Spherical Modes

This option defines an ideal receiving antenna with spherical modes.

Parameters:

Request name: The name of the request.
Mode data source: The spherical modes can be entered directly in the .pre file or it can be imported from a TICRA (.sph) file.
Position (coordinate): The coordinates of the origin r = 0 of the mode in metres. These values are optionally scaled by the SF card.
Rotation about the axes: The rotation of the spherical mode source about the X, Y and Z axes.
Number of modes: Specify the number of modes that will be entered in the .pre file.
Traditional index (smn): If this option is selected, you can specify TE-mode (s = 1) or TM-mode (s = 2) and the indices m and n in the group below. Here n is the mode index in the radial direction and must be in the range 1, 2, . . . $\infty$ and m is the mode index in the azimuth direction $φ$ . There is no distinction between even and odd modes (with $\cos (m φ)$ and $\sin (m φ)$ angular dependencies), but rather use the angular dependency $e^{j m φ}$ . Thus the index m can also be negative, but it must be in the range -n . . . n.
Compressed index (j): With this option, a compressed one-dimensional mode numbering scheme is used. The Mode index j is then specified as
(1) $j = 2 [n (n + 1) + m - 1] + s$
where s = 1 for TE-mode and s = 2 for TM-mode. This unified mode numbering scheme allows the computation of an extended scattering matrix (with network and radiation ports). This index j then represents a unique port number in the scattering matrix.
Magnitude of the mode in $\sqrt{W}$: Absolute value of the complex amplitude of this specific spherical mode (due to the applied normalisation of the spherical modes, the unit of this amplitude is $\sqrt{W}$ = $\sqrt{V A}$ ).
Phase of the mode (degrees): The phase of the complex amplitude of this spherical mode in degrees.
Use all data blocks: Import all data blocks from the specified TICRA (.sph) file. The data is interpolated for use at the operating frequency.
Use only specified data block number: Use the data from the nth frequency block in the TICRA (.sph) file.