Reference no: EM132181604
Assignment - Waveguides
Waveguides are very long metallic tubes to guide the propagation of electromagnetic waves. The Maxwell's equations inside these waveguides can be written as:
![991_figure.png](https://secure.expertsmind.com/CMSImages/991_figure.png)
These equations lead to the wave equations (taking the time dependence to be harmonic e±iωt):
![2197_figure1.png](https://secure.expertsmind.com/CMSImages/2197_figure1.png)
What you need to do:
Assume that z-axis along the length (the direction of wave propagation) of the wave-guide.
Rectangular waveguides:
![1038_figure2.png](https://secure.expertsmind.com/CMSImages/1038_figure2.png)
Ex, Ey, Bx, By → Transverse components
Ez, Bz → Longitudinal components
To get all these six components, we need to solve Helmhotz equation six times (for each component) with their boundary conditions. But boundary conditions for all the transverse components are not usually readily known. So in practice, we solve for Ez and Bz and try to find the other 4 components in terms of Ez, Bz and their partial derivatives.
(1) You are required to derive expression for Ex, Ey, Bx and By in terms of Ez and Bz and their partial derivatives.
(2) Determine Ez(x, y, z) by solving the Helmhotz equation.
(3) The Transverse Electric (TE) mode:
In this mode, Ez = 0.
(a) Determine the 4 transverse components.
(b) Determine the minimum frequency that can be transmitted through a waveguide of width a.
(4) The Transverse Magnetic (TM) mode:
In this mode Bz = 0.
(a) Determine the minimum frequency components.
(b) Determine the minimum frequency that can be transmitted through a waveguide of width a.
(5) The Transverse Electromagnetic (TEM) mode:
In this mode, Ez = Bz = 0.
Show that, this mode is not possible in a waveguide with one surface. However, if the waveguide consists of two co-axial tubes, one inside the other, then, in principle, it is possible to have such a mode.
![949_figure3.png](https://secure.expertsmind.com/CMSImages/949_figure3.png)
Derive expressions Eρ, Bρ, Eφ and Bφ.
And find the minimum frequency that can be propagated through this waveguide.
Attachment:- Assignment File.rar