W-band wideband low loss planar integrated circuit diplexer

This paper describes the design and performance of a contiguous 90 to 112 GHz diplexer using the integrated finline technique. Insertion losses of 1.5 dB have been achieved. There is good agreement between the experimental results and those predicted theoretically; these results demonstrate a significant technological advance of mm-wave multiplexers using printed circuit techniques. Results of an extremely wideband H-plane tee with an SWR of less than 1.4 over the full W band (75 to 100 GHz) also are presented.