Rohde & Schwarz SMBV100B - Page 442

Multi-Instrument Setups
R&S
®
SMBV100B
440User Manual 1178.4460.02 ─ 03
1) enable an appropriate measurement time
2) perform one measurement for each baseband source
3) set the measurement period to a time value that is long enough to capture
several periods of the input signal.
– Determined automatically
The R&S SMBV100B can receive the values from the connected transmitter.
If the external digital signal source is a second Rohde & Schwarz instrument, it
signals the peak level and the RMS level of the signal over the digital input
interface. To enable the R&S SMBV100B to receive these values, enable the
parameter "DIG IQ Auto Setting" on page 461.
In the second automatic way, the R&S SMBV100B adjusts the corresponding input
fields with the measured/received values. The internal gain control mechanism
uses these received values to adjust the input signal gain to achieve an optimal
dynamic range.
●
Sample Rate
External input signals with sample rates different than the system clock are resam-
pled, as illustrated on Figure 8-4.
Figure 8-4: Resampling principle of external digital baseband signals
* = Max. sample rate depends on connected device
f
input
= Max. sample rate
The R&S SMBV100B can process digital signals with sample rate f
input
= 400 Hz to
200 MHz, where the maximum value (f
sample, max
) depends on the capabilities of the
connected transmitting/receiving device.
●
Maximum modulation bandwidth
A baseband signal with a sample rate f
smaple
< f
smaple, max
(i.e. smaller than the used
system clock) is interpolated, see Figure 8-4. The resulting modulation bandwidth
is calculated as Sample Rate * 0.8.
With a sample rate f
smaple, max
of exactly 600 MSamples/s, the modulation band-
width is 160 MHz.
Control and Operation of External Instruments