Using a local plane wave assumption, one can determine the normal incidence sound absorption coefficient of a surface by measuring the acoustic pressure and the particle velocity normal to that surface. As the measurement surface lies in front of the material surface, the measured active and incident acoustic power will generally deviate from those at the material surface, leading to a possibly...

Two absorbing boundary conditions (ABC’s) are derived for the cylindrical MRTD grids. The first one is the convolutional perfectly matched layer (CPML) based on stretched coordinates with complex frequency shifted constitutive parameters, and the other is the straightforward extension of CPML named quasi-CPML (QCPML) as it is no longer perfectly matched for cylindrical interfaces. Unlike the Be...

Rapid advancements and wide spread of microwave- RF-communication systems over the years have led to an abundant increase in electromagnetic energy radiation our living environment. Such microwave sources is due development advancement communication techniques (mobile phones, laptops, antennas for aeronautics or automobile) electronic warfare military field (radar satellite). Recently research ...

We report herein the synthesis of a novel nest structured electromagnetic composite through in-situ chemical polymerization of 3-methyl thiophene (3MT) in the presence of the BaFe11.92(LaNd)0.04O19-TiO2 (BFTO) nanoparticles and MCNTs. As an absorbing material, the BFTO/MCNTs/P3MT/wax composites were prepared at various loadings of BFTO/MCNTs/P3MT (0.2:0.10:1.0 ~ 0.2:0.30:1.0), and they exhibite...

<span>For materials characterization, several methods have been developed. Most of them need a sample to be machined prior testing process. Hence, they are destructive and cannot used for in-situ radar absorbing coatings testing. This requires employing suitable measurement technique extract their electromagnetic properties quickly accurately. In this paper, the swept frequency probe refl...

The thesis addresses time-domain inverse electromagnetic scattering for determining unknown characteristics of an object from observations of the scattered field. Applications include non-destructive characterization of media and optimization of material properties, for example the design of radar absorbing materials. Another interesting application is the parameter optimization of subcell mode...