Skip to Content
MIT News magazine

Charles C. Counselman III '64, SM '65, PhD '69

MIT professor emeritus advanced GPS technology
December 21, 2010

In 1979, Chuck Counselman gave an after-dinner speech at the International Union of Geodesy and Geophysics meeting in Canberra, Australia. The MIT professor used the opportunity to describe a little something he’d come up with: a way to measure, with millimeter-level accuracy, the position of one point on Earth with respect to another point hundreds of kilometers away. The audience reacted with stunned disbelief. “It was as if I’d told them that in my spare time, in the basement, I’d cured cancer,” Counselman says.

A chief NASA scientist stood up and labeled Counselman’s invention “snake oil.” Far from snake oil, however, it was a fresh way to harness the United States’ new Global Positioning System (GPS) satellites. Counselman had done it by combining his expertise in radio and astronomy.

Each GPS satellite broadcasts a signal that, like other radio signals, is generated by modulating, or varying, a “carrier” wave to convey information. Counselman was the first person to compare the carrier waves of these signals instead of the coded modulation of the waves. The carrier wavelength was so short—about 190 millimeters—that the resulting position uncertainty was smaller by a factor of 1,000 than what the Department of Defense and NASA were getting with the modulated waves. He also configured the receivers differently, winnowing multiple antennas and channels down to a single omnidirectional antenna and one channel so as to tune in to and read a composite signal from all the satellites in the sky. With fewer components, Counselman’s receivers were simpler, more compact, and cheaper to make. He called them MITES, for “miniature interferometer terminals for Earth surveying”—or “MIT engineering success,” he says. He proved his technology in a series of demonstrations in the early 1980s and was subsequently granted 36 patents.

Counselman earned his first two MIT degrees in electrical engineering and lived at Chi Phi as an undergraduate. “We did everything—hired the cook, bought the food, cleaned the house, upgraded the heating system,” he says. “It was good training for adult life.” He met his wife, Eleanor, at a Wellesley mixer; they have a son and a daughter.

Now a professor emeritus, he completed his aero/astro PhD and taught planetary science, astronomy, and electrical engineering at MIT until 2002. His economics minor has come in handy in chats at the tennis club, where he plays with Nobel laureates in economics.

Recently, he was exploring the Deutches Museum in Munich and saw one of his receivers in a huge glass display. “I just about fell over,” he says. “I didn’t even have my camera with me.” In 2008, the American Geophysical Union gave Counselman its Charles A. Whitten Medal for “outstanding achievements in research on the form and dynamics of the Earth and planets.” The organization noted that GPS receivers based on Counselman’s technology are ubiquitous, portable, and inexpensive.

Keep Reading

Most Popular

Russian servicemen take part in a military drills
Russian servicemen take part in a military drills

How a Russian cyberwar in Ukraine could ripple out globally

Soldiers and tanks may care about national borders. Cyber doesn't.

Death and Jeff Bezos
Death and Jeff Bezos

Meet Altos Labs, Silicon Valley’s latest wild bet on living forever

Funders of a deep-pocketed new "rejuvenation" startup are said to include Jeff Bezos and Yuri Milner.

conceptual illustration showing various women's faces being scanned
conceptual illustration showing various women's faces being scanned

A horrifying new AI app swaps women into porn videos with a click

Deepfake researchers have long feared the day this would arrive.

ai learning to multitask concept
ai learning to multitask concept

Meta’s new learning algorithm can teach AI to multi-task

The single technique for teaching neural networks multiple skills is a step towards general-purpose AI.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.