Antenna Alignment - NEC IPASOLINK 400 Installation And Provisioning

ANTENNA ALIGNMENT

The basic settings described in the previous chapters should be done before the antenna alignment.
Before the alignment some temporary settings are required for correct receive level indication.
ALIGNMENT SETTINGS
 If the element is already connected to the NMS server, set Maintenance on (Current Status top of
page). This will record in the logs that some maintenance operation is going on causing RX level
changes and alarms
 Under Equipment Setup -> Radio Configuration -> Setup verify that the reference modulation is set
QSPK
 Check that the power setting is manual: Equipment Setup -> Radio Configuration -> Setup -> TX
Power Control = "MTPC".
 Under Equipment Setup -> AMR Configuration set AMR to ("Non Operation").
 Set the maximum power under Provisioning -> Modem Function Setting -> TX Power Setting.
These settings have to be done at both ends of the hop before the alignment. Note that the local settings
affect the RX level measurement at the remote end. Remember to restore the correct settings after the
alignment.
Note: depending on the local regulations, the use of maximum power during the alignment may be
prohibited. In any case the risk of interference to another link is minimal, when the alignment is done
quickly. The victim receiver must experience a rare deep rain or multipath fade during the alignment in
order to cause problems and therefore increasing power for a short period of time should not cause any
problems to other hops.
RECEIVER LEVEL MEASUREMENT
The ODU has an F-type female connector for the level monitoring. The voltage is available at all times.
There is no setting to switch the voltage off or on.
A typical calibration curve is presented in Figure 49. Before climbing to the ODU it is wise to check the
target voltage level. E.g. -45 dBm equals about 2,8V.
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