Waveguide and ridge waveguide T-junctions for wide band applications

Scattering parameters of waveguide and ridge waveguide stepped T-junctions are obtained using an extension of the three plane mode matching method. An optimization process is used to find the T-junction and step dimensions that yield a low reflection coefficient in one of the T-junction arms over a wide frequency band. The optimized wideband T-junctions are useful in the design of wideband high power dividers, diplexers and multiplexers. A wideband 3-dB T-junction was optimized and verified by measurement. The optimization model for the wideband diplexer was implemented. Using this model, a C-band T-junction waveguide diplexer with total 31% bandwidth and return loss better than 22 dB in pass bands was designed.<>