Wall Mounting

For many building installations it may not be possible to install the antennas
above the penthouse or other structures for the building. Often it is necessary
to install the antennas onto the penthouse or water tank of an existing building. When installing antennas onto an existing structure,
rarely has the building architect factored into the potential installation of
antennas at the onset of the building design. Therefore, as shown in Figure
11-9, the building walls may meet one orientation needed for the system but
rarely all three for a three sector configuration.
Therefore, it is necessary to determine what the offset from the wall of
the building structure needs to be. Figure 11-10 illustrates the wall mounting
offset that is required to ensure proper orientation for each sector.
Figure 11-10 shows that in order to obtain the directionality of the sector,
a structure is installed that will meet that requirement. The method for
determining the wall offset is shown in the following equation.
a
d  sin (f)
where
f is the angle from wall
a is the distance from the wall
d
diversity separation for a two-branch system