Applying Digital Predistortion - R&S SGT100A User Manual

®
R&S SGT100A
Save/Recall Polynomial
Accesses the "Save/Recall" dialog, i.e. the standard instrument function for storing and
recalling the complete dialog-related settings in a file. The provided navigation possibil-
ities in the dialog are self-explanatory.
The file name and the directory it is stored in are user-definable; the file extension is
however predefined.
The polynomial files are files with extension *.iq_poly, see
nomial function file"
Remote command:
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:COEFficients:
CATalog?
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:COEFficients:
STORe
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:COEFficients:
LOAD
Polynomial Order
Defines the polynomial order n, that is the number of polynomial coefficients (see
"About the Polynomial Function"
Select "Apply" to confirm the settings.
Remote command:
See
COEFficients
Polynomial constant and coefficients
Sets the polynomial constant a
The polynomial constant and coefficients influence the envelope shape.
Remote command:
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:COEFficients
on page 444
Apply, OK
Triggers the instrument to adopt the selected function.
Use "OK" to apply the setting and exits the dialog.
Remote command:
See
COEFficients

7.6 Applying Digital Predistortion

Digital predistortion (DPD) is one of the methods, used to improve the efficiency of RF
power amplifiers. In the R&S SGT, the generated digital signal can be deliberately
AM/AM and AM/PM predistorted.
User Manual 1176.8674.02 ─ 07
on page 150.
on page 445
on page 445
on page 445
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:
on page 444
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:SHAPing:
on page 444
on page 150).
and the polynomial coefficients a
0
Signal Generator Settings
Applying Digital Predistortion
"File format of the poly-
to a .
1 n
178