Motorola MOTOWI 4, User Manual

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Site Planning
42
6 Site Planning
6.1 Site Selection Criteria
The following are guidelines for selecting the installation location of the ODU and PIDU Plus for
a PTP 500 Series Bridge.
6.1.1 ODU Site Selection
When selecting a site for the ODU the following should be taken into consideration:
•
It is not possible for people to stand or walk inadvertently in front of the antenna
•
Height and location to achieve the best radio path
•
Height in relation to other objects with regard to lightning strikes
•
Aesthetics and planning permission issues
•
Distance from the ODU and connected Network equipment (Maximum cable run from the ODU
to the connected equipment is 100m [330 ft])
•
Distance from the PIDU Plus to the ODU (Maximum cable run from the PIDU Plus to the
ODU is 300m [990 ft] when using the Fiber interface)
6.1.2 PTP 500 Series Bridge PIDU Plus Site Selection
When selecting a site for the PIDU Plus the following should be taken into consideration:
•
Availability of a mains electricity supply
•
Accessibility for viewing status indicators and pressing Recovery switch.
6.1.3 Path Loss Considerations
The path loss is the amount of attenuation the radio signal undergoes between the two ends of the
link. The path loss is the sum of the attenuation of the path if there were no obstacles in the way
(Free Space Path Loss), the attenuation caused by obstacles (Excess Path Loss) and a margin to
allow for possible fading of the radio signal (Fade Margin).
L
free_space
+ L
excess
+ L
fade
+ L
seasonal
< L
capability
(3)
Where
L
free_space
= Free Space Path Loss dB
L
excess
= Excess Path Loss dB
L
fade
= Fade Margin Required dB
L
seasonal
= Seasonal Fading dB
L
capability
= Equipment Capability dB