This paper presents an extension to the rectangular dielectric waveguide technique to obtain the permittivity of samples iteratively from the effective refractive index measurements by using the solution of the wave equation. The effective refractive index is presented for several samples in the 33 GHz to 50 GHz frequency range. The method is very fast and simple and provides an accuracy of bet...

Multilayer antennas—for example, stacked patches—often employ low permittivity substrates, such as foams. These foams, however, tend to be fragile, difficult to glue, and difficult to bend. In a previous contribution, the authors described how a Duroid substrate may be drilled in order to obtain a low permittivity synthetic dielectric. This paper shows, by means of both practical and numerical ...

Recently, there has been significant interest toward the development of tunable dielectric materials for voltage-controlled, frequency-agile phase shifters and filters operating in the microwave regime. The fundamental challenge in designing materials systems for such tunable devices is the simultaneous requirement of high dielectric tunability ([40%) over a large temperature interval (-10 C to...

In recent years, the study of newer types of dielectric materials and compositions has been of great interest. The quest for new, innovative and easily obtainable dielectric materials that yield predictable and controllable permittivity and permeability values with very low dielectric loss has always been fruitful. New ideas and designs to implement these materials in microwave devices and stru...

In this paper, we have simulated a single-pin-shorted microstrip line fed three-dielectric-layer (with different permittivity and thickness) rectangular patch microstrip antenna for all those communication systems whose limited antenna size is premium. Low permittivity hard foam has been used as one substrate to achieve wide bandwidth. The simulation of this proposed antenna has been performed ...

Proton accelerator structures for medical applications using Dielectric Wall Accelerator (DWA) technology allow for the utilization of high electric field gradients on the order of 100 MV/m to accelerate the proton bunch. Medical applications involving cancer therapy treatment usually desire short bunch lengths on the order of hundreds of picoseconds in order to limit the extent of the energy d...

A dielectric mixing model has been developed to calculate the complex permittivity of wet soils at 5.65 GHz (C-band) and 9.5 GHz (X-band) microwave frequencies. The model considers the complex permittivity of dry soil as initial parameter. The complex permittivity of wet soil has been estimated in terms of the complex permittivity of dry soil, the complex permittivity of water at a given microw...

This paper describes the design and mode structure of resonators using Bragg confined modes. We investigate a range of low-loss dielectric materials with aim to maximize the Q-factor. The structure is composed of a hollow dielectric cylinder with the mode confined in the central low-loss region. We illustrate the importance of material permittivity and show it is possible to obtain a better Q-f...

– A statistical mechanics expression is derived for the space-dependent dielectric permittivity of a polar solvent near an interface. The asymptotic behaviour of this local per-mittivity is calculated in the low density limit, near a planar interface. The potential of mean force between two ions is shown to agree with the prediction of macroscopic electrostatics for large separations parallel t...