Development of Millimeter-Band Folded-Waveguide Slow-Wave Structures for a High-Power Traveling-Wave Tube Amplifier

Folded waveguide (FW) is a promising type of slow-wave structure (SWS) for millimeter-wave traveling-wave tubes. In this paper, results of development of millimeter-band FW SWSs are presented. SWS circuits are fabricated by CNC-machining. Cold electromagnetic parameters of the SWS are measured and reasonable agreement with the results of simulations is observed. Small-signal and large-signal gain are calculated.