Title :
Incident angle-dependent effective surface impedance (ZS) of Electromagnetic Crystal (EMXT)
Author :
Xin, Hao ; Kim, M. ; Hacker, J.B. ; Higgins, J.A.
Author_Institution :
Rockwell Sci. Co., Thousand Oaks, CA, USA
Abstract :
Electromagnetic crystal (EMXT) surfaces are modeled with effective surface impedance method. Effects of oblique incidence are studied using a technique similar to the waveguide simulator method for analyzing infinite phased array. Numerical results are compared with an analytical model. EMXT samples are characterized by open-ended waveguide reflection measurements using different aperture sizes (WR28 and WR22). The measurements confirm the angular dependence of the EMXT surface impedance. A rectangular waveguide with EMXT sidewalls is modeled by using the angle-dependent effective surface impedance as the sidewall boundary condition. Excellent agreement between this model and full-wave finite-element simulation of the entire waveguide structure is obtained.
Keywords :
electromagnetic wave reflection; finite element analysis; rectangular waveguides; surface electromagnetic waves; surface impedance; waveguide components; EMXT sidewalls; effective surface impedance; electromagnetic crystal; finite-element simulation; incident angle-dependent surface impedance; infinite phased array; oblique incidence; open-ended waveguide reflection; rectangular waveguide; sidewall boundary condition; waveguide simulator method; waveguide structure; Analytical models; Apertures; Electromagnetic measurements; Electromagnetic modeling; Electromagnetic reflection; Electromagnetic waveguides; Impedance measurement; Phased arrays; Size measurement; Surface impedance; EMXT; Electromagnetic crystal; infinite phased array; surface impedance; surfaces;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2004.832077
