User's Manual

3CC12425AAAA TQ BJA 01 Issue 01 - April 2001 - Draft 03 39/70

27. If vertical, fine align the X-Pol RT antenna to maximum field strength using the spectrum analyzer

and record the level. If this recorded level is already 15 dB below the calculated RSL, natural

misalignment due to the elevation relationship between the BS and TS has occurred and no further

misalignment is necessary. Proceed to «29».

28. If the measured RSL is not 15 dB below the calculated RSL, misalign the X-Pol RT antenna upwards

in the vertical plane until the RSL is 15 dB below the calculated RSL and record the value.

29. Tighten the pole elevation and azimuth bolts to 4.1 Nm (36 in-lb) torque, and the vertical angle bolts

to 10.85 Nm (8 ft-lb) torque.

30. Verify the level measurement using the spectrum analyzer to ensure that the X-Pol RT is still aligned

to the desired level in «28». If this level has changed, repeat «27-29».

31. Switch the NT off, disconnect the test equipment and reconnect the IF cable to the NT. Switch the

NT on.

32. In the case where the desired sector’s X-Pol RBS Tx/X-Pol RBS Rx pair is horizontally separated by

∼ 10 meters worst case, in order for an equivalent amount of CPE antenna gain to be seen by both

the X-Pol RBS Tx and the X-Pol RBS Rx, the CPE should be aligned to the mid point between the

X-Pol RBS Tx and X-Pol RBS Rx. This task can be performed visually within a few hundred meters

where the worst case at 100 m would yield ∼ 16 dB of CPE misalignment to both the X-Pol RBS Tx

and X-Pol RBS Rx respectively. In this case, no elevation misalignment is necessary. As we

approach the AMTR (distance depends on rain region), visual alignment to the mid-point of the X-

Pol RBS Tx and X-Pol RBS Rx becomes more difficult but is not as critical whereby if the CPE were

aligned to the X-Pol RBS Tx instead of the mid-point, the X-Pol RBS Tx would only have ∼ 1 dB

stronger relative antenna impact to the X-Pol RBS Rx, which is acceptable.

33. Record this azimuthal mid-point RSL. If this recorded level is already 15 dB below the calculated

RSL, natural misalignment due to the mid-point TS antenna pattern roll-off and/or the elevation

relationship between the BS and TS has occurred and no further misalignment is necessary.

Proceed to «35».

34. If the measured RSL is not 15 dB below the calculated RSL, misalign the X-Pol RT antenna upwards

in the vertical plane until the RSL is 15 dB below the calculated RSL and record the value.

35. Tighten the pole elevation and azimuth bolts to 4.1 Nm (36 in-lb) torque, and the vertical angle bolts

to 10.85 Nm (8 ft-lb) torque.

36. Verify the level measurement using the spectrum analyzer to ensure that the X-Pol RT is still aligned

to the desired level in «34». If this level has changed, repeat «33-35».

37. Switch the NT off, disconnect the test equipment and reconnect the IF cable to the NT. Switch the

NT on.

4.2 – Commissioning the NT

Note: To carry out the following phases of the Terminal Station commissioning, the link Base Station

must be operational and its antenna correctly orientated.

Considerations

– Before commissioning the NT unit, complete the X-Pol RT unit adjustment procedures.

– No adjustment is required for commissioning the NT.

– To check the voltage at the mains connector terminals, use a measuring instrument (voltmeter).

1. Please note that Alcatel recommends the use of a vertical X-Pol RBS Tx/X-Pol RBS Rx configu-

ration wherever possible.