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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 ...
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1answer
31 views

Coaxial waveguide - wave impedance

Determine the capacity $C$ per $m$, the inductance $L$ per m and the wave impedance $Z_0$ for a coaxial waveguide with inner radius $a$ and outer radius $b$. How large would $b$ have to be so ...
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1answer
48 views

Cantenna and waveguide

I'm studying for a lecture of RF and wave guides and i'm currently building a cantenna. I have two questions about it construction and on how it works. My questions are about the lengths of the ...
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1answer
33 views

Wave guide boundary conditions

Why only the normal component of Electric field and the parallel component of Magnetic field exist at the surface of a wave guide or any conductor?
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3answers
178 views

Why is signal bad in a tunnel?

Consider this: you are driving through a tunnel listening to your AM radio and a GPS, all of the sudden AM radio has nothing but statics and your GPS says "reconnecting - please hold". You say to ...
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21 views

Waveguide: Geometric interpretation to the $\sqrt{(1 - (f_{mn} /f)^2)}$ factor that appears everywhere?

In EM pretty much everything has a greek alphabet associated with it, that's why I'm got a bit curious while looking at the $\sqrt{(1 - (f_{mn} /f)^2)}$ factor which appears everywhere in wave guide ...
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1answer
104 views

Can someone prove that the $\tilde{E}$ and $\tilde{H}$ fields in a waveguide looks as pictured?

Hi, I'm trying to use the solution to the wave's equation in a rectangular waveguide for $\tilde{E}$ and $\tilde{H}$ to show how I can get the above picture. For example, why is the magnetic field ...
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0answers
34 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 , ...
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2answers
351 views

EmDrive Cavity modes

The EMDrive described in patent application GB 2493361 is a simple section of a sphere surrounded by a superconducting cooling system. I have attempted to solve the oscillation modes possible and ...
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1answer
358 views

Wavelength and Frustum shaped resonant cavity

Given a right conical frustum resonator top radius r, bottom radius R and height h, what is the relationship of the wavelength w that we wish to create resonance with, to r, R, and h? Assume for now ...
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1answer
31 views

How to block coupling between adjacent waveguides?

I have a number of nonlinear waveguides, say six. I don't want coupling between specific two waveguides. Other than keeping them large distance away, what are the other possibilities to ensure no ...
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1answer
284 views

Total internal reflection and waveguides

I'm looking at a model of a planar dielectric waveguide along the lines of this picture: For the wave inside the $n_1$ dielectric slab to totally internally reflect $\theta_M$ needs to be smaller ...
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1answer
37 views

Optical Waveguides with grating

I have some problems about mode analysis in grating-coupled waveguides,Would you please introduce me a useful book about wave propagation in these structures.
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1answer
214 views

Reconciling total internal reflection and the evanescent Wave

I understand that light is guided in a dielectric waveguide via total internal reflection. My question is regarding the origin of power contained in the evanescent field traveling along the direction ...
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0answers
53 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 ...
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1answer
157 views

Waveguides Transmission Mode Determination

How do I know if I have TE, TM, or TEM rectangular conductive waveguide? For instance, I am doing a lab where we want maximum magnetic field in the waveguide, does that mean we want the TE because ...
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1answer
297 views

Optical Waveguide's “Base Bandwidth”

Consider a dielectric slab waveguide (lossless, isotropic) illuminated transversally from the vacuum (with coherent, monochromatic light). We define the base bandwidth of a waveguide (or optical ...
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3answers
656 views

Waveguides and Maxwell's Equations

Background In many textbooks on electromagnetism, the sequence in which topics are introduced are generally as follows -- electrostatics, magnetostatics, electrodynamics, wave propagation in free ...
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2answers
217 views

Fiber optics with broadband, incoherent light

I wonder if someone could help clarify waveguiding with broadband, incoherent light please. If we take a telecomms fiber, which is single-moded above ~1.4 μm and couple a laser beam in, we assume ...
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0answers
142 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 ...
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0answers
112 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 ...
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1answer
388 views

Electric Field in Circular waveguide in TE mode

I know that the magnetic field inside a circular waveguide is $B_z=B_0\dfrac{\rho}{R}\left(1-\dfrac{\rho}{2R}\right)\cos{\phi}\sin{\frac{\pi z}{d}}$ How can I find the two components of the electric ...
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3answers
241 views

Waveguides (in the ocean?)

The speed of sound in the ocean is given by $$c_s(\theta,z) = 1450 + 4.6\theta - 0.055\theta^2 + 0.016z$$ $\theta$ is the temperature in degrees celcius, and $z$ is the depth. In a simplified model, ...
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52 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?
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1answer
3k views

Plane wave expansion in cylindrical coordinates

I am trying to solve scattering problem in 2D and got to expand the wave function in cylindrical system which comes out to be Hankel function. Can you tell me how to expand the plane wave $\exp(i ...
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1answer
161 views

Optical waveguide that can displace a 4D light field

Has anyone invented an optical waveguide that can "pipe" a scene from one place to another unaltered? More precisely, I want to displace (and/or rotate) a 4D light field. An optical waveguide is an ...
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1answer
146 views

Is the acceleration and deceleration of a wave instantanious?

When an light travels in free space, it has a velocity of propagation equal to the speed of light. However, then the light enters a medium with a refractive index of n, the velocity of propagation ...
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4answers
4k views

What is magnetic conductivity?

I searched google for the meaning of magnetic conductivity but couldn't figure out what is it? electric conductivity is usually means that there is the electric field parallel to the interface is ...
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3answers
4k views

Is the EmDrive, or “Relativity Drive” possible?

In 2006, New Scientist magazine published an article titled Relativity drive: The end of wings and wheels1 [1] about the EmDrive [Wikipedia] which stirred up a fair degree of controversy and some ...