WI-GTWY-9-xxx Wireless Gateway V1.18
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Line-of-sight paths are only necessary to obtain the maximum range. Obstructions will reduce
the range, however may not prevent a reliable path. A larger amount of obstruction can be
tolerated for shorter distances. For very short distances, it is possible to mount the antennas
inside buildings. An obstructed path requires testing to determine if the path will be reliable -
refer the section 6 of this manual.
Longer distances can be achieved using the licensed 105U units, because they use a lower
frequency and licensed conditions generally allow a higher RF power to be used.
Where it is not possible to achieve reliable communications between two modules, then another
WI-I/O 9-x or WI-GTWY-9-xxx module may be used to receive the message and re-transmit it.
This module is referred to as a repeater.
An antenna should be connected to the module via 50 ohm coaxial cable (eg RG58, RG213 or
Cellfoil) terminated with a male SMA coaxial connector. The higher the antenna is mounted, the
greater the transmission range will be, however as the length of coaxial cable increases so do
cable losses. For use on unlicensed frequency channels, there are several types of antennas
suitable for use. It is important antenna are chosen carefully to avoid contravening the maximum
power limit on the unlicensed channel - if in doubt refer to an authorized service provider.
The net gain of an antenna/cable configuration is the gain of the antenna (in dBi) less the loss in
the coaxial cable (in dB).
The maximum net gain of the antenna/cable configuration permitted is
Country
Max. gain (dB)
USA / Canada
6
Australia / New Zealand
0
The gains and losses of typical antennas are
Antenna Gain (dB)
Weidmuller Part Nos.
Dipole with integral 15’ cable
0
WI-ANT-DPL-0-16
5dBi Collinear (3dBd)
5
WI-ANT-COL-5-32
8dBi Collinear (6dBd)
8
WI-ANT-COL-8-54
6 element Yagi
10
WI-ANT-YGI-10-6
16 element Yagi
15
WI-ANT-YGI-15-16
Cable type Loss (dB per 30 ft / 10 m)
RG58
-5
RG213
-2.5
Cellfoil
-3
WI-CCSMA-N-33 (33’ or 10m)
Cellfoil
-6
WI-CCSMA-N-66 (66’ or 20m)
The net gain of the antenna/cable configuration is determined by adding the antenna gain and the
cable loss. For example, a 6 element Yagi with 66 feet (20 meters) of Cellfoil has a net gain of
4dB (10dB – 6dB).