User Manual

MBF, Multi Band Repeater

PRODUCT DESCRIPTION AND USER'S MANUAL

4.2.4 Node Access

An operator can login to the system from any node in the network and access all parameters in all nodes,

including those in the node master unit. This can be done using a serial cable connected to the node’s LMT-

port or by remote access over a modem in the master unit.

Select “System Nodes”

Node detailes: number,

ID, Model

Node name

Node status

Select a node by clicking on . The RMC will now 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.

4.3 Fibre Loss Compensation

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 also be balanced (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 will have to be added to the loss.

The loss compensation function is activated by some quick commands as the system is set up. 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.