Henning F. Harmuth’s research while affiliated with Catholic University of America and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (89)


Electric Field Strength Due to Electric Excitation
  • Chapter

January 2000

·

6 Reads

Henning F. Harmuth

·

We start with the modified Maxwell equations without electric and magnetic charges, having constant scalars for the permeability µ and the permittivity ϵ. The following equations apply to a medium at rest: curlH=Et+gecurlH = \in \frac{{\partial E}}{{\partial t}} + {{g}_{e}} (1)curlE=μHt+gm- curlE = \mu \frac{{\partial H}}{{\partial t}} + {{g}_{m}} (2)epsilondivE=μdivH=0epsilon divE = \mu divH = 0 (3)ϵE=D,μH=B\epsilon E = D,\mu H = B (4) We restrict the investigation to currents that are carried either by electric or magnetic dipoles and avoid any monopole currents. This assumption will be ideally satisfied in a medium with atomic hydrogen, if any ionization can be neglected. For the electric dipole current density we use Eq.(1.2-11), writing the partial derivative ∂ge /∂t since the current density may now be a function of location as well as of time, \begin{array}{*{20}{c}} {{{g}_{e}} + {{\mathcal{T}}_{{mp}}}\frac{{\partial {{g}_{e}}}}{{\partial t}} + \frac{{{{\mathcal{T}}_{{mp}}}}}{{\mathcal{T}_{p}^{2}}}\int {{{g}_{e}}dt = {{\sigma }_{p}}E} } \\ {{{\sigma }_{p}} = \frac{{{{N}_{0}}{{e}^{2}}{{\mathcal{T}}_{{mp}}}}}{m}} \\ \end{array} (5) but the use of Eqs.(1.3-26), (1.3-29), (1.3-31), and (1.3-32) for the magnetic dipole current density gm(t) runs into the difficulty of containing the function sin ϑ. There is little hope of finding an analytical solution of Maxwell’s modified equations (1)–(4) if the magnetic dipole current density gm is defined by a transcendental differential equation. We get around this difficulty by observing that the plots of Figs.1.3-3 and 1.3-5 for a hypothetical magnetic charge dipole are similar to the plots of Figs.1.3-11 and 1.3-10 for a bar magnet dipole.


Appendix

January 2000

·

5 Reads

Advances in Imaging and Electron Physics

The direct numerical evaluation of Eq.(2.4-45) by computer runs into difficulties. To recognize the reason we list in Tables 6.1-1 typical values of λ1, λ2, λp1, and λp2. The magnitude of λl and λ2 lies between 1 and 2.51 x 10-3 for p ≥ 0.05 but the magnitude of c pλp1 for ŋ in the range from 1 to 100 and c p = 1.98 x 10-12 is in the order of 10-14 to 10-19 and c pλp2 is even smaller except when p is very close to 0.5. The computer must produce small differences of numbers of the order of 1020, which requires too much precision. Our way around this difficulty uses a series expansion in powers of c p.


Electromagnetic Signals in Astronomy

January 2000

·

15 Reads

Most of the information we have obtained about the universe beyond the planet Earth came from electromagnetic waves, and most of the information obtained from electromagnetic waves came from steady state waves. Whenever received electromagnetic waves are decomposed into sinusoidal waves with various frequencies one thinks and acts in terms of steady state wave theory. The Doppler shift of a frequency—implied every time the term red-shift is used—is a steady state concept even though the Doppler effect is not. A frequency spectrum of received waves is a steady state concept.


