Europlex 3GS, Руководство пользователя

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Nodes 5-38
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If the movement of the HUA node is not possible, attach the antenna to the HUA node via a 50 Ohm coaxial cable
<10m in length and locate the antenna at the point of maximum signal strength. This must be verified with the test
equipment.
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In cases where the above solutions are unsatisfactory, another HUA node will have to be fitted to provide
adequate coverage on site. Steps 1-3 can be followed to optimise the node performance if required.
RPA Install Test Procedure
Due to the vagaries of radio transmission, direct unit to unit comparison will give an unacceptably wide range of
performance values and cannot be used as a guideline for site installation. It is suggested that for new and retrofit
installations, a test RPA is provided which provides output at the lower range and a modified HUA test node along with
a HHT are used to ensure that adequate coverage is provided on each site.
Test Method
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Locate the test node at the required location of the HUA node.
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Setup the HHT to monitor the RPA signal strength.
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Try the test RPA unit at the test node to ensure correct operation and full signal strength.
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Remove the test RPA to the area to be tested and perform the test transmissions.
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Ensure that the signal strength for each test is a pass value (>40%) on the HHT.
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If a particular location fails to produce the pass signal, then the test node must be moved closer to the test point or
to a location where there are less obstructions on the path to the test point. Once the test node has been set up at
the new location, all the previous tests have to be redone to ensure they all still provide a pass signal value.
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The HUA node must then be mounted at the exact position of the test node to provide equal performance.
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The ringnet cables must be routed away from the antenna when installing the node.
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Test all RPAs that are to be assigned to the site at the test locations as per the test RPA unit and install them onto the
system as per the System Integration Manual.
It is recommended that the HUA node be mounted away from computers and large metal masses if possible (that is,
cable trays, filing cabinets, and metal shelves) as these objects tend to reduce the sensitivity of the receiver within the
HUA node.