For this lab exercise, I am providing a Matlab File that plots the z = 0 (x,y) plane distribution of the Hmn (TE) fields (surface plot of H and vector plot of E).
You will:
1. Change the values of (m,n) and describe what you see. Is this what you expected? Why or why not?
2. Edit the file so that it also generates the (xz) or (yz) projections of the H and E fields. What do you observe? Is this what you expected?
3. Add calculations of the critical wavelength (plot with respect to m and n), the fundamental mode and the highest order mode that your waveguide will support (plot with respect to the signal frequency, omega).
4. Also plot:
(a) the phase constant (beta) as a function of the signal frequency and a nominal (choose one of the values you calculated above) cutoff frequency.
(b) the intrinsic wave impedance (eta_TE) as a function of the signal frequency and a nominal (choose one of the values you calculated above) cutoff frequency.
(c) the phase velocity and the group velocity of the wave as a function of frequency. What do you notice regarding the values of the phase and group velocities with respect to the velocity of the signal in the corresponding non-guided dielectric?
5. Assume lossy dielectric (sigma). Repeat steps (1)-(4) for the case of a lossy dielectric (add to the current Matlab file in such a way as setting sigma=0 gives you the lossless case)
6. Create a new file (you can use the original file as a template) and repeat parts (1) through (5) for the TM fields for various choices of m,n.
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