=== Defining Transmitter Sets ===
[[File:PROP20(1).png|thumb|400px|EM.Terrano's Transmitter dialog with a user defined pattern selected.]]
A transmitter is a point radiator with a fully defined polarimetric radiation pattern over the entire 3D space in the spherical coordinate system. You can model a radiating structure using [[EM.Tempo|EM.TEmpo]], [[EM.Picasso]], [[EM.Libera]] or [[EM.Illumina]] and generate a 3D radiation pattern data file for it. These data are stored in a specially formatted file with a "'''.RAD'''" file extension. It contains columns of spherical φ and θ angles as well as the real and imaginary parts of the complex-valued far field components '''E<sub>θ</sub>''' and '''E<sub>φ</sub>'''. The θ- and φ-components of the far-zone electric field determine the polarization of the transmitting radiator.
<table>
<tr>
<td> [[File:PROP20(1).png|thumb|400px|EM.Terrano's Transmitter dialog with a user defined pattern selected.]] </td>
<td> [[File:PROP20A.png|thumb|600px|EM.Terrano's Transmitter Chain dialog.]] </td>
</tr>
[[File:PROP21(1).png|thumb|400px|EM.Terrano's preliminary Receiver dialog.]]
[[File:PROP22.png|thumb|400px|EM.Terrano's Receiver dialog with an isotropic radiator selected.]] Receivers act as observables in a propagation scene. The objective of a SBR simulation is to calculate the far-zone electric fields and the total received power at the location of a receiver. In that sense, receivers indeed act as field observation points. You need to define at least one receiver in the scene before you can run a SBR simulation. You define the receivers of your scene by associating them with the base sets you have already defined in the project workspace. Unlike transmitters that usually one or few, a typical propagation scene may involve a large number of receivers. To generate a wireless coverage map, you need to define an array of points as your base set.
To define a receiver observable in EM.Terrano, follow the procedure below:
<table>
<tr>
<td> [[File:PROP22.png|thumb|400px|EM.Terrano's Receiver dialog with an isotropic radiator selected.]] </td>
<td> [[File:PROP22A.png|thumb|600px|EM.Terrano's Receiver Chain dialog.]] </td>
</tr>