Abstract Distributed Bragg reflectors (DBRs), comprised of periodic refractive index changes, are widely used in optoelectronic devices as resonators, filters and sensors. The heterostructures required for DBRs can be difficult to implement nanostructures due poor compositional control on the nanoscale. In present paper, simulation results presented reflectance spectra from DBR structures that ...

This paper begins with a quick survey of potential space applications and brief review previous experiments on the shape control spherical shell reflector thin film PVDF-TrFE. Next, problem thermal sensitivity is addressed numerically; it found that, because large expansion active material, surface figure error generated by linear gradient unimorph considerable its correction requires voltages....

A synthetic aperture radar (SAR) system requires external absolute calibration so that radiometric measurements can be exploited in numerous scientific and commercial applications. Besides estimating a calibration factor, metrological standards also demand the derivation of a respective calibration uncertainty. This uncertainty is currently not systematically determined. Here for the first time...

Ground penetrating radar (GPR) systems are equipment able to acquire underground images scanning the surface of soil/pavement under investigation. Usually GPR records its own position along scan line using a mechanical odometer, i.e., rolling wheel in contact with ground. Unfortunately, this simple and cheap solution can be not effective on uneven terrains. In article, completely different is p...

Organic wavelength-selective mirrors are used to reduce the loss of emitted photons through the surface of a luminescent solar concentrator (LSC). A theoretical calculation suggests that application of a 400 nm broad reflector on top of an LSC containing BASF Lumogen Red 305 as a luminophore can reflect 91% of all surface emitted photons back into the device. Used in this way, such broad reflec...

A reflector antenna utilizing three planar reflectors and a 3/4 X-unipole radiator is proposed. Calculations based on image and EMF-methods predict that the gain is about 5 dB greater than that of the two-dimensional comer reflector antenna, and that the input impedance is roughly between 50 and 75 9. Experiments conducted on the three-dimensional corner reflector antenna with rectangular comer...