A waveguide cavity 180° hybrid coupler with coaxial ports

We describe the design, construction, and performance of a 180° hybrid coupler for the frequency band 1.3–1.8 GHz (L-band). The hybrid utilizes a WR650 rectangular waveguide cavity and has three 50 Ω coaxial ports. The signals are coupled in and out of the cavity through broadband coaxial probes attached to 7/16-type connectors. The measured performances are in excellent agreement with the electromagnetic simulations. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1646–1649, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24411