7
Installation
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7.7.11 Aligning the PTP 500 Series Bridge ODUs
The following is a description of the steps taken to establish a radio link between the two
units forming the bridge and align the units for the best signal strength.
The PTP 500 Series Bridge uses audible tones during installation to assist the installer with
alignment. The installer should adjust the alignment of the ODU in both azimuth and elevation
until highest pitch tone is achieved
. The tones and their meanings are as follows:
State Name
Tone
Description
State Description
Pitch Indication (Higher
pitch = higher power)
Free Channel
Search
Regular beep Executing band scan
N/A
Scanning Slow
broken
tone
Not demodulating the wanted
signal
Rx Power
Synchronized Fast
broken
tone
Demodulating the wanted
signal. Note: During
acquisition there may be
cycling between Scanning
and Synchronized states until
the alignment is sufficient to
maintain the link up.
Rx Power
Registered
Solid tone
Both Master and Slave units
exchanging Radio layer MAC
management messages
Rx Power
Table 13 - Audio indications from the ODU
The term ‘wanted signal’ refers to that of the peer unit being installed.
In each of the states detailed above, the unit should be aligned to give the highest pitch tone.
It should be noted that if, when in the Synchronized or Registered state, the tone varies
wildly, you may be suffering from interference or a fast fading link. Installing in this situation
may not give a reliable link. The cause of the problem should be investigated.
5
The pitch of the alignment tone is proportional to the received power of the wireless signals. The best results
are usually achieved by making small incremental movement in angular alignment.