An innovative tunable and polarization-insensitive 1.6-8 GHz frequency selective surface (FSS) absorber was investigated in this study. The proposed FSS, which is in 4-axial symmetrical form, includes a novel array of PIN diodes with biasing lines including inductors. A gradually reduced equivalent resistor of PIN diodes can be achieved with increasing DC voltage, which characterizes tunable, m...

This paper presents a polarization insensitive frequency selective surface (FSS) based on concentric ring slots with five closely spaced passbands. The proposed FSS unit cell contains coupled supplementary innermost slot. close band response within the first transmission bands is achieved by influence of modified geometry obtained inclusion sixth added slot causes appearance stopband, due to co...

In this article, the working mechanism of a wideband absorber designed with an adjustable and highly selective notch band is studied, in which narrow independently controlled by lower lossless layer absorber, whereas upper lossy loaded lumped resistors realizes absorption. We present two instances geometrically electrically bands, respectively. Without decreasing absorption performance, positio...

Time-resolved fluorescence spectroscopy is used increasingly to probe molecular motions at the aqueous interfaces of biological macromolecules and membranes. By recording the time variation of the fluorescence frequency, thermal atomic fluctuations in the vicinity of the chromophore can be probed. From such fluorescence Stokes shift (FSS) experiments, it has been inferred that water motions in ...

1 CSIR-NAL, Bangalore, India 2 CSIR-NAL, Bangalore, India Abstract The exciting features of metamaterial in conjunction with transformation optics leads to various applications in the microwave regime with such examples as invisible cloak, frequency selective surfaces (FSS), radomes, etc. The concept of electromagnetic invisibility is very much important in aerospace platform. Hence to study th...

An efficient strategy for reducing the signature of an antenna is to substitute the conventional solid ground plane with a patterned ground plane thus letting the incoming energy to pass through the structure except over the operating band of the antenna. However, in a real environment, the energy flowing through the FSS (Frequency Selective Surface) can be intercepted by eventual scatterers lo...