A three-frequency feed for millimeter wave radiometry

A high-performance millimeter-wave feed, designed for a broad-band radiometry application is presented. The feed provides three separate output ports in the 87-97 GHz, 125-135 GHz, and 161-183 GHz bands. Measured return loss is better than 20 dB in the upper two bands and 15 dB in the lowest band, and good pattern symmetry is obtained throughout all three frequency bands. V C 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2483-2487, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27118