Cloaking devices that render aircraft invisible to the naked eye remain in the realm of science fiction, for now, but the metamaterials research on which they may be based could enhance inflight connectivity on business and regional jets and commercial airliners in the next couple of years.
Kymeta Corp., a Redmond, Wash.-based start-up backed by Microsoft founder Bill Gates, is using metamaterials research to develop a new software-defined satellite aperture aimed at fixed, mobile and portable high-speed Ka-band broadband applications in the aeronautical, maritime and land-based markets.
A spinoff of Bellevue, Wash.-based patent-mining company Intellectual Ventures (IV), Kymeta was founded by Nathan Kundtz, a leading researcher in the field of metamaterials who has spent the past decade studying the technology. Along with Gates—Kymeta's largest financial backer and a member of the board—co-investors Liberty Global and Lux Capital helped close a $12 million round of financing last summer to launch Kymeta after the company gained exclusive license from IV for satellite applications of metamaterial surface-antenna technology.
In addition to developing a laptop-sized portable satellite hot-spot device to access high-speed Internet service absent Wi-Fi or mobile broadband signals, Kymeta plans to leverage the coming wave of satellite-based Ka-band broadband with a new fuselage-hugging surface antenna that has no moving parts, is roughly the size of a pizza box and uses only a tiny fraction of the power typically needed for phased-array antennas.
Known as the Aero Antenna, the satellite receiver relies on microscopic synthetic structures carefully engineered to embody properties not found in nature that can be used to manipulate and bend incoming electromagnetic radiation, such as light or radio waves.
Kymeta Chairman and CEO Vern Fotheringham says the ultra-thin structure of the surface antenna's waveguide is designed through a blend of circuit-board manufacturing, chip-fabrication and liquid crystal display techniques. In the case of the Aero Antenna, metamaterial surface elements are tuned to electronically point and steer a radio signal to low, medium or geostationary orbit, providing a continuous broadband link between satellite and aircraft.
Unlike mechanically steered gimbal apertures that are typically large, cumbersome, heavy and prone to wear, the Aero Antenna is a small, low-profile aerodynamic receiver that could be ideal for business jets and other light aircraft. Compared to phased-array antennas, which can require more than a kilowatt of power to drive the aperture, Kymeta expects to achieve comparable performance using just 0.5 watts to drive the beam. And because the antenna's metamaterial elements can be manufactured through lithographic printing techniques, the final product is expected to be low in cost.
“We think this is going to open up a lot of opportunities in the smaller aircraft market—single-aisle and business jets—and ultimately commercial aviation will find a lot of applications that could not be served due to form-factor and cost considerations,” Fotheringham says.
Last November, Kymeta entered into an exclusive two-year engineering contract with Inmarsat, an opportunity that will link the emerging technology to the new all-Ka-band Global Xpress satellite network slated to launch this year.
Aimed at the business aviation market, the Aero Antenna will be available only to Global Xpress users, providing an alternative to antenna hardware provided under an exclusive agreement signed last year with aerospace supplier, valued at $2.8 billion over the next 20 years.
“Honeywell prides itself on advanced technology and innovation and is pleased to support this research endeavor,” says Jack Jacobs, vice president of marketing and product management at Honeywell. “We are continuously looking to help deliver the most efficient and affordable connectivity products to the industry.”
On April 5, Kymeta tested the first link between a geosynchronous satellite and one of the company's metamaterial antennas using a receive-only aperture pointed at a Ka-band feed from a DirecTV satellite in geostationary orbit.
“It was the first time for a flat-plate, holographic, beam-forming, electronic software-defined antenna to actually see a signal from a satellite,” Fotheringham says of the test, which comprised eight of 32 subchannels that will eventually make up a full-scale aperture. “But the fact that it was seeing all the carriers and providing sufficient confirmation of link margin was a big deal.”
In the coming months, the company plans to refine the antenna's design and increase performance, culminating in a first transmission demonstration later this year.
“What we are working on now is to assemble a full-sized panel and actually close the link with a satellite,” Fotheringham says, adding that some of the challenges associated with metamaterial antenna technology have to do with efficiency, which improves at higher frequencies.
“The practical realities of scale direct us toward X-band and above,” he says. “We could build an S-band or L-band version of this. It'd just be really big, and there are better ways to do that at those frequencies.”
In addition to mobile, fixed and portable ground receivers, Fotheringham says Kymeta will explore the potential to develop metamaterial antennas for use on spacecraft. “We are exploring reconfigurable beams on satellites looking at the ground as well as links between satellites as we grow into maturity here,” he says.
Kymeta's first contract was a study initiative awarded last year by start-up fleet operator O3b, which this year will launch the first eight satellites of an initial 12-satellite constellation in medium Earth orbit designed for Ka-band broadband applications in the oil and gas exploration, cellular backhaul, maritime, military and cruise ship markets.
“The project involved providing them a tracking antenna solution to get them an alternative to mechanically steered infrastructure,” Fotheringham says. “The work study project came to conclusion a few months ago, and we're actively engaged with them to work to a prototype development here shortly.”
The company is also discussing the potential for metamaterial surface-antenna technology to extend the life of on-orbit satellites with Luxembourg-based SES, the world's second-largest telecommunications satellites fleet operator by revenue. Near the end of a satellite's service life, the gradual loss of onboard propellant leaves it circling in an inclined orbit from which ground tracking can become a challenge.
“Because most satellites still have plenty of performance left in their solar panels, we're thinking about the ability to allow a satellite to continue its useful life with a low-cost ground segment that can track the inclined orbit,” Fotheringham says.
In the meantime, Kymeta is expected to deliver the Aero Antenna to Inmarsat by November 2014, and separately plans to release its commercially available laptop-sized portable satellite receiver in the first quarter of 2015.
“We're getting a lot of pressure to go faster, but we're disciplined enough to stick to our plan and take a crawl-walk-run approach to becoming a viable contributor to the community,” Fotheringham says.
Watch an animation of Kymeta's antenna at work on our On Space blog: http://ow.ly/kaeqM