Handbook

Axell Wireless Limited
Technical Literature
MWAA Primary F/O Head End Documentation
BDA Shelf 60-214802
Document Number 60-214802HBK Issue No. 1 Date 23/07/2009 Page 11 of 23
4.3.1. Termination of Unused Ports
In the event that any RF ports are unused (available for future expansion) these ports must be kept
terminated with the load terminations supplied by Axell for that purpose
Ensure that connections are kept clean and are fully tightened.
4.4 Optical Connections
The optical input and output ports will be shown in the system drawings. The ports are supplied with a
green plastic cover, which must be removed prior to the connection of the fibre cable. Ensure that
transmitter and receiver fibre cable are identified to prevent misconnection. At the master site, the
fibre transmitters are in the downlink path with the receivers in the uplink. At the remote sites the fibre
transmitters are in the uplink with the receivers in the downlink.
Always ensure that connections are kept clean and are fully tightened.
4.5 Commissioning
Once all connections are made the equipment is ready for commissioning.
To commission the system the test equipment detailed in Section 5.2. will be required.
Using the system diagrams and the end-to-end test specification (supplied with the equipment), the
equipment should be tested to ensure correct operation. Typical RF levels that are not listed in the
end-to-end specification, such as input levels to the fibre transmitters are detailed in the maintenance
section of this manual.
On initial power up the system alarm indicators on the front door of the equipment should be checked.
A green LED on each unit with a power supply to it illuminates to indicate that the power supply is
connected to the unit A red LED illuminated indicates a fault in that particular unit that must be
investigated before proceeding with the commissioning.
In the event that any part of the system does not function correctly as expected, check all connections
to ensure that they are to the correct port, that the interconnecting cables are not faulty and that they
are tightened. The majority of commissioning difficulties arise from problems with the interconnecting
cables and connectors.
4.6 Antenna Installation & Gain Calculations
1) The equipment requires two antennas, one a highly directional Yagi or similar directed towards
the donor cell base station, and one a leaky feeder, omni-directional antenna or Yagi to cover
the area in which the mobiles are to be served.
2) The maximum gain at which the equipment can be set is limited by the isolation that can be
achieved between these two antennas. Therefore when the antennas have been installed,
inject a signal (at a known power level) into one of them and measure the signal level received
by the other antenna on a spectrum analyser. The isolation can then be calculated as the
difference between these two figures. The gain in each path of the equipment should be set at
least 10 dB below this figure, using attenuators as described below in paragraph 5.
3) Also measure the received signal from the donor cell at the input to the equipment (base port).
The gain of the equipment downlink path should be set such the donor site will not overload
the equipment amplifiers. It is recommended that the input level should be less than -50dBm
at the input of the equipment (Base Port). (This figure is assuming maximum gain, and may be
increased by the value of the attenuator fitted in the downlink path.)