Waveform and List Format
R&S
®
SGT100A
507
User Manual 1176.8674.02 ─ 07
PeakOffset_dB
Defines the peak level offset of the signal relative to full scale for
the ARB signal in the
WAVEFORM
tag. The offset is defined in
ASCII float format.
The value usually equals 0 dB as usually the I/Q samples
(signed 16-bit integer values) are modulated to full scale: Full
scale = 0 dB = max. amplitude of vector of I/Q samples = |S
IQ
|
max = sqrt(I
2
+Q
2
)max = (2
15
)-1 = 32767.
A positive
PeakOffset_dB
value indicates that a headroom to
full scale is provided when generating the waveform. A negative
PeakOffset_dB value indicates that overrange is likely for some
samples, i.e. clipping might occur.
The crest factor can be calculated from the two values as fol-
lows:
Crest Factor = |PeakOffset_dB - RMSOffset_dB|
Example:
{LEVEL OFFS: 3.45,2}
BB:ARB:WAV:TAG? 'LEVEL OFFS'
Queries the content of the
LEVEL OFFS
tag of the selected
waveform file.
Response: 3.45,2
The level of the waveform is below full scale, clipping does not
occur.
Usage:
Setting only
{SAMPLES: Samples}
(recommended for waveforms)
The tag contains the number of I/Q samples in the waveform in ASCII format.
On multi segment waveforms, this tag contains the total I/Q samples of all segments.
Example:
{SAMPLES: 4333}
BB:ARB:WAV:TAG? 'SAMPLES'
Queries the content of the
SAMPLES
tag of the selected wave-
form file.
Response: '4333'
The waveform contains 4333 I/Q samples.
Usage:
Setting only
{[TRACE] LIST [#]: Pos0:Val0;Pos1:Val1;...Posx:Valx;...PosN-1:ValN-1}
optional for waveforms)
The tag contains the data for the marker and control signals in the control list or the
marker signals of ARB waveforms. To select which of these signals is defined,
[TRACE]
and the associated number are used. For ARB waveforms, it is only mean-
ingful to define marker signals (on ARB multi segment waveforms these tags will be
ignored).
Tag Description
