Viavi CellAdvisor 5G, User Manual

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CellAdvisor 5G User's Guide
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b Tap the band to be measured.
3 Tap Link between Uplink and Downlink .
4 Tap Channel Number .
5 Enter a value by using the on-screen keyboard and tap Apply .
The CellAdvisor 5G automatically displays the corresponding center frequency value for the selected channel number.
Setting reference level
You can set the reference level automatically or manually to optimize the display of the traces measured, as you desire.
To automatically set the reference level:
1 Tap Amp/Scale under Menu ( ).
2 Tap Auto Scale .
Each time you tap, the Y-axis scale changes to be optimized with some margin.
To set the reference level manually:
1 Tap Amp/Scale under Menu ( ).
2 To set the maximum reference value on the Y-axis manually:
a Tap Reference Level
b Enter a value by using the on-screen keyboard and tap Apply .
Optional. To change the scale unit:
1 Select Scale Unit under Amp/Scale .
2 Select the unit of the display scale from: dBm , dBV , dBmV ,
dBμV
, V , or W .
The scale unit on the screen changes accordingly.
Setting scale per division
You can use the Scale Division feature to change the scale per division, representing the value of one division on the horizontal
scale. The default setting is 10 dB per division and the maximum value can be set up to 20 dB.
1 Tap Scale Division under Amp/Scale .
2 Enter a value between 1 and 20 by using the on-screen keyboard and tap Apply .
Setting external offset
You can turn the External Offset on and manually set the external offset value. An offset consists of a cable loss and a user offset,
and the measurement result shows the value reflecting both offset values. When the external offset value is set at 40 dB, the
measurement result compensates 40 dB.
1 Tap External Offset Mode to On under Amp/Scale .
2 Tap External Offset
3 Enter a value by using the on-screen keyboard and tap Apply .
4 To turn the external offset off, tap External Offset Mode to Off .
Enabling Auto leveling
It is normal that you see higher level of RSSI in CPRI spectrum than you have seen in RF spectrum because the digital signal has a
di
fferent gain level from RF’s. If you use the Auto Leveling feature and enter the Noise Figure (NF) for the system to be tested, the
instrument calculates an offset that compensates the digital gain of RRH and applies it to the spectrum automatically to displace the
level of spectrum to a known RSSI power even though its accuracy cannot be guaranteed. Offset calculation for Auto Leveling is
based on the following: