WirelessHART Fieldgate SWG70, Руководство по эксплуатации

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WirelessHART Fieldgate SWG70 4 Mechanical Installation
Hauser 15
4.1.4 Antenna range
Fig. 4.2 is a schematic representation of Fig. 4.1 and shows the wave propagation with the signal
attenuation. The antenna is an omni-directional dipole antenna. If you point the antenna upwards,
the signal radiates horizontally at an angle of approx. 39 degrees above and below the horizontal
(donut shaped). The most power is in the horizontal plane, decreasing to 50% at an angle of 39°.
Almost no signal will be radiated directly above and below the antenna. Consider this when
planning a WirelessHART network.
The height differences between wireless devices in a network should not be too large.
The schematic is valid only for an antenna placed outdoors with no metal surfaces near. The
radiation pattern changes significantly when metal surfaces are close to the antenna.
Fig. 4-2: Wave propagation, schematic representation (alpha = approx. 39°)
1: No signal above and below 2: Stronger signal sideways
1
2 2
1
Į
Į
Į
Į
100%
100%
50% 50%
50% 50%
0%
0%