Gearing up to have its Ka-band antenna system installed on JetBlue Airways’ fleet and some 200 aircraft operated by United Airlines, ViaSat says it is about to prove naysayers wrong about the capabilities of dual purpose Ku-Ka radomes.
Some industry stakeholders have cited challenges in developing Ka radomes, suggesting that they are more expensive than Ku, and bulkier to boot.
Ka radomes “are slightly more expensive”, confirms Lance Diamond, ViaSat director of business development at antenna systems. But the cost is “not a large percentage of added expense; it’s reasonable, you don’t just double the price of [a Ku] radome”.
More significant, he says, is the fact that the radome for JetBlue and United – which will house both Ka and Ku antennas to support inflight high-speed Internet and live television, respectively – is meeting ViaSat’s expectations.
ViaSat’s installation and certification partner, JetBlue subsidiary LiveTV, “is actually the one that is contracting for the radome. We provided the specifications for it that let us meet total RF requirements and they went out and are procuring it themselves,” says Diamond.
LiveTV contracted General Dynamics – a well-known name in the world of defence – to supply the radome. General Dynamics has 60 years of experience in constructing radomes; it makes solid laminate and sandwich radome structures with honeycomb or foam cores. The company previously manufactured the radome for Boeing’s Ku-band Connexion inflight high-speed Internet service (Lufthansa still flies some aircraft with CBB’s MELCO antennas and General Dynamics’ radomes).
Diamond says ViaSat had a lot of requirements for the specs of the radome that will be installed on aircraft operated by JetBlue and United, “but the main two for Ka performance are transmission loss – how much energy you get through the radome – and the other important spec is cross polarisation because we want to maintain the circular polarisation of the Ka signal. We are currently testing a radome [from General Dynamics] and it is testing out per our specs.”
ViaSat declined to say what materials are being used for the radome, calling such information “proprietary”, though Diamond notes: “There are materials and wall stack ups for how you layer the material that allow you to have a consistent radome that allows you to operate over Ku and Ka.”
He notes, candidly, that, “Ku is a much easier problem in that you can track the polarisation rather than have to live with what you get through the radome.”
I asked Diamond if, in developing the antenna system for Ka-band inflight connectivity – and designing the specs for the dual Ku-Ka radome – the company encountered any unforeseen challenges. “I think we’ve learned a lot. Some things that were new that we didn’t anticipate, but they were all solvable problems. In the beginning there were a lot of bold statements that you can’t do a Ku-Ka radome. We’re going to be flying them. Those statements are soon to be proven wrong,” he says.
ViaSat director of mobile broadband Don Buchman adds: “We’re gearing up, getting out of the lab side of the certification testing now and should be doing our first install [on JetBlue] at the end of this year or the beginning of next year.”
ViaSat claims that its inflight high-speed Internet service, dubbed Exede, is capable of delivering 12 Mbps “or more” to individual passengers, though airlines will ultimately decide what level of service to offer passengers. JetBlue has previously said it will offer the Exede Wi-Fi service free-of-charge on the first 30 aircraft installed with the Ka-band-supported system.
[Editor's note: The ARINC Project Initiation/Modification (APIM) project 12-009 is addressing Ku-band/Ka-band antenna radome interfaces. Support for the activity has come from multiple parties, including Saint-Gobain, ViaSat, Inmarsat, Row 44 and others. The next meeting will be held 15-17 January in Cocoa Beach, Florida.]