FDTD Method Simulation with Perfect Matching Layer at GSM Frequency

The finite-difference time-domain (FDTD) method is one of the most widely used computational methods in electromagnetic. This paper study the simulation of wave propagation using one and two Finite Difference Time Domain method has been studied. It being used to study the time evolution behavior of electromagnetic field by solving the Maxwell's equation in time domain using perfect matching layer boundary condition. The basic idea is this that the amount of reflected waves is dictated by the intrinsic impedance of the two medium. The software is developed using Matlab programming language. Numerical examples validate the software. is more general since it includes both the propagating mode regime and the evanescent mode regime. Robert et al studied an adaptive finite element method for the wave scattering with transparent boundary [10]. Also viewpoint allows PMLs to be derived for inhomogeneous media such as waveguides, as well as for other coordinate systems and wave equations [11]. In this work we studied the simulation of global system mobile wave propagation using one and two Finite Difference Time Domain method. It being used to study the time evolution behavior of electromagnetic field by solving the Maxwell's equation in time domain using perfect matching layer boundary condition

Computational Modeling of SAR and Heat Distribution in Lossy Medium at GSM Frequencies

In recent years, institution has increased imposition of electromagnetic radiation in many applications. This radiation react with the human tissue and may lead to harmful and injurious effects on human health. However a finite difference thermal model of lossy medium as (spinal cord of human body) has been developed to calculate temperature rises generated in the spinal cord by radiation from cellular telephones with different frequencies. The natural metabolic heat production and the power density absorbed from the electromagnetic field have been evaluated. The specific absorption rate (SAR) was derived from a finite difference time domain model (FDTD) of the spinal cord. This is a numerical analysis is technique used for modeling computational electrodynamics. Aside from the specific absorption rate, through the exposure of radiation is an extremely important parameter while assessing the effects on spinal cord tissue. The heat distribution was calculated using the bioheat equation coupled with Maxwell's equation. A one dimensional finite difference time domain method has been used, some simulations for electromagnetic wave through the spinal cord tissue is made using software program. Also for the simulation, the dielectric properties supposed medium are directly taken by numerical program. Results show that electromagnetic fields penetrate the life tissues and attenuate fast to reach zero at large time steps. Specific absorption rate show maximum at the first boundary of tissue and becomes less value by using high frequency. The absorbent power and specific absorption rate show maximum at the interface of tissue, and the technique developed may be used to estimate temperature rises associated with specific absorption rate (SARs) for different types of radiation. Also, the results note that low-frequency waves have significantly affected the biological tissue

Z Transform and FDTD Method in Unmagnetized Plasma

The Z transform is typically used in digital filtering and signal processing problems. The paper illustrates the use of the Z transform in implementing the FDTD method where it is useful to avoid dealing with convolution integral in the time domain by going immediately to Z domain. This work study the pulse propagation in free space that comes upon a plasma. Plasma is very interesting medium and the results illustrated that at low frequencies, it looks like a metal, and higher frequency, it become transparent just like a dielectric medium

Numerical Study The Dielectric Properties And Specific Absorption Rate Of Nerve Human Tissue At Different Frequencies

The study of electromagnetic radiation effects on human body is a very important subject, due to the possible health effects, these electromagnetic waves can cause in life tissue. In this paper, the dielectric properties and specific absorption rat (SAR) distribution in nerve human tissues exposed to electromagnetic radiation with different frequencies is studied. We modeled nerve tissue by layered system. Finite difference time domain (FDTD) computations were used to evaluator the electric, magnetic field, and specific absorption rate. Results show the dielectric properties as conductivity, relative permittivity and penetration depth of nerve tissue plotted with different frequencies. A one dimensional FDTD algorithm has been built, some simulations for electromagnetic wave through the nerve tissue is made. Results show that electromagnetic fields penetrate the life tissues and attenuate fast to reach zero at large time steps. SAR show maximum at the first boundary of tissue and becomes less value by using high frequency. Also, the result appear that penetration depth and relative permittivity decreased by increasing frequency

Numerical Study The Dielectric Properties And Specific Absorption Rate Of Nerve Human Tissue At Different Frequencies

