Motorola MOTOWI 4 PTP 600 Series, Руководство пользователя системы

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The following behavior should be noted:
•
When first started up and from time to time, the Master unit will carry out a band scan to
determine which channels are not in use. During this time, between 10 and 15 seconds,
the Master unit will not transmit and as a consequence of this neither will the Slave unit.
During this time the installation tone on the master unit will drop back to the band scan
state, and the Slave unit will drop back to the Scanning state with the pitch of the tone set
to the background noise level. Alignment of the unit should cease during this time.
•
The master unit can take up to 60 seconds in 0-40km (0-25 miles) mode, 90 seconds in
0-130km (0-81 miles) mode and 120 seconds in 0-200km (0-124 miles) mode to
determine the range of the link being installed
11F
12
. The Master unit will remain in the
Scanning state until the range of the link has been established. The Master unit will only
move to the Synchronized state when the range of the link has been established.
•
If, at the end of the ranging period, the Registered state is not achieved due to
interference or other reasons, the Master unit will retry twice more on the same channel
before moving to another available channel. Should this occur it might take a number of
minutes to establish a link in the Registered state.
•
The Slave unit does not have a ranging process. The slave unit will change to the
Synchronized state as soon as the wanted signal is demodulated.
When the alignment process is complete the installer MUST REMEMBER TO DISARM BOTH
UNITS in the link as described in Section
1041H
8.3.4. This is necessary in order to:
•
Turn off the audible alignment aid
•
Enable Adaptive Modulation
•
Fully enable Advanced Spectrum Management with i-DFS
•
Clear unwanted installation information from the various systems statistics
•
Store the link range for fast link acquisition on link drop
•
Enable higher data rates
12
If the unit is operating where mandatory radar avoidance algorithms are implemented the ranging
behaviour for the PTP 600 Series Bridge may be affected. The Master has to monitor the initially
chosen channel for 60 seconds to make sure it is clear of radar signals before transmitting. If a radar
is detected during any of the installation phases a further compulsory 60 seconds channel scan will
take place as the master unit attempts to locate a new channel that is free of radar interference