The Time of His Life

A Graziadio alumnus changes the world by launching time into space

October 24, 2019  | 4 min read

xxAs a child packed among other terrified German citizens in World War II’s Frankfurt bomb shelters, Hugo Fruehauf (MBA ’07, PKE 117) discovered that keeping occupied was a way to cope with a confusing, frightening world.

“They called me Beaver,” he says, “because I was always busy, building something with blocks or an erector set and taking things apart to see how they worked.”

This penchant for creating new things, and the horror of carpet- bombing—the wartime practice of bombarding an enemy’s civilian structures along with military targets—have stayed with Fruehauf throughout his life. He has used both passions to dramatically change the world.

Fruehauf is one of four recipients of the 2019 Queen Elizabeth Prize for Engineering for the creation of the Global Positioning System (GPS). Often referred to as the missing Nobel Prize for engineering, the prize is awarded to an individual or team whose groundbreaking innovation in engineering has had a global impact on humanity. Fruehauf’s contribution to the system was critical to its success.

For satellites to convey accurate positioning data, they must keep precision time, and the most precise timekeeping device known to man is the atomic clock. Fruehauf describes an atomic clock as one that “basically uses atoms as a pendulum.” By exciting the electrons circling the atoms’ centers, they are compelled to switch their magnetic dipoles, acting like a pendulum. The first atomic clock, “as big as a refrigerator,” was built in the 1930s, before Fruehauf moved to the US at age 13. By the 1960s, the devices were about the size of a microwave oven, but they were still far too large and heavy to send into orbit.

Hugo FruehaufFruehauf was then employed as an engineer with North American Rockwell. His knack for being in the right place at the right time, along with having exceptional circuit design skills, had given him the opportunity to become chief test conductor for the second stage of the Apollo, Saturn-V launch vehicle while only in his 20s. The following decade, the US military contracted with the renamed Rockwell International to create a satellite-based positioning system for all its secure needs. One of Fruehauf’s tasks in this effort—to miniaturize the clock such a system required—seemed impossible. When he learned of a German scientist, Ernst Jechart, living nearby in Southern California who had done exactly that, he didn’t believe it.

“It was almost as if God had designed it and had put me on its trail,” he says.

As a native German speaker with a knowledge of large atomic clocks, Fruehauf had the language skills to understand the inventor’s creation. With this four-by-four-by-four-inch clock as their prototype, Jechart and he set to work. They redesigned it for survival in orbit environments and thus created the first fully radiation-hardened, military atomic clock in space—a central feature of GPS technology.

For the first 20 years of their existence, GPS signals were fully operational for use by the military. During the first Gulf War, the military relied heavily on GPS receivers for navigation and for precision targeting of Iraqi forces. The open, unencrypted civil signal, however, was deliberately degraded to render it sufficiently inaccurate for terrorists to use in precision counterattacks. By 2000, President Clinton felt that the global benefit of the unencrypted signal outweighed fears of its abuse, and that year he gave the world access to a precise, open, commercial signal. As Fruehauf points out, this new navigation signal, coupled with advances in the cell phone industry, put GPS on the map.

“GPS receivers are now the size of the fingernail on your pinky, and they only cost two dollars,” he says. “This is what helped blow GPS into the world.” Today’s finely tuned GPS that instructs us what alternative route to use during a traffic jam relies on an open signal that is about as good as it can be. Jokingly, Fruehauf says, “We’re pretty much at the place where God keeps time.”

Fruehauf sees “endless uses” for the technology and it now touches us in myriad ways. We use it to locate lost hikers and to more quickly land planes at airports, and as Fruehauf hoped, it has eliminated the practice of carpet-bombing in military conflicts. It’s also been a boon to farmers. Fruehauf explains that “by using GPS as a tractor navigator, along with a small tower’s correction signals, a tractor can harvest or seed a field in tracts accurate to an inch. The result is a 10 to 20 percent higher land use and yield.”

Receiving the Queen Elizabeth Prize is a testament to the remarkable nature of the GPS inventors’ achievement, and there is no doubt that Fruehauf’s tenacious character played a role in it. “My claim to fame is that when I think something is possible, even if I don’t know how to do it, I go for it,” he says. Nonetheless, he is keenly aware of the almost divine serendipity at play in his life. “I was very much at the right place at the right time. There is some miraculous element about this that I enjoy more than the accolades I get.”


Along with three colleagues, alumnus Hugo Fruehauf received the 2019 Queen Elizabeth Prize for Engineering for his work on the American Global Positioning System.


GPS in Service

  • Predicts earthquakes by tracking tectonic plate movement

  • Guides humanitarian supplies into disaster relief zones

  • Helps the environment by locating plastic in the ocean

  • Finds and rescues ships in distress

  • Enables precision farming with satellite-guided tractors