Coaxial Beam Rotating HPM Mode Converter Using Dielectrics Plates

Abstract

The incorporation of the dielectric plates to produce phase delay for propagating waves is a widely employed technique in phase shifters and mode converters. In this article, a compact dielectric plate loaded coaxial beam rotating (CBR) mode converter having high gain and co-polarized (CP) pattern has been proposed for high-power microwave (HPM) applications at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${X}$ </tex-math></inline-formula> -band. Here, the input transverse magnetic (TM), i.e., TM01 mode, is converted to CP transverse electric (TE), i.e., TE11 likeness mode. The proposed design consists of a circular waveguide (WG) loaded with 12 dielectric polytetrafluoroethylene (PTFE) plates in a radial-azimuthal direction. For 5-mm plate thickness, the proposed design yielded a reflection loss of −20.01 dB with a radiation efficiency of 98.34% and a 17.9 dB gain at 10.084 GHz. Also, the power handling capacity of the proposed structure is predicted as 3.20 GW. Furthermore, the mode conversion is verified by measuring the far-field radiation pattern. Besides, the simulation studies of the thermal behavior of the proposed design are also discussed with the aid of CST Studio Suite.