Millimeter-wave folded waveguide TWT development at Northrop Grumman

Summary form only given. A viable manufacturing technology to fabricate rugged, wide band millimeter wave circuits for Traveling Wave Tubes (TWTs) was developed and fully demonstrated. A simple and effective method of obtaining circuit attenuation is inherent to the technology. Eight devices operating over the instantaneous 40 to 55 GHz frequency band have been fabricated and successfully tested. Test results to be discussed include more than 100 W output power over the 40 to 50 GHz band, with unsaturated power levels of 50 W at 55 GHz, 180 W at mid-band, 135 W average power, 30 dB gain. Reproducibility of device fabrication will also be discussed. The applicability of the technology in the 80-to-110-GHz frequency range has now been demonstrated by successfully fabricating and testing for the first time ever a full gain circuit with graphite attenuator.