amount of power is mandated. The transmitter and receiver should be high efficiency (70%+).
4. Ideal results include: 120 meters distance; 100 Watts of power delivered; continual operation, 90%+ transmitter and receiver efficiency; electronic beam steering; and multiplexing (multiple signals within one carrier beam).
5. The transmitter has to conform to standard regulatory requirements such as Safety Code 6 of Health Canada for power levels emitted by wireless devices.
6. The design should maximize the overall efficiency of the unit by maximizing the radiation efficiency of the antenna and the efficiency of the receiver.

Suggested Approach

The students should become familiar with metamaterials in general and state-of-the-art in metalens designs including modeling software used and existing designs within the literature, specifically for wireless power transfer with (i) parallel, plane wave radiation and zero side lobes, plus (ii) omnidirectional receiving. Additional recommended reading includes: antenna physics; wave propagation; plane waves; ISM bands, power management and distribution, radiation detection tools, PCB design and fabrication, regulatory bodies such as Health Canada, Safety Code 6, and standard AC-DC rectifying antenna (“rectenna”) designs. Features such as device size and dimensions, material selection, efficiency (for each component as well as total system), amount of transmitted power and performance will be emulated using industry-standard electromagnetic simulation software and evaluated within a laboratory environment.

Group Responsibilities

The group should work collaboratively as a team to define the specifications for each component of the power transmitter and receivers in order to achieve the overall objective of the project. Each component will be designed separately, which will then be integrated to form a final working prototype. Students may work together in small sub-groups on specific components, but one student should be responsible for the completion of each of the following tasks:

Student A Responsibilities

Metalens power transmitter antenna design and fabrication

Student B Responsibilities

Metalens power receiver antenna design and fabrication

Student C Responsibilities

Power management and distribution design and fabrication

Student D Responsibilities

Rectifying antenna design and 3D printing

Course Co-requisites

ELE 861 – Microwave Engineering

To ALL EDP Students

Due to COVID-19 pandemic, in the event University is not open for in-class/in-lab activities during the Winter term, your EDP topic specifications, requirements, implementations, and assessment methods will be adjusted by your FLCs at their discretion.