Plotting the Far Field Spectrum
Far-field frequency spectra are obtained when a simulation is performed by specifying a list of frequencies or a frequency sweep. For each frequency, the far-field is calculated at the several directions given by the zenith (Theta) and azimuth (Phi) angular ranges and at the distance specified in the Far-Field panel of the Setup tabsheet. Therefore, a fixed direction (Theta, Phi) must be chosen to plot the far-field versus frequency.
Go to Results > Plot Far-Field Spectrum in the main menu to plot the far-field spectrum. This command displays the Select Far-Field Point dialog box, Fig. 1, where the fixed Theta and Phi angles can be selected. After clicking the OK button, the AN-XY Chart > application will show the frequency spectrum of the total E-field, Fig. 2.
The linearly polarized field components, E-theta and E-phi, as well as the circularly polarized components, E-right and E-left, can be plotted in amplitude, phase, real and imaginary parts by choosing these options under Plot in the AN-XY Chart main menu.
The far-field spectrum for a selected far-field point can also be tabulated. Go to Results > List Far-Field Spectrum in the AN-SOF main menu to display the Select Far-Field Point dialog box, where a fixed Phi and Theta can be selected. Then, the list of the far-field components versus frequency will be shown, which can be plotted by clicking the Plot button, Fig. 3.