User Manual

Table Of Contents
Optical Master Unit
PRODUCT DESCRIPTION AND USER’S MANUAL
© Axell Wireless Ltd A1829300 rev H 30 (86)
Node detailes: number,
ID, Model
Node name
Node status
Select a node by clicking on
. The RMC will connect to the selected node.
The OMU unit polls the connected repeaters / nodes regularly and keeps control of login requests. If a user at a
repeater site wants to log in to the system, the OMU Control Module is responsible for granting / denying the
login request. If a user forgets to log out from the node when a session is finished, the system will automatically
log the user out after a configurable number of minutes of inactivity.
3.3 Fibre Loss Compensation and Master Volume
The OMU has a master attenuation that can be set in downlink (DL) and uplink (UL) separately. This
attenuation is useful for balancing of the whole system. See section
4.9 Balance the System for more
information about this feature.
Each fibre optic link in the system will induce a loss. This loss will also differ in magnitude from one link to
another since the distances between each repeater and the OMU is different. The Axell Wireless OMU-repeater
system can automatically calculate this loss, compensate for the loss in each link and by that also balance the
system.
This is accomplished by using a pilot tone of a well defined level which is sent from the master node to the
slave and vice versa. The received level of the pilot tone is measured and the loss is calculated. The Fibre Optic
Converter is automatically adjusted to compensate for the loss. The adjustment is made towards a target value
which means that the system will be balanced, i.e. all fibers will appear to have the same loss. The maximum
compensation is 10dB which equals an unbroken fibre distance of 20 km. For each connection in the link (for
instance at the ODF) approximately 0.5 dB of loss will have to be added.
The loss compensation function is activated as the system is set up. Please see section
4.8 Set Up OMU-
Repeater System. Each time the system has been changed or fibres have been exchanged or moved for some
reason, it is recommended to re-activate this function.
Note!
If the OMU is connected to repeaters of an earlier
release that has a fibre optic convert of the type in
the photograph, the Fibre optic loss cannot be
measured with this command.