Design and development of RF window for high power Gyrotron

This paper describes design and development of single disc RF window for high power Gyrotron. The electrical design of edge cooled single-disc alumina window for 170 GHz, 1MW short pulse Gyrotron has been carried out using CST microwave studio. A diameter and thickness of the ceramic window are 90 mm and 3.16 mm, respectively, whose edge is directly cooled by water. The return loss (S11) and insertion loss (S
₂₁
) of 170 GHz Gyrotron window have been obtained as - 47.5 dB and - 0.02 dB respectively. In this paper thermal analysis of RF window has also been carried out using ANSYS software. The disc center and disc edge temperature has been found as 385 K and 288 K, respectively. For the sake of experimental validation, a highly purity (99.5%) alumina window based upon design has been developed and cold characterization has also been carried out using Vector Network Analyzer (VNA).