Frequency scanning Fabry–Pérot cavity antenna with single 2D‐varying partial reflecting surface

Parametric analysis of a broadband Archimedean spiral antenna with cavity

In this article an Archimedean spiral antenna is designed and analyzed that has good operation in broadband application. By analyzing this design, the effects that different parameters have on antenna operation will be studied and ways of optimization will be found.  Influences of cavity height and number of turns to obtain good matching and gain in a frequency interval of 4 to 18 GHz will be d...

Reflecting Cavity Blackbodies for Radiometry

Nearly 20 years ago Quinn and Martin presented a novel blackbody design with an absorbing end face and highly reflecting side walls. This blackbody had the considerable advantage of being less sensitive to temperature gradients along the side walls (potentially of several degrees Celsius) compared to an all-black cavity. Recent work at NPL has developed this concept further, laying out the conc...

A scanning cavity microscope

Imaging the optical properties of individual nanosystems beyond fluorescence can provide a wealth of information. However, the minute signals for absorption and dispersion are challenging to observe, and only specialized techniques requiring sophisticated noise rejection are available. Here we use signal enhancement in a high-finesse scanning optical microcavity to demonstrate ultra-sensitive i...

Miniature Antenna with Frequency Agility

Gain Improvement of Microstrip Patch Antenna Using Negative Permeability Metamaterial Reflecting Surface

Abstract:This methodology involves complementary square split ring resonators and a microstrip patch antenna both designed to resonate at same frquency.The proposed antenna is made by using metamaterial reflecting surface to obtain the maximum gain hight of reflecting surface is adjusted.we uses an array of squared split ring resonator (SRR) printed on a low dielectric constant material as the ...