L-band travelling wave tubes amplifiers for navigation satellites

Summary form only given. Based on the upcoming needs in new navigation systems, Thales Electron Devices (TED) performed an upgrade program to extend the performance of its L-band TWT family. In the meantime, up to 250 W of output power can be provided by a single TWT, with efficiencies as high as 63% in saturated operation. The TWTs have been tested against all sensitive parameters and could so far support all modulations schemes, yielding very low values for group delay and group delay stability. To meet the linearity requirements, the tube can be operated either in backoff mode or in combination with a lineariser. This presentation shows the actual performance data of TED´s improved L-band tubes, and demonstrates through the obtained results that L-band TWTAs provide attractive solutions, suited for all navigation systems.