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Page 51
Chapter 6: Installation
Table 6-1. Distance.
Distance (km)
Master Height (m)
Remote Height (m)
Path Loss (dB)
5
15
2.5
116.5
5
30
2.5
110.9
8
15
2.5
124.1
8
15
5
117.7
8
15
10
105
161
15
2.5
135.3
16
15
5
128.9
16
30
10
116.2
16
30
10
109.6
16
30
5
122.4
16
30
2.5
128.8
Once the equipment is deployed, the average receive signal strength may be determined by accessing S Register 123.
6.2 Installation of Antenna System Components
Only qualified and experienced personnel should install, remove, or maintain any antenna system components.
6.2.1 Antennas
The two most common types of antenna are the omnidirectional (“omni”) and directional (Yagi).
An omni typically has 3–6 dBi gain and spreads its energy in all directions (hence the name “omnidirectional”). The “pattern” of
the energy field is in the shape of a donut, with the antenna mounted vertically at the center. This vertical-mounted antenna
produces a signal that is vertically “polarized.”
A Yagi has a more focused antenna pattern, which results in greater gain: commonly, 6–12 dBi. The pattern of a Yagi is in the
shape of a large raindrop in the direction in which the antenna is pointed. If the elements of the Yagi are perpendicular to the
ground (most common orientation) the radiated signal will be vertically polarized; if parallel to the ground, the polarization is
horizontal.
The network topology, application, and path calculation are all taken into consideration when selecting the various antenna types
to be used in a radio network deployment.
CAUTION: To satisfy FCC radio frequency (RF) exposure requirements for mobile transmitting devices, maintain a separation
distance of 23 cm or more between the antenna of this device and persons during device operation. To ensure
compliance, operation at less than this distance is not recommended. The antenna used for this transmitter must not
be co-located with any other antenna or transmitter.
CAUTION: Never work on an antenna system when there is lightning in the area.
WARNING: Direct human contact with the antenna is potentially unhealthy when a MDR100A-R5 or MDR112A-R5 is
generating RF energy. Always ensure that the equipment is powered down (off) duringinstallation.
In a long-range PTP network, consider using Yagi antennas. There antennas will provide for the most focused “RF
connection” between the two sites.
In a PMP network where Remotes are located in all directions from the Master, the Master site will have an omni so that it can
communicate with all Remotes; the Remotes, however, may all employ Yagi antennas “pointed at” the Master.
