Optics Rotation Project of Douglas Bennett
Advisor: Dr. Peter Koch and Kevin Schultz
Title: Continuously Tunable Bandpass Filter
Continuously Tunable Bandpass Filter
My goal for this rotation was to build a continuously tunable direct-coupled-cavity bandpass filter based upon the design of a similar filter described in an Direct-coupled-cavity bandpass filters using scrounged rectangular-to-circular waveguide transitions by S. A. Zelazny and P. M. Koch [1]. The filter design discussed in this article can be built quickly and cheaply using parts that can be fabricated in a machine shop and parts scrounged from other equipment. The waveguide bandpass filters (WGBP) consist of thin, metallic irises mounted inside a waveguide. The irises form cavities that can be made to resonate at the center of the desired pass band. The design in the article consisted of two cylindrical cavities that share a common iris (directly-coupled). The length of the cavity was chosen so that the desired TE mode resonates at the desired frequency. My project consisted of attempting to replace the circular waveguide used for the cavities with a flexible bellows, so that the length could be continuously tuned by contracting or expanding the bellows.
Resonance in a Cylindrical Cavity
Douglas Bennett
Douglas.Bennett@sunysb.edu