Coaxial Cable Considerations; Antenna Mounting Considerations; Table 5: Cable Types And Signal Loss (Db) - ABB AWIN GW100 User Manual

AN TE NN AS A ND CAB L ING
4.4.1

Coaxial cable considerations

The importance of using a low-loss antenna coaxial cable is often neglected during radio in-
stallation. Using the wrong cable can cause huge reductions in efficiency, and these losses
cannot be recovered with any amount of antenna gain or transmitter power.
For every 3 dB of coaxial cable loss, half the transmitter power will be lost before reaching the
antenna. The choice of coaxial cable to use depends on: 1) the length of cable required to
reach the antenna, 2) the amount of signal loss that can be tolerated, and 3) cost considera-
tions. For long-range transmission paths, where signal is likely to be weaker, a low-loss cable
type is recommended.
For a short-range system, or one that requires only a short antenna coaxial cable, a less effi-
cient cable may be acceptable and will cost far less than large diameter cable. Refer to
for values that allow judging the effectiveness of various cables at 2.4 GHz.
Cable type
RG-58
RG-213
PFP-240
PFP-400
PFP-500
PFP-600
4.4.2

Antenna mounting considerations

The antenna manufacturer's installation instructions must be strictly followed for proper op-
eration of a directional or omnidirectional antenna. Using proper mounting hardware and
bracket ensures a secure mounting arrangement with no pattern distortion or detuning of
the antenna. The following recommendations apply to all antenna installations:
– Mount the antenna in the clear, as far away as possible from obstructions such as build-
ings, metal objects, dense foliage, etc. Choose a location that provides a clear path in the
direction of the opposite antenna. If the antenna is co-located with another antenna
(other than second antenna connector on the same radio), try to get at least one foot ver-
tical (31cm) or one foot (31cm) horizontal separation between the two.
– Polarization of the antenna is important. Most systems use a vertically polarized omnidi-
rectional antenna at the master station. Therefore, the remote antennas must also be ver-
tically polarized (elements perpendicular to the horizon). Cross-polarization between sta-
tions can cause a signal loss of 20 dB or more.
– When installed indoors, the radio must be grounded through the DIN rail for DIN rail-
mount versions or using the ground lug on the wall-mount versions. A surge arrestor must
be used on the antenna for outdoor installations.
2 2

Table 5: Cable types and signal loss (dB)

2.4 GHz loss (dB/100 ft.)
25.01
12.51
12.76
6.68
5.41
4.37
WIR E L ES SH AR T S YST EM PL A NN ING
3BN P 102 9 12 C
Table 5