Matlab program to plot the time-variant electric field intensity |E(t)| in the plane for single-frequency excitation over a few sinusoidal cycles. This
problem will help you visualize how the dipole antenna operates.
We will be able to see two distinct regions: a near-field region where fields are dominated by stored energy (fields do not propagate outward) and a far-field region where fields propagate out.
The calculation of angle \theta is not correct. It should be acos(z/r). Also I guess the author meant wave impedance for \eta, then the value should be approximately 120*pi, not 200*pi. The frequency should be found through \lambdda, instead of being specified arbitrarily.