Investigation on a Ka Band Diamond-Supported Meander-Line SWS

Abstract

The microstrip meander-line traveling wave tube (TWT) is a kind of small sized, low voltage, low cost, and easy to fabricate TWT. It is an attractive choice for many applications, such as communication systems, phased array radars, security detectors, and electronic counter measure (ECM) instruments. In this paper, a Ka band U-shape meander-line slow wave structure (SWS) supported by a diamond rod is presented. The dispersion characteristics of this meander-line SWS are analyzed using CST MW Studio. The S-parameter simulation results show that the reflection is below − 15 dB between 32 and 38 GHz, and the particle-in-cell (PIC) simulation reveals that this meander-line TWT can produce 57 W output power at 36 GHz, when it is driven by a 8.1 kV, 0.04 A sheet beam with rectangular cross-sectional area of 1.0 mm × 0.12 mm. This meander-line SWS is manufactured, assembled, and tested. The good agreement between the simulated and measured S11 has been achieved and the mismatch between the simulated and measured S21 has been discussed at the end.