Optimization of novel high-power millimeter-wave TM/sub 01/-TE/sub 11/ mode converters

In this paper, a numerical study of direct TM/sub 01/-TE/sub 11/ mode converters in highly overmoded, bent smooth, circular waveguides is presented for high-power millimeter waves. The various shapes of bent waveguides are elaborately chosen, and their optimized geometrical dimensions have been achieved with a general optimization code employing the coupled mode theory. The mode converters designed can have high conversion efficiencies over 98% and wide bandwidths of 28%.