User's Manual

3CC12426AAAA TQ BJA 01 Issue 01 - April 2001 - Draft 04 97/346
104
5. Measure the losses at the lowest and highest frequencies in the frequency band used by the system.
1. Set the signal generator frequency to the Llow frequency and the RF output power level to
0dBm.
2. Connect the signal generator to the appropriate SMA cable (IBS-TLX). Connect the power meter
to the X-Pol RBS Tx/X-Pol RBS Rx IF cable. Figure 82 shows the test setup.
3. Measure the RF power level with the power meter. Record this value as the upstream or
downstream L
low
value.
4. Repeat this step at the L
hi
frequency.
6. Use the equation below to calculate the mean attenuation. Record the result as the downstream or
upstream L
A nom
value.
L
A nom
= ((L
low
+ L
hi
)/2)
where
LA nom represents the required attenuation value (nominal)
Llow represents the loss measurement at the lowest frequency
Lhi represents the loss measurement at the highest frequency
LR represents the required loss value (27 dB ±1 dB for the downstream path, 24 ±1 dB for the ups-
tream path)
7. Enter in 7390LT radiolink intallation screen recorded attenuation value for downstream and
upstream cables.
8. Reconnect the SMA and IF cables.
9. Reconnect the Bias-T power cables.
10. Reapply the dc power.