The study of electromagnetic radiation  effects on human body is a very important subject, due to the possible health effects, these electromagnetic waves  can cause in life tissue. In this paper, the  dielectric properties  and specific absorption rat (SAR) distribution in  nerve  human tissues exposed to electromagnetic radiation with different frequencies is studied . We modeled  nerve  tissue by layered system. Finite difference time domain (FDTD) computations were used to evaluator the electric, magnetic field, and specific absorption rate. Results show the dielectric properties as  conductivity, relative permittivity and penetration depth  of  nerve tissue plotted with different frequencies. A one dimensional FDTD algorithm has been built, some simulations for electromagnetic wave through the nerve  tissue is made. Results show that electromagnetic  fields penetrate the life tissues and attenuate fast to reach zero at large time steps. SAR show maximum at the first boundary of tissue  and becomes less value by using high frequency. Also, the result appear that penetration depth and relative permittivity decreased by increasing frequency

Scaling 5ules for a 6lab: aveguide 6tructure &omprising 1onlinear and 1egative, ndex 0aterials

We consider a Kerr-type nonlinear guiding layer surrounded by at least one medium made of a negative index material (NIM). Three different structures are investigated in this work. The first structure has a NIM cladding, the second has a NIM substrate, and the third has a NIM substrate and cladding. Three normalized parameters are used to study the dispersion characteristics of these waveguide structures. The dispersion curves are obtained and the effect of the NIM parameters on the guidance properties is presented. It is found that the dispersion characteristic of nonlinear waveguide structure with NIM cladding and dielectric substrate are similar to those for the same structure with NIM substrate and dielectric cladding. However, when both of them are NIMs new properties can be seen

Nonlinear TE Electromagnetic Surface Waves in a Ferrite Layered Structure

Characteristics of TE electromagnetic surface waves propagating in a nonlinear dielectric film bounded by a ferrite cover are examined theoretically. A dispersion relation based on Jacobian Elliptic Functions is derived, which describes the behaviour of the nonreciprocal nonlinear waves. ) TE ( . ) Jacobian Function (

Characteristics of electromagnetic waves in slab waveguide structures comprising chiral nihility film and left-handed material claddings

We analytically present the dispersion equation of an asymmetric three-layered chirowaveguides, in which the core and the claddings are different chiral materials. Then, we produce the dispersion equation for a symmetric three-layered chirowaveguides, in which the claddings chiral materials are the same, but different from the one in the core. After that, two modes of propagation through a chiral nihility core and left handed material (LHM) claddings waveguide are treated in details. The characteristic equations and the cut-off frequencies for both even and odd modes are derived. The electric field profiles are plotted and discussed. We show that each mode (odd and even) can be separated into right-handed and left-handed circularly polarized (RCP and LCP) modes. The results reveal that novel properties such as peculiar dispersion curves

Frequency Dependent FDTD Formulation for Debye Medium

According to the rapidly growing use of finite difference time domain method (FDTD) in numerical electromagnetic, this technique can be used to solve problems involving complex permittivity such as a dispersive materials. Since the dielectric constant for such media vary with frequency. In this paper we simulate and study the electromagnetic waves with different frequencies through Debye medium using (FDTD) method, Debye model describes a single pole frequency dependence. The results shows a simulation of a pulse going into frequency dependent dielectric material. Also we evaluate electric field,magnetic field and power density in dispersive medium with different frequencies. Noticed that at higher relative dielectric constant with lower frequency produced smaller amplitude, and the amplitude attenuated rapidly at high frequency. It is the most widely used time domain numerical method largely due to the simplicity of the solution algorithm

RESPONSE OF CORN (ZEA MAYS), BASIL (OCIMUM BASILICUM) AND EGGPLANT (SOLANUM MELONGENA) SEEDLINGS TO WI-FI RADIATION.

The objective of the present study was to investigate the changes of growth related aspects of seedlings after being exposed to Wi-Fi radiation. Experiment was carried out by exposing seedlings to radiation from a Wi-Fi router. The test seedlings and the control were subjected to the same environment during four weeks. The results showed that corn seedlings when exposed to Wi-Fi radiation grew faster and have shoot length and stem thickness significantly larger than the other control. On the other hand basils and eggplants, both exposed and not exposed to Wi-Fi radiation, were found with no significant effects on the shoot length and stem thickness. Moreover Wi-Fi radiation significantly reduced the fresh weight of corns and basils, whereas eggplants were not affected. Furthermore Wi-Fi radiation significantly increased the dry weight of eggplants, whereas corns and basils were not affected. Finally, the results showed that Wi-Fi radiation significantly decreased the water content of three tested seedlings. The study concluded that the Wi-Fi radiation may alter growth related characters of seedlings