R&S CMW-KG8 Series, Руководство пользователя

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CDMA2000 Signaling
R&S
®
CMW-KG8xx/-KM8xx/-KS8xx
473 User Manual 1173.9511.02 ─ 11
4.2.5 External Fading
An external fading scenario allows to route the forward link baseband signal to an
R&S
AMU200A that superimposes fading on the signal and routes it back. Thus fading
can be added to the forward link signal.
Configuring and activating fading
1. Connect the DUT and the R&S AMU200A to the R&S
CMW (see chapter 2.2.1.3,
"Test Setup for External Fading Scenarios" , on page 16).
2. Configure the signaling application according to the test to be performed, espe-
cially select an external fading scenario and configure the forward link settings.
3. In the configuration tree, section "IQ Settings > IQ Out", note the "Baseband PEP"
and the "Crest Factor".
4. Configure the R&S AMU200A, especially the following settings:
Reference oscillator settings:
● Source = External
● External Reference Frequency = 10 MHz
Baseband input settings for all used connectors:
● Sample Rate = User Defined, 100 MHz
● Baseband Input Level: enter the crest factor and the PEP displayed in
step 3 .
Digital I/Q output settings for all used connectors:
● Sample Rate = User Defined, 100 MHz
● Set Level Via = PEP
● PEP = PEP value displayed in
step 3
5. In the R&S AMU200A, activate fading and note the signal level. If you add noise to
the signal, note the signal level without noise.
6. Configure the I/Q input of the R&S
CMW:
In the configuration tree, section "IQ Settings > IQ In > Baseband Level", enter the
signal level noted in the previous step.
Alternatively it is also possible, to specify the signal output level of the R&S
AMU200A, to note the resulting PEP and to enter this PEP value at the R&S
CMW
for "Baseband PEP". But this is not recommended.
7. Turn on the forward link signal at the signaling application and set up a connection.
The configuration is now complete. Fading is active.
Note that a reconfiguration of the settings at the R&S AMU200A during an active
connection to the DUT may result in the loss of the connection or in erroneous
measurement results.
After a reconfiguration of the baseband input settings of the R&S AMU200A, you
must turn the forward link signal at the signaling application off and on again.
General Description
深圳德标仪器
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