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11.09.2003

Communications: Harold Rosen

The Seer of Geostationary Satellites

by Jack McClintock

In the bedroom of his house in a canyon above Santa Monica, Harold Rosen switches on the high-definition television set. The face of Tom Hanks, who happens to live a few blocks away, fills the five-foot-wide screen, bounced straight from an orbiting satellite to Rosen’s dish antenna poised outside among the hummingbirds and flowers. “I get hundreds of channels for under a dollar a channel,” Rosen says with a grin. 

So do millions of others, and they have Rosen to thank for making that possible—and a lot more. It’s easy to forget how miraculous satellite-relayed television would have seemed just a few decades ago. Rosen recalls watching the Tokyo Olympics, the first continuous broadcast by geostationary satellite, relayed live in black and white in 1964. “I was amazed at how good the picture was,” he says. Today when he clicks his remote, channel after channel from around the world appears on the screen: news, talk, politics, science, nature films, and sports.

Rosen, 77, remembers well, because he led the team that invented the first geostationary communications satellite.




Photograph by Amanda Friedman

If Harold Rosen’s team hadn’t figured out how to send satellites to circle Earth in controlled, equatorial orbits, today we’d have no live transmission of the Olympic Games, no satellite phones in Iraq, no faxing to Hong Kong.

The idea for a space-based communications satellite network was first suggested in 1945 by writer Arthur C. Clarke. Many scientists had dismissed Clarke’s proposal as far-fetched. But when the Soviet Union launched Sputnik in 1957, the world looked up and saw that the future of communications hung in space. Rosen and a handful of others would put it there by hurling voice, television, facsimile, and data communication around the world.

Rosen was working at Hughes Aircraft, developing radar systems, when Sputnik went up. Soon he became manager of satellite development. Global communications were still primitive. In 1960 a maximum of 136 Americans could talk to Europe at one time-100 on high-frequency radios and 36 via AT&T’s year-old transatlantic submarine cable. Transatlantic TV didn’t exist. Rosen saw an opening.

Not many did, because the obstacles were enormous. At AT&T’s Bell Laboratories, John Pierce—a scientist “so important he named the transistor the transistor,” Rosen says respectfully—had proposed a fleet of low-altitude communications satellites. In 1960 Pierce persuaded NASA to fund the Echo balloon satellite. Radio waves were transmitted from one ground station to another by bouncing off the aluminum-faced 100-foot-diameter Mylar balloon.

But without amplification, the signals weakened over distance. Telstar 1, a more sophisticated device that amplified and re-sent signals, followed two years later. But the low-flying Telstar didn’t stay in one place, so it could be used only for short periods at a time, and gigantic swiveling ground antennas required complicated electronics to keep them pointed toward the satellite as it passed overhead. The complexity and expense made it difficult for competitors to challenge Bell, then the only telephone company in the United States. Bell, Rosen says, was happy with its monopoly, which the company assumed it would be able to count on as communications became international. However, “a geostationary satellite is much more democratic,” Rosen says, because it’s simpler and cheaper.

His team set out to position a satellite high in space and get it circling Earth’s equator at precisely the right speed to stay above a particular point on the ground, thus making it geostationary. Radio waves bounced to and from that satellite, orbiting at 22,238 miles above Earth, could reach nearly a third of the globe. Rosen thought he could design a small satellite with sufficient bandwidth for television transmission or 100 telephone channels and build it in a year for $5 million. He consulted with fellow engineers Tom Hudspeth, John Mendel, and Donald Williams, and they agreed. Rosen thought it would be very profitable. “Being bold, I said we could probably sell an hour a day of television,” he laughs. “The head of the communications division thought an hour a week would be a lot.” He waves at Tom Hanks on the TV screen.

 



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