Dispersion Characteristics of the Dipolar Modes in a Wave Guide Partially Filled with a Magnetoplasma Column

1975 ◽  
Vol 53 (12) ◽  
pp. 1163-1178 ◽  
Author(s):  
G. L. Yip ◽  
S. Le-Ngoc
Keyword(s):  
Plasma Wave ◽  
Electromagnetic Wave Propagation ◽  
Axial Magnetic Field ◽  
Propagation Constant ◽  
Wave Guide ◽  
Dispersion Characteristics ◽  
Resonant Frequencies ◽  
Special Cases ◽  
Close Study ◽  
Asymptotic Dispersion

The electromagnetic wave propagation in a partially filled plasma wave guide is studied by using both the quasistatic and the exact analyses. The cutoff and resonant frequencies are examined analytically to predict all possible modes, and numerical methods are then used to study the complete dispersion characteristics. Because of the geometrical generality of the problem, the fully filled plasma wave guide and the plasma column in free space can be considered as special cases. The classifications of the modes existing in various regions are clarified. The effect of the ratio of the plasma and wave guide radii and the d.c. axial magnetic field on the modes is observed and discussed. With a close study of cutoffs, it is shown that the 'special unpaired mode,' named by Bevc, can now be paired with another mode in the gyroresonance region. For large values of the propagation constant, asymptotic dispersion equations can be derived and turn out to be the same in both analyses. Comparisons between the two sets of results are also made to examine the validity of the quasistatic analysis.

Electromagnetic wave propagation in a chiroplasma-filled waveguide

1999 ◽  
Vol 62 (1) ◽  
pp. 87-94 ◽  
Author(s):  
J. GONG
Keyword(s):  
Wave Propagation ◽  
Electromagnetic Wave ◽  
Cross Section ◽  
Electromagnetic Waves ◽  
Electromagnetic Wave Propagation ◽  
Propagation Constant ◽  
Circular Cross Section ◽  
Propagation Characteristics ◽  
Waveguide Modes ◽  
The Family

A dispersion equation is derived for a cylindrical waveguide of circular cross-section partially filled with chiroplasma. The propagation characteristics of electromagnetic waves in the family of waveguide modes are studied. The dispersion curves are given. It is found that the propagation constant changes almost linearly with the chirality admittance for the parameters that we choose, and increases with increasing filled area.

Study on the Dispersion Characteristics of Surface TM Modes in Hollow Slab Waveguide with a Left-Handed Material Cover

2013 ◽  
Vol 710 ◽  
pp. 178-181
Author(s):  
Su Ping Li ◽  
Yan Chen ◽  
Wei Wu
Keyword(s):  
Dispersion Relation ◽  
Propagation Constant ◽  
Existence Condition ◽  
Slab Waveguide ◽  
Dispersion Characteristics ◽  
Dielectric Slab ◽  
The Core ◽  
Left Handed ◽  
Normalized Parameters ◽  
Asymmetry Measure

The dispersion characteristics of surface TM modes in a hollow slab waveguide which consists of the core and substrate of right-handed material (RHM) and the cover of left-handed material (LHM) are investigated. Normalized frequency, normalized propagation constant and asymmetry measure are introduced to the left-handed material hollow slab waveguide. The dispersion relation is derived by using these normalized parameters, and universal dispersion curves are obtained by solving transcendental dispersion equations analytically. Existence condition and other dispersion characteristics of guided surface TM modes have been discussed in detail for different permittivity of three layers for this left-handed material hollow dielectric slab waveguide.

scholarly journals An Insight into Creeping Electromagnetic Waves around the Human Body

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Branimir Ivsic ◽  
Davor Bonefacic ◽  
Zvonimir Sipus ◽  
Juraj Bartolic
Keyword(s):  
Wave Propagation ◽  
Human Body ◽  
Electromagnetic Waves ◽  
Electromagnetic Wave Propagation ◽  
Axial Magnetic Field ◽  
Magnetic Dipoles ◽  
Wearable Antennas ◽  
Field Decay ◽  
Theoretical Considerations ◽  
Insight Into

The electromagnetic wave propagation around human body torso is modelled by considering elementary electric and magnetic dipoles over an infinite muscle-equivalent cylinder. The poles in the spectral domain Green’s function with smallest imaginary part are found to correspond to creeping wave propagation coefficients which predict the general trend in propagation around human body. In addition, it was found that axial magnetic field component is crucial for communication via creeping waves since it generates modes with smaller field decay compared to axial electric field. The developed model may thus serve as a practical guideline in design of on-body wearable antennas. The theoretical considerations are verified with simulations and measurements on the prototype of PIFA antenna placed on the human body.

