Design and Evaluation of Broad-Band High Pass Filter of Metal Perforated Sheets for Microwave Diagnostics

摘要

This paper reports characteristic evaluations of perforated metal sheet type high pass filters for milli- or microwave by numerical analysis and the guiding principle of designing broad-band high pass filters. The broad-band filters will be used for the microwave plasma diagnostics such as ECE, interferometer and reflectometer. We used 3D-modeling electromagnetic field calculation code to take complex interferences into account. The validity of the numerical analysis is guaranteed by a good agreement between calculated results and measured results. It is found that the frequency characteristic over the cut-off frequency depends on the filter thickness and that a thin filter is desirable for the ideal broad-band frequency filter.