To better understand why there are two separate sets of points in the scene, note that a point array (CAD object) is used to create a uniformly spaced base set. The array object always preserves its grid topology as you move it around the scene. However, the transmitters or receivers associated with this point array object are elevated above the irregular terrain and no longer follow a strictly uniform grid. If you move the base set from its original position to a new location, the base points' topology will stay intact, while the associated transmitters or receivers will be redistributed above the terrain based on their new elevations.
[[File:prop_txrx1_tn.png|400px]] [[File:prop_txrx2_tn.png|400px]]
Figure 1: Transmitters and receivers adjusted above an uneven terrain and their associated base sets.
== Running A SBR Simulation ==