High Power Space TWT Successfully Demonstrates Record Power Levels

By: Emily Groh

Glenn, JPL (mission lead center), and L3 Communications Electron Technologies are pushing the limits on efficiently transmitting more data to the ground for NASA's space exploration missions. In May, L3 Communications successfully completed performance testing of the high power, high efficiency Ka-Band space traveling wave tube (TWT) at 180 watts through a 3-year project within Glenn's Exploration Systems Division.

The completion of this milestone marks the highest power space TWT manufacturing and testing ever conducted. The team is also developing and testing power combiner technology to obtain even higher power output and efficiency rates by combining two TWT devices. NASA's advances in TWT technology will improve the speed and efficiency of data communications enabling real-time, high resolution video transmission from space

Although the high power TWT is only the size of a loaf of bread, it is 18 times more powerful than the current state-of-the-art Cassini TWT, which has been orbiting Saturn since last July. The device is attractive for space applications since its radiation-tolerant materials can withstand the harsh conditions of deep space without the additional shielding required for a solid-state power amplifier (SSPA).

The high power TWT has successfully demonstrated a 50% increase in power efficiency and 100% more data bandwidth. These results translate into higher data transmission rates from greater distances, more flexibility, and more channels available for space communications.

Glenn has over two decades of experience in TWT modeling and design, which are critical components to the project. Commenting on how high power TWTs align with the Vision for Space Exploration, Technology Manager Irene Bibyk said, “It enhances the science data rate return for exploration missions by a factor of 10 and enables deeper, more sophisticated exploration of the solar system.” This work will result in a flight-qualified model used to design spacecraft for future deep space missions.