Cambium PTP 450 series, Руководство пользователя

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PTP 450 User Guide Selecting Sites for Network Elements
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ptp-450 (July 2014)
To use the Frame Calculator to ensure that all BHMs are configured to transmit and receive at the same time, follow
the below procedure:
Procedure 4 Using the Frame Calculator
1
Populate the OFDM Frame Calculator parameters with appropriate values as described
above.
2
Click the Calculate button.
3
Scroll down the tab to the Calculated Frame Results section
4
Record the value of the BHM Receive Start field
5
Enter a parameter set from another BHM in the system – for example, an BHM in the
same cluster that has a higher Max Range value configured.
6
Click the Calculate button.
7
Scroll down the tab to the Calculated Frame Results section
8
If the recorded values of the BHM Receive Start fields are within 150 bit times of each
other, skip to step 10.
9
If the recorded values of the BHM Receive Start fields are not within 150 bit times of
each other, modify the Downlink Data parameter until the calculated results for BHM
Receive Start are within 300 bit time of each other, if possible, 150 bit time.
10
Access the Radio tab in the Configuration web page of each BHM in the cluster and
change its Downlink Data parameter (percentage) to the last value that was used in the
Frame Calculator.
Selecting Sites for Network Elements
The BHMs must be positioned

with hardware that the wind and ambient vibrations cannot flex or move.

where a tower or rooftop is available or can be erected.

where a grounding system is available.

with lightning arrestors to transport lightning strikes away from equipment.

at a proper height:
o
higher than the tallest points of objects immediately around them (such as trees, buildings, and tower legs).
o
at least 2 feet (0.6 meters) below the tallest point on the tower, pole, or roof (for lightning protection).

away from high-RF energy sites (such as AM or FM stations, high-powered antennas, and live AM radio
towers).

in line-of-sight paths
o
to the BHSs.
o
that is not obstructed by trees as they grow or structures that are later built.
Visual line of sight does not guarantee radio line of sight.