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Use a multimeter to measure the RSL (P1) on the RSSI port of the horizontally polarized RFUs at the
local end.
Power on the vertically polarized RFUs at the local end. Use a multimeter to measure the RSL on the
RSSI port of the vertically polarized RFUs. Release the holder of the feed boom gently, and turn the feed
boom gently until the RSL reaches the minimum value (P2). The calculated XPD1 (XPD1 = P1 - P2)
cannot be less than 24 dB. Record the current angle (D1) of the feed boom.
Power off the horizontally polarized RFUs at both ends of the radio link, and power on the vertically
polarized RFUs at both ends of the radio link. Adjust the azimuth and elevation of the antennas at both
ends by referring to the description in “Aligning Single-Polarized Antennas”, and ensure that the main
lobes of the vertically polarized signals are aligned with the antennas.
Refer to Steps 3 and 4 to ensure that the calculated XPD2 (XPD2 = P3 - P4) is equal to or more than 24
dB. Record the current angle (D2) of the feed boom.
Repeat Steps 1 to 6 to adjust the feed boom gently (ranging from D1 to D2), and ensure that XPD1 and
XPD2 are equal to or more than 24 dB.
Tighten all the screws of the antennas after the alignment is completed.
Checking the Radio Link Status
LINK indicator
Check the status of the LINK indicator on the IF board.
If the LINK indicator is on (green), the radio link is functioning properly.
If the LINK indicator is on (red), check whether the configuration data is correct. If the configuration data is
incorrect, configure correct data.
If the LINK indicator blinks yellow at intervals of 300 ms, check whether the antennas are aligned properly. If the
antennas are not aligned properly, realign the antennas.
If the LINK indicator is off, check whether the logical units of the IF unit and the RFU/ODU have been added on the
NMS. If yes, check for a fault in the IF jumper, IF cable, or the RFU.
a
b
c
d
