BANDWIDTH-ENHANCED METAMATERIAL ABSORBER USING ELECTRIC FIELD-DRIVEN LC RESONATOR FOR AIRBORNE RADAR APPLICATIONS

The aim of this article is to construct broadband ultra thin absorbers using metamaterials in microwave frequencies (C-band) for lower band surveillance and air defense applications. The frequencies of absorptions have been brought closer by parametric optimization of electric field driven LC structures to give rise to a higher full width at half maxima (FWHM) bandwidth. The FWHM bandwidth of 0.42 GHz with 8.13% has been theoretically observed ranging from 4.94-5.36 GHz. The structure is fabricated and experimentally tested for the normal incidence of electromagnetic wave inside the anechoic chamber. The structure is also investigated for oblique incidence which shows that FWHM bandwidth is maintained upto 40 degrees. The structure is also simulated for different angles of polarization where insignificant shift in frequency is noticed as well as FWHM bandwidth is also maintained upto 30 degrees. (c) 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2131-2137, 2013