Rohde & Schwarz SMBV100B, User Manual

Page: 226 / 1030

Configuring the Internal Baseband Source
R&S
®
SMBV100B
224 User Manual 1178.4460.02 ─ 03
●
Multi-carrier waveforms composed of several signals from the same communica-
tion standard as in LTE Advanced.
3.8.1 Required Options
See Chapter 3.6.1, "Required Options" , on page 145.
Multi-carrier waveform files require the corresponding Digital Standard options
(R&S
SMBV100B-K2xx) of all included standards.
3.8.2 About the Multi-Carrier Waveforms
This chapter provides background information on the ARB functionality for generating
of multicarrier signals and the impact of the provided settings. Refer to
Chapter 3.8.4,
"How to Use the Multi-Carrier Function" , on page 238 for information on how to use
the provided settings to configure a multicarrier signal.
The multi-carrier waveforms are convenient way to configure the broadband test sig-
nals required for transmitter or receiver tests. Even complex multi-carrier scenarios
composed of signals from different digital standards can be created and used for these
tests.
Because the multi-carrier files are processed by the ARB generator, the composed
waveform file must be created before it is loaded to and played by the ARB. The
R&S
SMBV100B stores the created multi-carrier waveform file under user definable
name; as with the single carrier waveforms, the used file extension is
*.wv
. The instru-
ment appends additional information to the header of the composed waveform file.
When the created waveform is loaded, the graphical interface displays information on
clock rate, number of samples and creation day.
General principle for composing the multicarrier signal
The following is a list of the general steps used for composing the multicarrier signal:
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In the default mode, the up to 512 carriers are equally spaced and centered toward
the RF frequency or the baseband DC line.
The carrier spacing is adjustable within the total available bandwidth. The total RF
bandwidth of the composed multicarrier signal may not exceed the available RF
bandwidth (see data sheet).
●
Another possibility is to define the center frequency of each of the carrier individu-
ally, see also
Chapter 3.8.2.1, "Defining the Carrier Frequency" , on page 225.
●
Each carrier can be separately defined in terms of power, phase and modulated
input signal.
To define the leveling of the composed multicarrier signal, use the parameter
Power Reference
●
Optionally, crest factor optimization can be applied (see Chapter 3.8.2.2, "Optimiz-
ing the Crest Factor" , on page 225).
Generating Multi-Carrier Signals