Nera WiLink-I 3000, Системное руководство

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26 Installation
Chapter 2 - Installation Guidelines
cable at applicable frequencies, its screening effectiveness and its maximum
permitted DC resistance (the sum of the DC resistance of the inner and outer
conductors) are provided in
Table 2-2 .
To comply with the required screening effectiveness requirement, it is
recommended to use double shielded cables.
Table 2-3 provides details on
maximum length for some popular cables.
2.1.4 Pole Mounting the ODU
The ODU can be mounted on a 1" to 4" pole using one of the following options:
¢
Special clamps and threaded rods are supplied with each unit. There are two
pairs of threaded holes on the back of the unit, enabling to use the clamps for
mounting the unit on diverse pole diameters.
¢
The protrusions with grooves on the top backsides of the unit, and the
protrusion on the bottom backside, enable the use of 9/16" wide metal bands
(not included with the package) to secure the unit to a pole.
Table 2-2: IF Cables Requirements
Item Description
Screening Effectiveness 90 dB minimum in the 10-300 MHz band.
IF cable Impedance 50 ohm
Maximum IF cable Attenuation AU-ODU: 19 dB @ 240 MHz, 15 dB @ 140 MHz, 8 dB @ 64 MHz
AU-ODU-HP: 19 dB @ 240 MHz, 15 dB @ 140 MHz, 8 dB @ 64 MHz
Maximum IF cable DC Resistance AU-ODU:4.0 ohm
AU-ODU-HP: 1.5 ohm
Maximum IF cable Return Loss 20 dB in the 10-300 MHz band
Table 2-3: Maximum IF Cable Length (Double Shielded Cables)
Cable Maximum Length for AU-ODU Maximum Length for AU-ODU-HP
LMR-195 80 meters 30 meters
LMR-240 150 meters 60 meters
LMR-400 250 meters 150 meters
NOTE
Install the unit with the bottom panel, which includes the LEDs, facing downward.