Non-reciprocal mode-converting substrate integrated waveguide

In this paper, we propose and demonstrate a fundamental approach to developing a fully integrated structure called non-reciprocal mode-converting waveguide (NRMCW). This is a ferrite-based device, where TE10 mode is converted into TE20 mode in one direction, but it is preserved in the reverse direction. In other words, the mode conversion happens only in one direction. Further, to demonstrate one application of such a device, a new type of circulator is designed and fabricated on the basis of substrate integrated waveguide (SIW). Theoretical and experimental results are presented to validate the whole new concept and foundation work.