Agilent Fellow Joel Dunsmore on art of test & measurement

"I had come across a really interesting technical phenomenon," he said. "Tuning filters for base stations and wireless was a big thing for test equipment. There would be hundreds of network analyzers with rows of people tuning filters. We were developing a new high-speed processor to make them faster. I had one channel that was doing high-speed filter tuning and the other for Fourier transforms. When I tuned the filter in the frequency domain, something weird was happening in the timing domain. I'd never noticed that before."

"I discovered you could tune filters in the time domain and faster than in the frequency domain," Dunsmore said. An Agilent consultant at the time turned out to be the dean of engineering at the University of Leeds, which is where Dunsmore ended up doing his Ph.D work.

"I said to him do you think that would be a good thesis topic? He said yes," Dunsmore recalled.
A few years later, Agilent elevated him to Fellow, where he continues wrestling to the ground the measurement problems of today.

Last foot challenge

"Clearly the biggest (test challenge) is the last foot from the test equipment to the device the customer is measuring," Dunsmore said. "It's that interface that causes worlds of difficulty. The last patent I applied for focused on that interface. You could measure a cell phone and there's no connector on cell phone, so you have to deal with a radiator into the phone. What about a wireless chip with optical link on one end and wireless link on the other and no place to connect?"

Separately, what about "a tiny little chip with bunch of connectors? Our customers want to test their chip as though nothing else was connected to it. That's the 'fixturing' problem," Dunsmore said.
And, like a relentless drumbeat, there's optimization and integration of each new generation of T&M equipment.

"Intelligent optimization is a really interesting area," Dunsmore said. "We'll need to control a lot more things and not test just one thing at a time."

The son of parents whose career was made with their hands has made his with his head, and, along the way, imparted some of that wisdom to college students, with teaching stints at U.C. Berkeley.

And, in an age of constant relocation, Dunsmore has stayed at the same company since his internship.
While HP was a big company, Agilent is a big company as well that affords him opportunities.

"When you move from job to job, it's like  moving from company to company," Dunsmore said. "I never felt like I was getting stuck in a spot where I was button-holed. I've done optical work, moved into microwave and then into wireless communications."

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