In the early 1990s, Peter Rossiter of SkyWave Mobile Communications approached CRC's Michel Cuhaci, Manager of the Advanced Antenna Technology Research group, with the specifications for a new antenna his company wanted the lab to design. Specifications, Cuhaci remembers, that he knew would be difficult to achieve.

The small start-up company was designing a mobile satellite terminal for asset management. Their terminals, they hoped, would be placed on trucks, train cars, containers, even ships at sea, and allow fleet managers to pinpoint not only the location of that asset, but a whole host of other factors including speed and direction of travel, engine condition, cargo temperature, even what door locks had been accessed. In short, a range of parameters tied to the state and security of the vehicle and cargo. For the system to work, however, they needed an antenna that would be small enough to fit within the terminal - about the size and shape of a small smoke alarm - that would sit inconspicuously on top of the asset. But, despite its small size and flat shape, the antenna would require the power and sensitivity to communicate with a satellite 36,000 km above the equator. The final requirement was that the antenna cost less than three dollars a unit to produce.

An antenna, explains Cuhaci, is a transducer. It takes one form of energy and transforms it into another. Antennas can both radiate (transmit) and receive signals. On the transmitter side, the antenna takes an electrical signal fed to it and transforms that signal into an electromagnetic wave - the backbone of wireless communication. On the receiving end the process is reversed, with the antenna capturing the electromagnetic wave carrying the signal and transforming it into electrical energy which can then be deciphered and processed by electronics and software.

While Cuhaci knew that SkyWave's specifications would be a challenge to achieve, he was also confident that the lab had the tools and expertise to succeed. Not only was his group the largest independent antenna research group in Canada, they boasted cutting-edge facilities for modelling, prototyping and characterizing antennas. Even more important, says Cuhaci, the lab consistently follows a two-pronged approach to research, working with clients to develop prototype antennas for their specific - and often extremely challenging - applications, while at the same time maintaining a strong program of forward thinking, visionary research.

"The work we're doing with clients today is based on research we did 10 years ago," explains Cuhaci. "We have to be ahead of the game so we have the right tools, the right technologies, when the client arrives with a new application. Otherwise it's too late."

Faced with SkyWave's exacting specifications, Cuhaci's lab started by doing sophisticated modelling of the electromagnetic characteristics of possible antenna configurations. They looked at a range of possibilities, including different styles of microstrip patches, different feeds to the antenna and different antenna materials.

According to Rossiter, this shaved both time and money off the development process. "We were able to look at half a dozen configurations over a period of weeks," says Rossiter, "and predict their performance very accurately without the high cost of building and testing multiple prototypes."

Once Cuhaci and Rossiter had flagged configurations of interest, CRC's model shop built prototype antennas based on those designs. The prototypes were then tested and characterized in specialized electromagnetic-anechoic chambers, and promising candidates tweaked and retested to optimize their performance. "Through CRC we had access to test chambers, to automated network analyzers, to calibrated test antennas. With all this, we were able to form very accurate and repeatable measurements on prototype antennas."

CRC’s state-of-the-art antenna test facilities today.

So accurate and repeatable, says Rossiter, that when SkyWave Mobile presented the results to INMARSAT - the satellite network consortium that SkyWave hoped would carry their signals - their terminal passed INMARSAT's stringent requirements on the first try. "Within 13 months of going to CRC we had a fully developed terminal and antenna, and INMARSAT granted us type approval."

SkyWave is now a world leader in satellite-based mobile asset tracking systems, with over 100,000 users worldwide, $50 million in cumulative sales over the past 10 years, and a bright future ahead. A future, says Rossiter, very much tied to antenna design.

"In the next five to ten years, we're going to be looking at smaller and smaller beams, frequency re-use just like we see in cellular systems, and we're going to need more intelligent, adaptive antennas: beam formers, interference cancelling. And all of this has to be done at a ridiculously low price point," says Rossiter.

Not surprisingly, Cuhaci's lab is focussing its long-term research efforts on precisely these types of projects. For example, says Cuhaci, his group is developing antenna designs for frequency bands that are currently not being used but, given the current overcrowding of the electromagnetic spectrum, will open up in 10 to 15 years. These high-frequency bands will likely support a new generation of medical devices for diagnosis and treatment, as well as finding use in screening and security devices. But for these applications to become a reality, he stresses, they will require antennas that can reliably send and receive information in these higher frequencies.

The lab is also working on the kind of antenna Rossiter predicts will be needed in his particular business - antennas with internal complexity able to change frequencies and orient to maximize signal strength. And, Cuhaci adds, the lab is always looking at new materials and innovative designs that will make the antennas of the future "industry friendly." One example is a project to develop flat satellite dishes. A simple change in shape - as long as performance is maintained or improved - would make the antennas easy to pack, transport and assemble.

"We're also looking at technologies for producing antennas in ways people can afford," he explains. "If you're talking about an antenna going into any consumer product, that's a big constraint." For example, the lab is investigating ways to print antennas using an ink-jet printer. "It's being done for low-cost solar cells using polymers and nano-materials printed on plastic, so maybe we can use it here."

Cutting-edge antenna design and performance, says SkyWave's Rossiter, is integral to the success of a company like his. "The antenna is where the fundamental performance of the terminal is established, to a large extent. It's where the real advantages can be had. The signal processing has to be done very rigorously in the DSP [digital signal processing] portion of the terminal, but the antenna is where the battle is fundamentally won or lost."

For more information, please contact Michel Cuhaci, Manager of the Advanced Antenna Technology Research group, at michel.cuhaci@crc.gc.ca or 613-998-2548.

On June 18, 2009, CRC and SkyWave Mobile Communications Inc. received a technology transfer award from the Federal Partners in Technology Transfer (FPTT). Skywave began with four engineers when it first joined CRC’s Innovation Centre in 1997. Now a world leader in telematics products and services, it has 80 people with $50 million in cumulative sales over the last 10 years.
Back row, left to right: Michel Cuhaci (CRC), Peter Rossiter (SkyWave), Vadim Volinski (SkyWave); front row, left to right: Aldo Petosa (CRC), Nicolas Gagnon (CRC) and Doug Reveler (SkyWave).