ADVANCED INNOVATION DETECTED
29 September 2017
The 2017 Saab Innovation Prize has gone to Dr. Henrik Holter for his invention of a new phased array antenna, which is central to the electronic warfare system of Gripen E.
“My invention is a wideband phased array antenna aperture for modern AESA systems,” says Henrik.
“The antenna aperture was especially developed for wideband electronic warfare systems. You can control the shape of the antenna beam by controlling the amplitude and phase of each antenna element and you can also both transmit and receive signals. It can also be used for wideband radar systems.”
The efficiency of the phased array system
Henrik’s antenna has not one antenna element but a full array of antennas. This means that the phased array system can simultaneously and independently track different targets. The system can also track targets independently of search volumes. Compared with traditional mechanical antenna systems it gives the pilot an enviable tactical advantage.
Although phased arrays are not new, they’ve existed since Second World War, they have had performance issues and have been expensive to manufacture. Despite this they have always had qualities much in demand; they are difficult to jam and have a lower probability of interception. Ultimately it is the speed with which the antenna beam can be scanned across a wide area for which they are most valued.
Solving the problem of cost
There are actually very few types of wide band phased array antennas on the market. Henrik‘s main challenge was to reduce cost using modern technology. Henrik estimates that compared with the earlier technology, his system is around 60% cheaper to make.
“In earlier technology the antennas were connected to each other, but with this one the antenna elements are not connected, which means that there are separate pieces, which is a real advantage when you put it together.” With several such antennas on each Gripen aircraft and a lot of Gripens being manufactured, this cost saving is very welcome.
Although Henrik claims that the main significance of his new antenna is its lower manufacturing cost Pontus de Laval, Saab’s CTO, disagrees saying Henrik is too modest. “I have never seen anything as good,” says de Laval. “Lots of people around the world view these antennas as key components and have spent millions to develop them. But Henrik has found very innovative solutions to this problem. And as well as being cheaper to make, the way he has actually made the antenna element in this array is quite unique. It is more effective.”
Antennas — a curiosity turned into a career
While serving his national service as a young naval officer Henrik first became interested in radar systems. “I served on surface attack ships and became a technical officer working with radars and communications.” His curiosity led him to study and then to teach. For his Masters of Science he specialised in electro physics and was named the best graduate of the year at Stockholm’s Royal Institute of Technology (KTH), and its school of electrical engineering. He then undertook his PhD in electromagnetic field theory, also at KTH. This included a six-month posting to the Antenna Laboratory at the University of Massachusetts.
After finishing his PhD, Henrik became an Assistant Professor at KTH.
“It’s hard to say how I became interested in antennas,” Henrik says. “Antennas are a combination of theoretical and practical things and I found the combination interesting.”
Henrik has published around 40 papers within the antenna area. In 2001 he began developing phased array antennas and other antennas for Saab. To say Henrik is an expert in the antenna technology field would be an understatement.
After 12 years of research at Saab, Henrik became the manager for antenna and microwave development, and more recently the Head of Research & Technology at Saab’s electronic warfare division.
Henrik’s antenna is now being developed for use on other systems, beyond the Gripen.
Saab’s investment in innovators
“Saab spends 25% of its revenue on R&D. That’s a lot compared with other companies,” reflects Henrik. “People in the company can apply for patents if they have an idea. I have five myself, including one for this new antenna. If you submit an innovation it’s rewarded. Inventions are really important for Saab. It’s the reason why we exist,” he concludes.
Just the facts...
Name: Doctor Henrik Holter
Position: Head of Research & Technology, SAAB Surveillance, Electronic Warfare, Järfälla
Education: Master of Science in Electro Physics and PhD in Electromagnetic Field Theory, KTH
Career: Technical Officer in the Navy, Assistant Professor at KTH, Antenna and Microwave researcher at SAAB, Manager of Antenna and Microwave Development at SAAB
Hobbies: Mountain biking, kayaking, machine learning
Family: Wife Anne and 14-year-old daughter
