Product Focus: Antennas

By Ed McKenna | March 1, 2012
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With growing demand for in-flight connectivity, the question is increasingly not if but when operators will opt to equip their aircraft with broadband service. For antenna developers, this trend should yield opportunities for all operators — from global airlines to the individual general aviation pilot. However, the market remains in flux with technology providers offering a variety of approaches and operators carefully weighing technology, cost, coverage and timing issues as they make their decisions.

The catalyst for the growth of in-flight broadband is escalating connectivity demands. “From where we sit, the key trend is connectivity all the time, in all places,” said Raju Chandra, vice president, marketing and sales at Tecom Industries, based in Thousand Oaks, Calif. Tecom is supplying its Kustream 1000 antenna systems to Row 44, which is supplying Ku-band broadband services to Norwegian Air Shuttle and Southwest Airlines.

This trend is “manifesting itself both in the commercial … and military domains,” Chandra said. On commercial aircraft, it is reflected in the increased passenger use of the digital devices, such as tablet computers, whereas for military it is needed to handle the volume of video data generated on aircraft and a growing fleet of unmanned aerial systems (UAS).

The connectivity trend is not limited to high-end operators. Using Inmarsat SB200, “our Aviator 200 service can be put in an aircraft as small as a (Socata) TBM 700,” said Andy Beers, director of aeronautical sales, Americas at Thrane & Thrane. The Aviator 200 system, which offers broadband data speeds of up to 200 kilobits per second via small, low gain antennas, is one of a family of broadband products the company offers for general aviation and business aircraft.

For airlines in the U.S. market, in-flight broadband is now a “competitive requirement,” said Amy Cravens, senior analyst at the research and consulting firm In-Stat. Late last year, the firm released a study showing the number of airplanes equipped with broadband was up and, importantly, the “take rates” by passengers of the service “have increased significantly, moving from an average of 4 percent in 2010 up to 7 percent in 2011.”

This growth has spurred competition between a varied group of broadband providers. A leader in the U.S. market, Gogo (formerly Aircell) said its system is deployed on more 1,327 aircraft from nine U.S. and Canadian airlines, operates an air-to-ground network within the United States. It has used two small blade antennas from Comant Industries, a Cobham subsidiary based in Fullerton, Calif., to establish connectivity. Gogo is set to launch a service upgrade, ATG-4, which it says will “improve per aircraft capacity by approximately four times current performance through the addition of Directional Antenna, Dual Modem and EV-DO Rev. B technologies.” The company has also signed up to be an early user of Inmarsat-5 Global Xpress Ka network, which will allow it to expand its operations into satellite communications in the next few years. Aircell expects its Ka-band technology to be available for the continental United States in 2013 and globally by 2015. (In 2011, Aircell split its business aviation and commercial aviation businesses; the business aviation unit is called Aircell, while the commercial aviation unit is called Gogo.)

When it comes to satellite communications in the aircraft, a cadre of technology companies, including antenna providers Esterline CMC Electronics, Honeywell, Rockwell Collins, Tecom, Thales and Thrane & Thrane, are reselling services from networks including Iridium, Inmarsat’s SwiftBroadband (SBB) and Swift 64 that tap the L-band spectrum satellites.

Along with Row 44, Panasonic Avionics of Lake Forest, Calif., offers Ku-band based services with their much throughput capacity. SwiftBroadband’s current top end data rate is 432 kilobits per second per channel, while Row 44 claims transmission rates of up to 11 Megabit per second. Panasonic, which provided its exConnect Ku-band service to re-launch Lufthansa’s FlyNet services in 2010, inked deals with Etihad Airways and United Airlines last year adding 500 aircraft to its user base, and expects to have 1,000 installs by the end of FY 2015, the company said.

The antenna systems have been “the hardest part” of development process, said Todd Hill, director, technical operations, Global Communications Services at Panasonic Avionics. “We have probably been through seven or eight antenna designs over the last eight or nine years for different Ku applications in television and two-way data,” he said. The difficulty comes with balancing the different requirements, such as the need for it to be lightweight, capable of being manufactured in a factory and easily maintainable, he said. “We think we ended up with a really good design … (and) are happy and proud that we have got it up and running have it certified,” he said. Along the way, the company had worked with Starling Advanced Communication and EMS Technologies (now Honeywell), but “we are actually moving to bring the antenna production in house (now),” he said.

The growing appetite for capacity, particularly in the air transport category, is also sparking a “move to higher bandwidth services, such as higher data rates on L-band and Ka-band,” said Fred Cahill, vice president of Cobham Antenna Systems. Slated to be up and running by the end of 2014, Inmarsat’s Global Xpress is projected to offer customers transmission rates of up to 50 megabits per second.

The introduction of Global Xpress has caused some customers to “reassess (or) defer broadband cabin upgrade decisions,” but others have “proceeded with SwiftBroadband solutions now since SBB provides more than enough bandwidth” for the needs, said Alan Hnatiw, product manager, aeronautical communication products, Esterline CMC Electronics.

The Ka-band service is likely to have “little impact on markets for cockpit communication,” but in the cabin, growing bandwidth requirements will drive in the “medium to long term... a move from of L-band to Ka-band,” said Cahill.

This transition to Ka will not be without technology challenges or changes for antenna systems. For example, “the need for increased tracking and pointing accuracies” caused by using the spectrum will “result in higher tolerances and (the need for) more sophisticated control systems,” said Cahill. In addition, “higher RF losses at higher frequencies (will result) in architectural system layout and radome design challenges,” he said.

