2-Port Insertion Loss Measurements - Agilent Technologies FieldFox N9912A User Manual

12. Remove the LOAD and leave the end of the cable to be tested open.
13. Press
14. Use Averaging to remove random noise from high-loss measurements. Press
The displayed trace shows the Cable Loss values in one direction through the
cable. A Return Loss measurement would show the loss for both down the cable
and back. Therefore, a Cable Loss measurement is the same as a Return Loss
measurement divided by 2.
The average Cable Loss across the specified frequency range is shown on the
screen below the graticules.

2-Port Insertion Loss Measurements

A 2-port Insertion Loss measurement, available with option 110, is used to
measure the loss through a DUT (device under test) – or cable – over a specified
frequency range. The FieldFox signal source is transmitted out the RF OUT
connector, through the DUT, and into the RF IN connector. Both ends of the DUT
must be connected to the FieldFox, either directly or indirectly using the cable
used in the normalization cal.
„Insertion‟ loss simply means loss through a device, usually expressed in dB. It is
exactly the same measurement as "S21 Transmission" in NA Mode.
2-port Insertion Loss measurements are generally more accurate than 1-port
Cable Loss measurements.
NOTE A Normalization Cal is REQUIRED for making accurate 2-port CAT or NA
measurements. Learn how on page 53.
For highest accuracy, when measuring the DUT also attach any cable or adapter
that was used in the normalization cal.
How to make a 2-port Insertion Loss Measurement
1. Press Mode then CAT.
2. Then
3. Press Freq/Dist and enter
4. Press Sweep 3, then select a
5. Press Cal 5, then press Normalization. Perform normalization as explained
6. Connect the DUT and view the insertion loss measurement results.
When measuring very long lengths of cable, it may be necessary to increase the
sweep time. Learn how on page 24. Learn why in the Supplemental Online
Help:
CAT (Cable and Antenna Test) Mode
Data –
then
Data Math
removed. These minor imperfections in the cable should not be considered in
the Cable Loss measurement.
BW 2 then Average.
More then Insertion Loss (2-Port)
measurement.
on page 53.
http://na.tm.agilent.com/fieldfox/help/
Mem. The ripple in the measurement is
.
and frequency values of the
Start Stop
setting.
Resolution
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