Cambium Networks PMP 450d Series, Руководство пользователя

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Chapter 2: System hardware Installing a GPS receiver
Page 2-51
Installing a GPS receiver
To install a GPS receiver as the timing reference source, use the following procedures:
 Mounting the GPS receiver on page 2-52

Cabling the GPS Antenna on page 2-53
 Installing and connecting the GPS LPU on page 2-53
Caution
Prior to power-up of equipment, ensure that all cables are connected to the correct
interfaces of the CMM4 unit and the UGPS receiver module. Failure to do so may
result in damage to the equipment.
GPS receiver location
Mount the GPS receiver at a location that meets the following requirements:

It must be possible to protect the installation as described in Grounding and lightning
protection on page 3-8 .
 It must have an un-interrupted view of at least half of the southern (resp. northern) sky in the
northern (resp. southern) hemisphere. For a receiver mounted on a wall there must be no
other significant obstructions in the view of the sky.

It must be mounted at least 1 m (3 ft), preferably 2 m (6 ft), away from other GPS receiving
equipment.
 It must not be sited in the field of radiation of co-located radio communications equipment and
should be positioned at a distance of at least 3 m (10 ft) away.
Mount the UGPS receiver on the wall of the equipment building if there is a suitable location on
the wall that can meet these requirements.
Mounting the GPS receiver module on the equipment building
If mounting the GPS receiver on the equipment building ( Figure 39 ), select a position on the wall
that meets the following requirements:

It must be below the roof height of the equipment building or below the height of any roof-
mounted equipment (such as air conditioning plant).

It must be below the lightning air terminals.

It must not project more than 600mm (24 inches) from the wall of the building.
If these requirements cannot all be met, then the module must be mounted on a metal tower or
mast.