Associated Field Strengths

January 2000

·

3 Reads

We rewrite Eqs.(2.1-45) and (2.1-60) in normalized form for the derivation of the associated magnetic field strength. First we get with the help of Eqs.(2.1-32) and (2.1-48): \begin{array}{*{20}{c}} {\frac{{{{\tau }_{{1m}}}{{\tau }_{{2m}}}}}{{{{\tau }_{{2m}}} - {{\tau }_{{1m}}}}} = - \frac{{{{\tau }_{{mp}}}}}{{{{{\left( {1 - 8\alpha '{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}} \\ {{{\tau }_{{1m}}} = {{\tau }_{{mp}}}\frac{{1 + {{{\left( {1 - 8{{{\alpha '}}_{1}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}{{4{{{\alpha '}}_{1}}{{\tau }_{{mp}}}}},{{\tau }_{{2m}}} = {{\tau }_{{mp}}}\frac{{1 + {{{\left( {1 - 8{{{\alpha '}}_{1}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}{{4{{{\alpha '}}_{1}}{{\tau }_{{mp}}}}}} \\ {t/{{\tau }_{{1m}}} = {{{v'}}_{1}}\theta /pq,t/{{\tau }_{{2m}}} = {{{v'}}_{2}}\theta /pq,\theta = t/\tau ,p = {{\tau }_{{mp}}}/{{\tau }_{p}},q = {{\tau }_{p}}/\tau } \\ {{{{v'}}_{1}} = \frac{{4{{{\alpha '}}_{1}}{{\tau }_{{mp}}}}}{{1 + {{{\left( {1 - 8{{{\alpha '}}_{1}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}},{{{v'}}_{2}} = \frac{{4{{{\alpha '}}_{1}}{{\tau }_{{mp}}}}}{{1 - {{{\left( {1 - 8{{{\alpha '}}_{1}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}} \\ {\frac{{{{\tau }_{{3m}}}{{\tau }_{{4m}}}}}{{{{\tau }_{{3m}}} - {{\tau }_{{4m}}}}} = - \frac{{{{\tau }_{{mp}}}}}{{{{{\left( {1 - 8{{{\alpha '}}_{2}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}} \\ {{{\tau }_{{3m}}} = {{\tau }_{{mp}}}\frac{{1 + {{{\left( {1 - 8{{{\alpha '}}_{2}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}{{4{{{\alpha '}}_{2}}{{\tau }_{{mp}}}}},{{\tau }_{{4m}}} = {{\tau }_{{mp}}}\frac{{1 + {{{\left( {1 - 8{{\alpha }_{2}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}{{4{{\alpha }_{2}}{{\tau }_{{mp}}}}}} \\ {t/{{\tau }_{{3m}}} = {{v}_{3}}\theta /pq,t/{{\tau }_{{4m}}} = {{v}_{4}}\theta /pq,\theta = t/\tau ,p = {{\tau }_{{mp}}}/{{\tau }_{p}},q = {{\tau }_{p}}/\tau } \\ {{{v}_{3}} = \frac{{4{{\alpha }_{2}}{{\tau }_{{mp}}}}}{{1 + {{{\left( {1 - 8{{\alpha }_{2}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}},{{{v'}}_{4}} = \frac{{4{{\alpha }_{2}}{{\tau }_{{mp}}}}}{{1 - {{{\left( {1 - 8{{\alpha }_{2}}{{\tau }_{{mp}}}} \right)}}^{{{{1} \left/ {2} \right.}}}}}}} \\ \end{array} ((1)) KeywordsField StrengthMagnetic Field StrengthElectric Field StrengthIntegration ConstantTime FunctionThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Introduction

January 2000

·

16 Reads

·

4 Citations

Consider Maxwell’s equations for a medium at rest with scalar constants for the permeability µ permittivity ϵ and conductivity σ. Furthermore, we have the electric and magnetic field strengths E and H, electric charge and current density ρ e and g e as well as electric and magnetic flux densities D and B. Using the International System of units we get:


Excitation Functions With Finite Rise Time

January 2000

·

10 Reads

In Section 2.5 we produced plots of the electric field strength for electric excitation functions with the time variations shown in Fig.2.5-1. The jump at θ = 0 makes these excitation functions less than desirable for physics. We had to use the functions according to Eq.(2.2-2) \begin{array}{*{20}{c}} {{{E}_{E}} = 0} & {for} & {\theta < 0} \\ { = {{E}_{{0e}}}^{{ - \theta r/pq}}} & {for} & {\theta 0} \\ \end{array} (1) for excitation since they are eigenfunctions of the differential equation Eq.(2.2-28). Two of the undesirable excitation functions according to Eq.(1) can be combined to a double exponential ramp function according to Fig.2.2-2 that avoids the jump at θ = 0: \begin{array}{*{20}{c}} {{{E}_{E}}\left( {0,\theta } \right) = 0} & {for} & {\theta < 0} \\ { = {{E}_{0}}\left( {{{e}^{{ - \theta r/pq}}} - {{e}^{{ - \theta s/pq}}}} \right)} & {for} & {\theta 0,s > r} \\ \end{array} (2)



Reflection and Transmission of Incident Signals

January 1999

·

7 Reads

Consider an electromagnetic wave excited in the plane of excitation in Fig2.1-1, beginning at the time t = t 0 The ‘beginning’ or front (plane) of the wave reaches the origin of a Cartesian coordinate system with the axes x, y, z at the time t = 0. The x-axis is assumed to be in the wave front and to stick out perpendicularly from the paper plane. The plane z = 0 is the boundary between two media characterized by the parameters εl, µl, σ1, s1 and ε2, µ2, σ2, s2. The angle of incidence between the boundary plane and the wave front is denoted υ2 in Fig2.1-1. All points y ≤ 0 of the boundary plane have been reached at a time t≤ 0 by the wave, while none of the points y > 0 have been reached yet at the time t = O. A reflected cylinder wave Cr is excited at the boundary plane z = 0 for any value y ≤ 0 in medium 1 and a transmitted cylinder wave Ct in medium 2. Fig2.1-1 is the basic illustration for the reflection and transmission of an incident planar wave. We will see in Section 2.2 that this illustration can be modified by the introduction of a signal boundary to produce a model that is better suited for waves that represent signals.


