The analysis of resonant frequency for anisotropic artificial circular dielectric resonator (CDR) encapsulated in waveguide is investigated theoretically. The anisotropic permittivity of CDR is established by taking a relative permittivity value in one direction higher than the values of other directions in cylindrical coordinate system. By deriving Maxwell time-dependent curl equations for the...

Electrically small oblate spheroidal and spherical antennas in confocal shells with negative permittivity represent perspective antenna design to combine moderately small size, wide bandwidth, high efficiency and power of radiation. However, optimization of the antennas performance parameters imposes contradictory restrictions on permittivity of the shells, electrical size of the antennas, shap...

-The crystalline and osmotic swelling of N~, Cs-, Mgand Ca-montmorillonite has been measured in dimethyl sulphoxide and in formamide, N-methyl formamide, dimethyl formamide, N-methyl acetamide and dimethyl acetamide. These liquids have similar dipole moments but their relative permittivities vary appreciably from values less than water to values greater than water. Na montmorillonite exhibits o...

In this paper, an ideal cylindrical metamaterial invisibility cloak with infinite-length which its electric permittivity and magnetic permeability mapped to the Drude dispersion model is simulated. The sinusoidal plane waves with microwave frequencies used as sources. To this end, the dispersive finite-difference time-domain method (FDTD) used with Convolutional Perfectly Matched Layered (CPML)...

The accurate characterization of the temperature-dependent permittivity of aluminum nitride (AlN) ceramic is quite critical to the application of wireless passive sensors for harsh environments. Since the change of the temperature-dependent permittivity will vary the ceramic-based capacitance, which can be converted into the change of the resonant frequency, an LC resonator, based on AlN cerami...

Different perturbation theories for the relative permittivity of dipolar model fluids are assessed by comparison to a comprehensive set molecular dynamics (MD) simulation data Stockmayer fluids. With exception dense liquids, all MD univariate function so-called dipole strength y. Overall, good agreement is found between some and data.

We present preliminary results from a method for estimating the optimal effective permittivity for reconstructing microwave-radar images. Using knowledge of how microwave-radar images are formed, we identify characteristics that are typical of good images, and define a fitness function to measure the relative image quality. We build a polynomial interpolant of the fitness function in order to i...

A change in the relative proportions of a mixture of rubber tire dust and rice husks will cause a change in the mixture’s electrical permittivity and its ability to absorb electromagnetic energy. An openended coaxial probe was used in conjunction with three dielectric mixture equations (the Kraszewski equation, the Landau equation and the Lichtenecker equation) to obtain the dielectric properti...

Ultra-wideband pulse radar exhibits high range resolution, and excellent capability in penetrating dielectric media. With that, it has great potential as an innovative non-destructive inspection technique for objects such as human body or concrete walls. For suitability in such applications, we have already proposed an accurate permittivity estimation method for a 2-dimensional dielectric objec...