ALMA Memo 381 Elements for E-Plane Split-Block Waveguide Circuits

E-plane split-block waveguide construction is well suited to many millimeter-wave components, including power dividers, frequency multipliers, and single-ended, balanced and sideband-separating mixers [1]. Recent ALMA memos have described quadrature hybrids [2] and a matched power divider [3] suitable for split-block construction. This memo describes four additional waveguide elements which can be used as building blocks in more complex circuits: a compact H-plane bend, a short E-plane bend, a matched E-plane Y-junction, and a broadband transducer from full-height waveguide to quartz suspended stripline. The components are suitable for fabrication on a CNC milling machine using an end-mill of diameter equal to the waveguide height, and do not require the insertion of separate waveguide short-circuit pieces at the ends of waveguides. Prototype designs are given for WR-10 waveguide (75-110 GHz), which can be scaled for any other waveguide size with the same 2:1 aspect ratio.