Extremely Wide-Band Ridge Waveguide Radial Combiners

This paper presents a novel configuration for an extremely wide-band five-way non-resonant ridge waveguide radial combiner. The combiner exhibits better than 90% combining efficiency over a 125 % fractional bandwidth while occupying a very compact volume. The proposed design promises to be useful in wide-band high power applications. The methodology to design the radial combiner is presented. It starts with designing the individual ridge waveguide input ports, then designing a transformer section that provides matching between the individual ridge waveguide ports and the common coaxial line output port. Proper design of the different cross sections makes it possible to achieve the required impedance levels for good matching across an extremely wide bandwidth. A proof of concept prototype is designed, simulated, fabricated and tested demonstrating excellent measured results without any tuning.