Broadband left-handed rectangular waveguide using a shorted stub and twisted E-plane posts

Abstract

A broadband left-handed (LH) waveguide operating above the cutoff frequency is presented. The unit cell consists of one-shorted stub and two-twisted posts. The structure induces double loops in the surface currents, resulting in enhanced inductance which broadens the negative permeability region. To analyze the LH properties of the structure, a 2-port network cross-connected equivalent circuit is derived. The measured results of the LH waveguide constructed with five unit cells in an X-band are in good agreement with simulated data and show a good transmission property as well as a broad LH fractional bandwidth of 26.5%. (c) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:835840, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27419