Signal Propagation and Detection in Lossy Media

January 1999

·

9 Reads

We start with the modified Maxwell equations of Section 1.1. They were written in Section 2.1 for Cartesian coordinates and planar TEM waves. The polarization was extracted by Eqs.(2.1–16), (2.1–17) and Eqs.(2.1–18), (2.1–19) were obtained. We can use these equations here but we leave out the indices i and 1 since we consider waves in one medium rather than at the boundary of two mediums:Ey+μHt+sH=0\frac{{\partial E}}{{\partial y}} + \mu \frac{{\partial H}}{{\partial t}} + sH = 0 \frac{{\partial E}}{{\partial y}} + \in \frac{{\partial E}}{{\partial t}} + \sigma H = 0



Citations (38)


... Fundamental criticism of the unquestioned use of Fourier transforms to infer conclusions in the time domain from the frequency domain is not new, but was delivered in a sustained and powerful form throughout the work of Harmuth, most notably [2], who wrote extensively on nonsinusoidal electromagnetic systems (waveguides, radars, sensors, antennas). For example, analytical formulas for nonsinusoidal travelling wave antennas were derived in [3]. ...

Reference:

Theory of Nonsinusoidal Small Antennas with Applications to Near-Field Communication System Analysis and Design
Propagation of Electromagnetic Signals
  • Citing Book
  • November 1994

... In the Soviet Union, in addition to mathematical research [84,85], another research direction in Walsh functions was focussed on their applications in system and logic design, which led to a series of papers followed by the first book on application of spectral techniques for the design of logic circuits [74]. The books by Harmuth [3,86], and Ahmed and Rao [87], which were translated with additional chapters on related research by Soviet researchers, certainly contributed to further research in this field, as did articles and books written by Soviet authors [88][89][90][91]. The book [92] was also very informative from the mathematical point of view, as it provided a global overview of the field, with an excellent selection of references, making it very influential in more recent earlier work, [16,26]. ...

Transmission of Information by Orthogonal Functions
  • Citing Article
  • January 1972

... It consists of Intergalactic plasma, Microwave background radiation, cosmic Far-Infrared background, Dark Matter particles including magnetic dipoles DIRACs and electric dipoles ELOPs. Cosmic Maxwell's equations should consider the macroscopically averaged electric dipole and magnetic dipole moment densities of the Medium in the presence of applied fields [28] as it has be done by H. Harmuth and K. Lukin [29] [30]. ...

Interstellar Propagation of Electromagnetic Signals
  • Citing Book
  • January 2000

... Among other examples of resistive/absorbing elements in antennas to improve pulse radiating efficiency the Large Current Radiator (LCR) by Harmuth should be mentioned [6][7][8]. In this radiator, it was proposed to shield and suppress with absorber the currents that produce unwanted radiation and thus achieve the short pulse dipole-like radiation. ...

Large-Current, Short-Length Radiator for Nonsinusoidal Waves
  • Citing Conference Paper
  • August 1983

... Such a belief has reasons when this problem is reducible to a slowly varying envelope approximation or any other asymptotic model. However, traditional MCA in combination with Fourier analysis faces major difficulties of both mathematical origin and physical nature when ultra-short signal handling problems arise [1,2]. Classical MCA fails completely as regards electromagnetic field evolving in nonlinear * E-mail: erden@ieee.org ...

ELECTROMAGNETIC TRANSIENTS NOT EXPLAINED BY MAXWELL'S EQUATIONS
  • Citing Chapter
  • June 1993

... The four, are relation between electric field E with conductive current J and electric displacement D. And the relation between magnetic field H with magnetic induction B and magnetic polarization M. In this section we apply the theorems and properties of preceding section to solve Maxwell's equations describing planar transverse electromagnetic wave (TEMP) propagating in lossy medium. The Laplace transform method and mathematical models were used to solve Maxwell's partial differential equations in [12, 13, 14, 17, 18, 20, 25]. Other than Laplace transform, F. B. M. Belgacem applied the new Sumudu transform [21, 22] to the Maxwell's equation in [8]. ...

Introduction
  • Citing Chapter
  • January 2000

... Such criticism of the unrestricted deployment of Fourier transform methods for solving electromagnetic wave propagation problems has lead to the revival of the controversy about how best to define signal propagation speed (inadequacy of the group velocity concept [14]). The climax, however, was the proposed correction of Maxwell's equations given in [11], [12] and further elaborated in [15]. † Other writers have also voiced similar skepticism regarding the unhinged use of frequency-domain methods to infer data and information about the time-domain behaviour of electromagnetic waves, e.g., see the recent book [16] and the papers [17][18][19][20]. ...

Radiation of Nonsinusoidal Electromagnetic Waves
  • Citing Article
  • January 1990

... In conclusion, we note that for a more detailed management of the information security of the digital economy at the micro and macro levels, it is necessary to use a more detailed description of the set of paths W. In particular, it is necessary to use the apparatus of the theory of homotopy and homology [5 -8], as well as multidimensional classifications for discrete networks [9]. This is necessary due to the fact that during the transition to macroeconomics, it becomes necessary to take into account the interaction of areas of influence with each other, as well as differences in education at different nodes of the social network. ...

Information Theory Applied to Space-Time Physics
  • Citing Book
  • January 1992