Synthesis Method for Highly Oversized Serpentine Mode Converter

In this article, the method to design highly oversized circular TE
01
to TE
11
serpentine mode converter is proposed. The mode coupling in oversized elliptical waveguides is firstly analyzed, and their ability to suppressing the generation of parasitic modes is illustrated. For a high conversion efficiency and broad bandwidth, elliptical waveguides are introduced into the mode converters as the transmission structure. In order to validate the analysis, a highly oversized mode converter working in W band is designed and simulated. Results indicate that a relative bandwidth more than 20% with a conversion efficiency over 95% is achieved under the conversion length of 1.15 m.