Vacuum-Seal Waveguide Feedthrough for Extended W-Band 67–116 GHz

This article describes the design and performance of a vacuum-seal waveguide feedthrough with ultrawide RF band 67–116 GHz. We describe first the initial drivers behind the chosen design, then we present the results of the numerical simulations and optimization and provide thereafter the results of the RF and vacuum tests of the fabricated devices. The demonstrated RF performance is very close to the one expected from the simulation with an insertion loss less than 0.3 dB and a return loss better than 20 dB. Simultaneously, the feedthrough shows excellent vacuum isolation, Helium gas leak rate of < 2x10
⁻⁸
mbar·L/s is demonstrated, which allows using such a device in various space and ground applications.