More than three billion people in the world still don’t have Internet access. What if providing it were as simple as sticking a thin panel on the back of a tablet?
Engineering professor George Eleftheriades (ECE) and his team are working on that panel—they’ve designed a new metamaterial surface that can focus electromagnetic waves into a concentrated beam.
Their work was published this week in the leading journal Nature Communications.
“The beams that come off of this surface are like lasers—we can send this energy very far, maybe even all the way to a satellite in orbit,” says Eleftheriades. “You could have one on your roof instead of a big satellite dish.”
Their current prototype looks like a patterned ceiling tile, and this sort of inexpensive and thin antenna could allow you to receive a signal, such as broadband Internet, directly from space—no bulky, expensive and immobile infrastructure required.
The real innovation in Eleftheriades’s design is making the antenna flat, thin and uniformly illuminated. Picture the big rooftop satellite dish—it has a tripod-shaped structure at its centre that beams the signal down onto the dish, so it can be reflected back as a focused beam. That tripod needs to be a certain distance from the surface in order to focus the reflected beam, making the whole set-up necessarily bulky and large.
Metamaterials are engineered materials not found in nature, and Eleftheriades and his group, post-doctoral fellow Dr. Ariel Epstein and PhD candidate Joseph Wong, have designed what is essentially a printed circuit board with very specific electric and magnetic properties. His metamaterial antenna can ‘capture’ signal from a source very close to its surface, and shape that signal into a highly concentrated beam.
“With this design, we’ve optimized the way the antenna works to overcome the traditional compromise between the size of low-profile aperture antennas, and the strength of their beams,” says Eleftheriades.
The current prototype is two centimetres thick, and Eleftheriades and his group are now working on designing something even thinner and even more sharply focused.
“Many companies are working toward providing Internet to the rest of the world,” says Eleftheriades. “They’re looking for low-cost, low-profile, antennas to communicate with statellites, and they have to be portable. We think this design is a step toward that.”