A Compact TM01-TE11 Mode Converter Designed with Octagon Printed Periodic Substrates

Abstract

A compact TM01-TE11 mode converter designed with periodic substrates is presented in this paper. On each substrate an octagonal shape is printed on input side, of which the sides are connected with rectangular strips placed at an angle of 45⁰. Dielectric substrate FR4 (with εr = 4.4 and 0.025 loss tangent) is chosen for the proposed design. The fractional bandwidth of 4.92% (2.95 - 3.1 GHz) and maximum conversion efficiency up to 98.1% is achieved at the operating frequency of 3.05 GHz. Mode conversion efficiency is more than 90% over a bandwidth of 150 MHz at the operating frequency. The compact size and light weight of the proposed mode converter makes it suitable for airborne and portable High Power Microwave applications.