Rohde & Schwarz CMU-K20, Руководство по эксплуатации

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Non Signalling Mode CMU-K20/-K21/-K22/-K23/-K24
1115.6088.12 2.6 E-10
Non Signalling Mode
In the Non Signalling mode, a GSM-specific RF signal can be generated and a RF signal with GSM
characteristics can be analyzed. Compared to the Signalling mode test times may be reduced consid-
erably. Moreover, the measurements are not restricted to the specified channel and MS output power
ranges of the network. The most common application is module test and test of mobiles in a special
test
mode .
In our example we use the GSM signal generated by the CMU itself to demonstrate the main features
of the
Non Signalling mode. This is analogous to the RF measurement example in the CMU operating
manual.
Step 1
The Analyzer/Generator menu contains
softkeys and hotkeys to configure the RF
generator signal of the CMU and to define
the RF analyzer settings.
#
Moreover, the current measurement re-
sults for power, frequency and phase er-
rors of the received signal are displayed.
$
At present, all parameters are set to default
values. They can be directly changed by
means of the softkeys and hotkeys. User-
defined parameters will be saved to the
non-volatile RAM for later sessions when
the CMU is switched off.
⇓
!
Proceed as outlined in section RF Non
Signalling Measurements , chapter 2 of
CMU200 operating manual to connect
RF1 to RF2 via a coax cable. Open the
Connection Control menu and perform
the appropriate RF input and output set-
tings.
!
Adapt the Analyzer Settings – Fre-
quency setting to the expected input
signal frequency (default generator fre-
quency).
!
Press Generator – RF Level and the
ON/OFF key to switch on the generator.
The analyzer adapts itself to the RF input
level (autoranging).
%
⇓
The measurement results are indicated in
the
P/t Norm. GMSK and Ext. Phase Error
GMSK output fields.
!
Select (press) the Power/t Norm. GMSK
softkey.
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