Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
362 Operating Manual 1407.6062.32 ─ 08
Number of Carriers
Sets the number of carriers for the multi carrier waveform.
By default the multi carrier table lists 1 carrier. A maximum of 32 carriers can be config-
ured and activated.
When the number of carriers is increased, the multi carrier table is extended by adding
further lines at the end of the table. If these carrier already have been defined before, the
settings are preset according to the former settings. Otherwise the parameters are preset
with the default values.
SCPI command:
​
[:
​
SOURce<hw>]:
​
BB:
​
ARB:
​
MCARrier:
​
CARRier:
​
COUNt
​
on page 522
Carrier Spacing
Sets the frequency spacing between adjacent carriers of the multi carrier waveform.
The carriers are arranged symmetrically around the RF carrier.
The maximum carrier spacing is limited to
Carrier spacing = Total baseband bandwidth /(Number of carriers - 1) ;
The total baseband bandwidth is 120 MHz for R&S SMBV equipped with option B10/B50
or 60 MHz for R&S SMBV-B51.
Note: In order to avoid wrap-around problems, the effective "Carrier Spacing" might be
slightly modified.
The Carrier Spacing is rounded in that way that the carrier closest to the center RF fre-
quency shows no phase jump assuming that the carrier is unmodulated.
●
For odd number of carriers:
RoundedCarrierSpacing=1/OutputSignalDuration* round(CarrierSpacing * Output-
SignalDuration);
●
For even number of carriers:
RoundedCarrierSpacing=2/OutputSignalDuration*round(0.5 *CarrierSpacing *Out-
putSignalDuration).
SCPI command:
​
[:
​
SOURce<hw>]:
​
BB:
​
ARB:
​
MCARrier:
​
CARRier:
​
SPACing
​
on page 523
Crest Factor Mode
Selects the mode for optimizing the crest factor by calculating the carrier phases.
The crest factor represents the ratio of the peak voltage value to the rms voltage value.
The higher the crest factor and resulting dynamics of a signal, the greater the requirement
for a power amplifier fed by the signal to be linear.
The following modes are available:
"Off" There is no automatic setting for minimizing or maximizing the crest
factor. The "Phase" setting as defined in the carrier table is in use.
"Minimize" The crest factor is minimized by internally calculating optimized carrier
phases. The Phase setting displayed in the carrier table is invalid.
"Maximize" The crest factor is maximized by internally calculating optimized carrier
phases. The Phase setting displayed in the carrier table is invalid.
SCPI command:
​
[:
​
SOURce<hw>]:
​
BB:
​
ARB:
​
MCARrier:
​
CFACtor:
​
MODE
​
on page 525
Baseband Signal - Baseband Block