GUI Reference
R&S
®
CMW-KM750/-KM751
36
User Manual 1173.9670.02 ─ 05
If a correction table for frequency-dependent attenuation is active for the chosen con-
nector, then the table's name and a button are displayed. Press the button to display the
table entries.
Remote command:
Band / Frequency - Channel
Center frequency of the RF analyzer. Set this frequency to the frequency of the measured
RF signal to obtain a meaningful measurement result.
You can specify the RF frequency in two ways:
●
Enter the frequency directly. The band and channel settings can be ignored or used
for validation of the entered frequency. For validation select the designated band.
The channel number resulting from the selected band and frequency is displayed.
For an invalid combination no channel number is displayed.
●
Select a band and enter a channel number valid for this band. The R&S
CMW cal-
culates the resulting frequency.
Remote command:
Expected Nominal Power
Defines the nominal power of the RF signal to be measured. An appropriate value for TD-
SCDMA signals is the peak output power at the DUT during the measurement interval.
The "Ref. Level" is calculated as follows:
Reference Level = Expected Nominal Power + User Margin
Note:
The actual input power at the connectors (i.e. the "Reference Level" minus the
"External Attenuation (Input)" value, if all power settings are configured correctly) must
be within the level range of the selected RF input connector; refer to the data sheet.
Remote command:
User Margin
Margin that the R&S
CMW adds to the "Expected Nominal Power" in order to determine
its reference power ("Ref. Level"). The "User Margin" is typically used to account for the
known variations of the RF input signal power, e.g. the variations due to a specific channel
configuration.
The appropriate values depend on the configuration of the UL TD-SCDMA signal, e.g.
on the active channels and gain factors. For a 12.2 kbps Reference Measurement Chan-
nel (RMC), a value of 5 dB is appropriate.
Remote command:
Mixer Level Offset
Varies the input level of the mixer in the analyzer path. A negative offset reduces the
mixer input level, a positive offset increases it. Optimize the mixer input level according
to the properties of the measured signal.
Parameters and Settings