Theory of high-frequency waves in a coaxial plasma wave guide

1999 ◽  
Vol 6 (10) ◽  
pp. 3778-3787 ◽  
Author(s):  
B. Maraghechi ◽  
B. Farrokhi ◽  
J. E. Willett
Keyword(s):  
Plasma Wave ◽  
High Frequency ◽  
Wave Guide ◽  
High Frequency Waves

scholarly journals Modeling and Simulation of stochastically deformed Waveguides using Schelkunoff's Method

2018 ◽  
Vol 16 ◽  
pp. 35-41
Author(s):  
Hoang Duc Pham ◽  
Soeren Ploennigs ◽  
Wolfgang Mathis
Keyword(s):  
Cross Sections ◽  
Electromagnetic Waves ◽  
Analytic Solution ◽  
Propagation Constant ◽  
Circular Waveguide ◽  
Transverse Field ◽  
Field Pattern ◽  
Coupled Mode ◽  
Special Cases ◽  
Cylindrical Waveguides

Abstract. This paper deals with the propagation of electromagnetic waves in cylindrical waveguides with irregularly deformed cross-sections. The general theory of electromagnetic waves is of high interest because of its practical use as a transmission medium. But only in a few special cases, an analytic solution of Maxwell's equations and the appropriate boundary conditions can be found (Spencer, 1951). The coupled-mode theory, also known as Schelkunoff's method, is a semi-numerical method for computing electromagnetic waves in hollow and cylindrical waveguides bounded by perfect electric walls (Saad, 1985). It allows to calculate the transverse field pattern and the propagation constant. The aim of this paper is to derive the so-called generalized telegraphist's equations for irregular deformed waveguides. Subsequently, the method's application will be used on a circular waveguide as an illustrating example.

DISPERSION CHARACTERISTICS OF PLASMA WAVE-PACKETS

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-559-C7-560
Author(s):  
R. J. Vidmar ◽  
F. W. Crawford
Keyword(s):  
Plasma Wave ◽  
Wave Packets ◽  
Dispersion Characteristics

scholarly journals Dynamics of building-soil interaction

1973 ◽  
Vol 63 (1) ◽  
pp. 9-48 ◽  
Author(s):  
Paul C. Jennings ◽  
Jacobo Bielak
Keyword(s):  
Damping Ratio ◽  
Normal Modes ◽  
Elastic Half Space ◽  
Earthquake Response ◽  
Resonant Frequencies ◽  
Linear Elastic ◽  
State Response ◽  
Special Cases ◽  
Fixed Base ◽  
Base Structure

abstract In this study of the dynamics of building-soil interaction, the soil is modeled by a linear elastic half-space, and the building structure by an n-degree-of-freedom oscillator. Both earthquake response and steady-state response to sinusoidal excitation are examined. By assuming that the interaction system possesses n+2 significant resonant frequencies, the response of the system is reduced to the superposition of the responses of damped linear oscillators subjected to modified excitations. The results are valid even though the interaction systems do not possess classical normal modes. For the special cases of single-story systems and the first modes of n-story systems, simplified approximate formulas are developed for the modified natural frequency and damping ratio and for the modified excitation. Example calculations are carried out by the approximate and more exact analysis for one-story, two-story and ten-story interaction systems. The results show that interaction tends to decrease all resonant frequencies, but that the effects are often significant only for the fundamental mode for many n-story structures and are more pronounced for rocking than for translation. If the fixed-base structure has damping, the effects of interaction on the earthquake responses are not always conservative, and an increase or decrease in the response can occur, depending on the parameters of the system.

Electromagnetic Wave Propagation

2020 ◽  
pp. 78-88
Author(s):  
Magdalene Wan Ching Goh
Keyword(s):  
Wave Propagation ◽  
Electromagnetic Wave ◽  
Electromagnetic Radiation ◽  
Electromagnetic Wave Propagation ◽  
Propagation Constant ◽  
Characteristic Impedance ◽  
Helmholtz Equations ◽  
Basic Principles ◽  
Atmospheric Windows

Electromagnetic wave propagation is an invisible phenomenon that cannot be detected by the human senses. To understand wave propagation, one must first learn what wave propagation is and the basic principles that affect wave propagation. This chapter introduces the atmospheric windows which allow electromagnetic radiation from bands to penetrate Earth. Helmholtz equations, i.e. the equations which govern wave propagation, and the properties of waves (such as propagation constant and characteristic impedance) are then briefly explained. When waves encounter different media during its propagation, they may be reflected, refracted, or diffracted. These phenomena are also covered. The last part of this chapter concisely explains the terminologies commonly used to describe electromagnetic radiation.

Rapid calculation method for wave-guide-immersed dielectric resonant frequencies

2006 ◽  
Vol 84 (4) ◽  
pp. 289-297 ◽  
Author(s):  
Rudolf Nistor ◽  
Emil Petrescu
Keyword(s):  
Experimental Data ◽  
Calculation Method ◽  
Analysis Procedure ◽  
Wave Guide ◽  
Resonant Frequencies ◽  
Dielectric Sample ◽  
Margin Of Error ◽  
Rapid Calculation ◽  
Electrical Permittivity ◽  
Good Agreement

A rapid calculation is used to obtain the resonant frequencies of a dielectric sample excited in a semi-infinite wave guide. An analysis procedure for a sample excited in a semi-infinite wave guide is carried out to show the effect of the sample's dimensions and electrical permittivity. The theoretical resonant frequencies of the resonators are predicted and compared with those measured. The theoretical values of the resonant frequencies are in good agreement with experimental data within a margin of error less than 8%. PACS Nos.: 32.30.Bv, 41.20.Jb

Sign in / Sign up

Export Citation Format

Share Document