7 research outputs found
Electromagnetic Field Interaction with Metamaterials
It is well known that constitutive parameters, namely, the electrical permittivity, ε, and the magnetic permeability, μ, in a medium determine the response and reaction of such medium or material when exposed to external time-varying electromagnetic fields. Furthermore, most materials are lossy and dispersive, that is, both permittivity and permeability are complex and frequency-dependent. Interestingly, by controlling the sign of real parts of ε and μ in a medium, unique electromagnetic properties can be achieved that are not readily available in nature. Recently, subwavelength composite engineered structures, also known as metamaterials, have evolved in many engineering and optical applications, due to their unique electromagnetic properties that are not found in nature, including but not limited to negative refractive index, backward wave propagation, subwavelength focusing and super lenses, and invisibility cloaking. The main aims of this chapter are to provide an overview of electromagnetic field behavior and interaction with metamaterials and to explore such behavior in various metamaterials both analytically and numerically
Magnetostatic waves in metallic rectangular waveguides filled with uniaxial negative permeability media
The propagation characteristics of magneto-quasistatic waves, more commonly,
known as magnetostatic waves in a long, metallic rectangular waveguide filled
with a metamaterial slab are comprehensively investigated. The metamaterial
slab consists of split-ring resonators as an anisotropic uniaxial medium with
transversal negative effective permeability. Some analytical relations and
numerical validations on the characteristics of these waves are presented. The
results include the dispersion relations, mode patterns (field distributions)
that can be supported by such media and their corresponding cutoff frequencies,
group velocities, power flows, and storage energies of magnetostatic waves. The
findings from the present research study can be advantageous to advance the
synthesis and development of negative permeability materials with peculiar
features in guiding structures.Comment: 9 pages, 6 figure
Microwave Sensors for Soil Moisture Detection: An Application toward Healthy Date Palm
Soil moisture is an important key parameter in the earth ecosystem that has an impact on both landscape and atmospheric conditions. Moreover, sudden changes to soil moisture due to environmental conditions result in degradation to food plants and, thus, may consequently affect food yields. This chapter aims to investigate numerically an application for crops health through soil moisture detection using microwave-based sensors. The numerical studies are carried out using full-wave electromagnetic simulations. More emphasis on the numerical setup of microwave antennas with customized modeled soil layer is presented
A Less Complex Algorithmic Procedure for Computing Gray Codes
The purpose of this paper is to present a new and faster algorithmic procedure for generating the n bi Gray codes. Thereby, through this paper we have presented the derivation, design and implementation of a newly developed algorithm for the generation of an n-bit binary reflected Gray code sequences. The developed algorithm is stemmed from the fact of generating and properly placing the min-terms from the universal set of all the possible min-terms [m0 m1 m2 …. mN] of Boolean function of n variables, where, 0 < N < 2n-1. The resulting algorithm is in concise form and trivial to implement. Furthermore, the developed algorithm is equipped with added attributes of optimizing of time and space while executed
A Less Complex Algorithmic Procedure for Computing Gray Codes
The purpose of this paper is to present a new and faster algorithmic procedure for generating the n bi Gray codes. Thereby, through this paper we have presented the derivation, design and implementation of a newly developed algorithm for the generation of an n-bit binary reflected Gray code sequences. The developed algorithm is stemmed from the fact of generating and properly placing the min-terms from the universal set of all the possible min-terms [m0 m1 m2 …. mN] of Boolean function of n variables, where, 0 < N < 2n-1. The resulting algorithm is in concise form and trivial to implement. Furthermore, the developed algorithm is equipped with added attributes of optimizing of time and space while executed