Application of band-stop filters for the 30-200 GHz range in oversized microwave systems

A simple and cheap method has been developed to prepare band-stop filters for the frequency region 30-200 GHz with a typical attenuation in the stop band of more than 27 dB. This filter consists of periodic metallic structures deposited on a thin substrate. The preparation is achieved by applying a commonly used chemical etching technique on a commercially available thin print board. These so called "capacitive meshes" are applied successfully at the Rijnhuizen Tokamak Project for protection of a microwave diagnostic against high power microwave input. (C) 1999 American Institute of Physics. [S0034-6748(99)00906-5].