‘From where we sit, the key trend is connectivity all the time, in all places.’ — Raju Chandra, vice president, marketing and sales at Tecom Industries

Costs or related business issues, not technical adjustments, are the critical challenges, according to Hnatiw. “How much will customers pay? How will that revenue be divided up between the players? And (will) … that be enough to support a business case,” he said. “The industry has many past failed attempts, will this time be different?”

“Ka is expensive,” said Beers. “The antennas … are bigger and more complex and have to do more things to interact with the Ka signal.” The cost, size and complexity issues will keep interest in Ka products at the commercial aviation level, or at least the largest of the VIP and business aircraft.

Even as the industry considers the high price of Ka, there is a strong drive, especially among the airlines, to reduce costs and boost efficiency in almost every area. This includes a requirement “for smaller, lighter antennas with increased reliability and lower power consumption,” said Cahill. One way to reach this goal is using “technology … to reduce weight, including lightweight dielectric materials and composite structures,” he said. Reliability can be increased “through the use of fewer components and advanced production techniques in pre-stress screening.”

CMC’s approach to this issue is to “provide antennas that are ‘purpose-built’ for an application,” said Hnatiw. “We provide the CMA-2102SB High Gain Antenna (HGA) for use on wide-body long haul aircraft and our smaller CMA-2200SB Intermediate Gain Antenna (IGA) for narrowbody aircraft,” Hnatiw said. Both support multi-channel SwiftBroadband.

Another way to reduce the footprint of these components is through the use of multifunction antennas, such as Cobham’s Satcom SB200, which combines GPS and Inmarsat antennas in the same package. In general terms, “there is an increase in interest (in these antennas), but there is also a lack of definition regarding common solutions for the commercial airline industry,” said Cahill. In fact, in some cases, combining the technologies can prove detrimental. “It has been shown that combining, for example, Ka- and Ku-band antennas can lead to non-optimal solutions for both systems,” he said. “Weight, size, reliability and performance can all be compromised by this approach, (and the) cost of certification is (also) big issue, which (in turn) drives the re-use of non-optimal already certified components.”

With a few exceptions, such as Ka, industry is largely reporting product and service costs are coming down as market for the services grows. In fact, “in terms of cost per bit, the cost of Global Xpress equipment is much lower than Inmarsat’s traditional L-band equipment,” Hnatiw said. “In absolute dollars, I expect the costs for the equipment to be comparable.”

“In spite of increased complexity, we are seeing a reduction in costs of L-band antennas due to higher levels of integration of features and production volume increases due to market take up,” Cahill said. “Cost of services (voice and data) has also been (falling); however, operators are still expecting (to present a) positive business case” although it might be difficult at this point. The use of these services “is, however, growing and will produce cost benefits to the operators as applications increase.”

The growth in use of the services is providing lift for sales in this market segment. “Our order book is full, and there are several … big customers that have not decided yet,” said Hill.

“The forward-fit market for broadband systems is strong,” said Hnatiw. “Most operators are choosing to equip their aircraft with broadband-capable antenna systems regardless of whether or not they have an immediate requirement for broadband,” he said. “Some operators are simply future proofing their aircraft.”

There has also been an upswing in the retrofit market, he said.

“In many airlines, forward-fit strategies are implemented and expanded into retrofitting the balance of the fleet once the overall cabin upgrade is defined and approved,” said Cahill. “The most robust segment is the long-haul aircraft where safety services set the requirement for aircraft connectivity,” he said. “Once on the aircraft, SwiftBroadband becomes a natural growth path for cabin and operational applications.”

Virgin Atlantic last November tapped Cobham’s HGA-7001 satcom high gain antenna subsystem to retrofit on seven of its Boeing 747s as part of its s Boeing 747 cabin upgrade program. The antenna will enable SwiftBroadband connectivity in the cockpit and cabin. The HGA-7001 satcom antenna sub-system has been selected for use on more than 20 airlines.

“There are a lot of commercial planes out there, and only a small percentage of them have this WiFi connectivity, so there is a huge market (opportunity),” said Tecom’s Chandra. For now, there is a competition to get the rest outfitted pitting providers using a satellite solutions versus the ground to air … (at this point) there is no clear winner.”

As far as technology developments are concerned, “we continue to refine (our) antenna … and are kind of waiting for the next quantum leap which will be the electrically steered phased arrays,” said Hill. “Boeing developed that technology maybe 10 years ago, but (the key is) making (it) economical” and capable of working north into Canada or south near the equator.

Cahill said he could see the “applications maximizing the use of current L-band technologies, particularly in aircraft operational applications, such as electronic flight bags, aircraft systems monitoring and reporting.” Also, the systems are likely to provide “rerouting and weather updates (that) should result in considerable fuel savings, and finally, carriers will “move to Ka-band for some cabin applications where larger bandwidth might be required.”

Offering a caveat, Hnatiw said: “This is a cautious industry when it comes to deploying new technology. Many enthusiastic airlines have been burnt by being too far on the bleeding edge, and those antenna solutions that are engineered specifically for the aeronautical market that combine simplicity with innovation will be much easier to deploy.”

Those “exotic antenna technologies (phased array antennas for example) in Ka-band may look and sound great in a PowerPoint presentation, but they are far too expensive, have significant performance tradeoffs and have unproven reliability.”

Next month: Lighting

Avionics Magazine’s Product Focus is a monthly feature that examines some of the latest trends in different market segments of the avionics industry. It does not represent a comprehensive survey of all companies and products in these markets. Avionics Product Focus Editor Ed McKenna can be contacted at [email protected].

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