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The Quest for the Ultimate Vacuum Tube

The cold-cathode traveling-wave tube, an ultracompact, ultraefficient source of RF waves, may finally be within reach

13 min read
The Quest for the Ultimate Vacuum Tube
Tubes in Space: The cold-cathode traveling-wave tube would make it possible to equip even very small communication satellites with powerful RF transmitters.
Photo: Sue Tallon

In July 1962, the Telstar 1 satellite took an enormous leap toward the globally connected world we now take for granted. It relayed from space, for the first time ever, live television images and telephone calls between continents: specifically, a ground station in Andover, Maine, and other stations in England and France. It accomplished this feat thanks to a microwave repeater that had at its heart a slight but powerful vacuum device known as a traveling-wave tube. The 30-centimeter-long, glass-walled electron tube was at the time the only device capable of boosting a broadband television signal with enough power to cross an ocean. Solid-state devices just weren’t up to the task.

More than a half century later, traveling-wave-tube amplifiers still dominate satellite communication. That’s right—your ultrahigh-definition satellite TV and satellite radio come to you courtesy of vacuum tubes in space.

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Deep Learning Gets a Boost From New Reconfigurable Processor

The ReAAP processor allows AI to be faster, more efficient

2 min read
different colored beams of light shooting up
iStock

This article is part of our exclusive IEEE Journal Watch series in partnership with IEEE Xplore.

Deep learning is a critical computing approach that is pushing the boundaries of technology – crunching immense amounts of data and uncovering subtle patterns that humans could never discern on their own. But for optimal performance, deep learning algorithms need to be supported with the right software compiler and hardware combinations. In particular, reconfigurable processors, which allow for flexible use of hardware resources for computing as needed, are key.

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Rory Cooper’s Wheelchair Tech Makes the World More Accessible

He has introduced customized controls and builds wheelchairs for rough terrain

6 min read
portrait of a man in a navy blue polo with greenery in the background
Abigail Albright

For more than 25 years, Rory Cooper has been developing technology to improve the lives of people with disabilities.

Cooper began his work after a spinal cord injury in 1980 left him paralyzed from the waist down. First he modified the back brace he was required to wear. He then turned to building a better wheelchair and came up with an electric-powered version that helped its user stand up. He eventually discovered biomedical engineering and was inspired to focus his career on developing assistive technology. His inventions have helped countless wheelchair users get around with more ease and comfort.

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Fourth Generation Digitizers With Easy-to-Use API

Learn about the latest generation high-performance data acquisition boards from Teledyne

1 min read

In this webinar, we explain the design principles and operation of our fourth-generation digitizers with a focus on the application programming interface (API).

Register now for this free webinar!

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