Demonstration of A Compact W-Band Sheet Beam Traveling-Wave Tube

This letter reports the successful development and testing of a compact W-band sheet-beam traveling-wave tube (TWT) integrated with a periodically-cusped magnetic (PCM) focusing system. The prototype exhibits a compact form factor of 70 mm × 83 mm × 240 mm and a weight of less than 2.1 kg. Driven by a 25.5-kV, 141-mA elliptical electron beam, the amplifier delivers approximately 200 W of peak power at 94 GHz, with output power above 100 W across the frequency range of 89 – 100 GHz. Notably, the long-distance transmission of the sheet beam (over 120 mm) is realized with a measured transport current of 130 mA corresponding to 92% of the total beam current. This work lays a foundation for application of the sheet-beam TWT in miniaturized high-frequency microwave systems.