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1answer
90 views

Can one make a propagating field along a waveguide only have longitudinal/transverse components?

We know that in free space, a propagating electromagnetic wave is always transverse. However, along a dielectric waveguide, the propagating wave can have longitudinal components. The exist of the ...
0answers
41 views

What is the meaning of the Fourier Transform of the electric field of a well guided mode in a dielectric waveguide?

I have been studying waveguiding in dielectrics for a while now; however, I cannot understand the meaning of the Fourier transformed electric field. I will first give some background information. ...
0answers
187 views

Why is Erbium Doped Fiber Amplifier (EDFA) preferred over Erbium Doped Waveguide Amplifier (EDWA)?

Why is Erbium Doped Fiber Amplifier (EDFA) preferred over Erbium Doped Waveguide Amplifier (EDWA)? The question has been asked from an engineering point of view, but obviously I would also be ...
0answers
19 views

Increase Phase Velocity by Losing Power

I just read some words from the book Optical Waveguide Theory by Snyder, Allan W., p226. It says that However, although it is possible for the phase velocity of a mode to exceed the maximum speed ...
0answers
100 views

Distance between minima's of standing wave in a wave guide

I just started studying waveguides, i have a basic doubt about the standing wave pattern in waveguide. How are the m,n values related to the distance between the minima's? I read in a book that , ...
0answers
58 views

Computing the Electric and Magnetic Field Distribution of a Funnel Waveguide

In our undergraduate E&MWaves class, we learned about a rectangular waveguide, and how to calculate the electric and magnetic field distribution throughout the waveguide using finite element ...
0answers
126 views

Longitudinal EMAG wave?

I'm reading about optical waveguide analysis, and often come across the terms "transverse electric mode" vs. "transverse magnetic mode". As I unerstand, it means that the electric/magnetic field has ...
0answers
14 views

Do Conch shell horns produce infrasound?

I was just reading an article about some guys at Stanford playing with ancient conch shell horns: http://news.stanford.edu/news/2011/february/conch-acoustic-musicians-020711.html They mention feeling ...
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19 views

Ultrasound in hollow tube

Ultrasound in pulse-echo mode (reflection from air-water interface) is used to measure the level in a tank filled with water. Since the level is several meters, a hollow steel tube is used to ...
0answers
7 views

trouble calculating dispersion curve for TE Mode symmetrical step-index waveguides

I'm trying to work on a problem where I'm needing to show the dispersion curves for a slab waveguide. I'm given the refactive index of the core, $n_1$, the refractive index of the cladding, $n_2$, the ...
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11 views

Reflection coefficient of transition coaxial and wave guide

Suppose you have a 1 GHz generator connected to a wave guide with a coaxial cable with a characteristic impedance of $Z_c =45 \Omega$. The wave guide is connected to the system which has a reflection ...
0answers
6 views

how do hybrid plasmonic waveguides work?

I was hoping that someone could clarify the operation of hybrid plasmonic waveguides for me. what I read on wikipedia left me with some questions: If the operation is based on coupling the ...
0answers
28 views

Why are photonics fibers called band gap fiber?

Why are photonics fibers called band gap fibers? Do the photonic fibers guide light inside the band gap or outside? What creates the band structure?
0answers
36 views

Why you need at least two conductors for Transverse electromagnetic (TEM) propagation in a waveguide?

Do the two conductors have to be separated (no current flowing) or 2 connected lines? Of course both connected to a generator? Thinking about the Maxwell equations I guess the 2 conductors are ...
0answers
57 views

phase velocity in dielectric lined waveguide

I want to simply calculate the phase velocity of a mode in a dielectric loaded waveguide but am having difficulty arriving at a sensible answer. Here I consider only a TM mode. The problem is ...
0answers
78 views

Transverse electromagnetic (TEM) mode waveguide

Suppose we have a parallel plate waveguide operating solely in the TEM mode, composed of perfect conductors. I understand that the electric field must terminate perpendicularly on the plates, where a ...
0answers
76 views

Wave propagation in micro strip waveguide

I am trying to understand wave propagation in micro-strip waveguide, the way i came to understand rectangular waveguide is this way (in brief): EM waves can be understood as reflecting from the ...
0answers
75 views

calculate the length and width a of waveguide for a span of frequency

I know how to calculate the length and width of a rectangular waveguide when the cut off frequency is given. But when a span of frequency is given how do we calculate it? Here what is given by a span ...
0answers
42 views

Dispersion relation in wave guides

I am reading Griffiths section 9.5. Assume that wave guides are surrounded by perfect conductors, and geometry is $z$-independent, as in the text. I understand he proved that in a hollow wave guide, ...
0answers
210 views

How can electric and magnetic fields have any component in the direction of propagation of electromagnetic waves?

In case of waveguides we talk about $E$ and $H$ having non zero component in the direction of propagation of wave. But the entire basis of EMW is that $E$ and $H$ are perpendicular to the direction of ...
0answers
56 views

Non reflecting boundaries in waveguides

Can someone please explain the Sommerfeld radiation condition and what is the alternative non-reflecting boundary conditions for waveguides of general geometries?