Hughes Electron Dynamics

Hughes Electron Dynamics is a world leader in the design and manufacture of microwave, traveling wavetube amplifiers, and ion thrusters for commercial and military applications.

Making Waves

Traveling wave tube amplifiers (TWTA) are the most expensive components of satellites and the heart of their communication capability. That's why the vast majority of U.S. government spacecraft and 70% of the world's commercial geosynchronous communications satellites currently in orbit use reliable Hughes TWTAs. Their job is amplification at microwave frequencies (above 500 MHz). RF ground signals are very weak by the time they reach a spacecraft in orbit. TWTAs boost the ground signal power thousands of times, then relay the amplified signal back to Earth. Nothing else matches TWTs' combination of high bandwidth, power output, and gain. The heart of the DoD's Defense Satellite Communications System (DSCS) Service Life Enhancement Program (SLEP) is the set of unique, custom-manufactured 50-watt Hughes TWTAs that make SLEP possible. For more than 30 years, Hughes Electron Dynamics has designed and built unmatched space TWTAs to meet commercial and more stringent government needs, accruing more than 231 million operating hours in orbit with projected reliability of 340 years between failures.

Another technology Hughes employs to generate and amplify microwaves is solid state power amplifiers (SSPA). These devices combine the power from many transistors. Their compactness (2 inches long, vs. about 2 feet for TWTAs) makes them ideal for multibeam applications, which require hundreds or even thousands of transmit elements. Long favored for low-power, low-frequency applications, SSPAs are becoming ever more competitive with TWTAs.

Power to Burn

How do you make spacecraft propulsion ten times more efficient? Hughes does it with a xenon ion propulsion system, called XIPS. Instead of burning chemical fuel like most current satellites, XIPS accelerates positive ions of xenon gas through a thruster to a speed of 62,900 mph (30 km/sec). The culmination of four decades of research, XIPS reduces fuel needs by up to 90% for a satellite with a 12- to 15-year operating life. Less fuel means lower launch costs, an increase in payload or lifetime, or any combination of these choices.

First flown on an HS 601HP spacecraft for PanAmSat, XIPS generates a smooth, steady thrust that is proving ideal for accurate station-keeping, and can perform orbit raising for Hughes' HS 702 satellite models. Our ion propulsion has also performed brilliantly on NASA's cutting-edge Deep Space 1 mission.