Antennas
There is no single antenna that is perfect for all
applications. Therefore, a variety of antennas are offered, as shown in Figure
. The customer
will usually dictate antenna choice and placement. A customer may not want the
antenna to be visible, or it may be located in a high traffic area. The minimum
collection of antennas should include the following:
- 2.2 dBi Dipole Antenna "rubber ducky"
- 2.0 dBi Diversity Omni Ceiling Mount Antenna
- 5.2 dBi Pillar- Mount Diversity Omni Antenna
- 6.0 dBi Diversity Patch Wall Mount Antenna
- 8.5 dBi Hemispherical Patch Antenna
- 13.5 dBi Yagi Mast Mount Antenna
Other antennas may also be used.
Always survey with the intended
antenna. If diversity is planned, then two of every antenna will be needed. Do
not use a different antenna and attempt to guess the coverage that is needed.
The site survey is performed in order to take the guesswork out of the
installation.
Antenna Attenuator
Surveys should always be
performed using the equipment that will eventually be installed. This can
sometimes be difficult with splitters, lightning arrestors, and extension
cables.
Instead of carrying every length of cable, lightning arrestors,
splitters, and other accessories, some engineers outfit the site survey kit
with an antenna attenuator. The antenna attenuator allows loss to be injected
without needing the actual accessories. For instance, if there will be a 100
feet of cable with splitters run during the actual install, the signal loss can
be simulated by the attenuator. This can save a site engineer valuable time and
money.