R&S SGT100A, User Manual

Page: 219 / 593

Signal Generator Settings
R&S
®
SGT100A
188 User Manual 1176.8674.02 ─ 07
Figure 7-22: Predistortion Settings > From Table: Understanding the displayed information
1a = Normalized value of the current RF RMS power level
2a = Normalized value of the current PEP of the generated RF signal
1b, 2b = Correction values
white dashed line = Ideal zero correction function; no correction is necessary
yellow curve
= Predistortion function
3a, 3b = Input Range (PEP
in
)
4 = Positive correction coefficients to compensate values below the ideal ones
5 = Values greater than the PEPin Max are ignored
The dialog covers the settings for digital predistortion, like select and enabling an
AM/AM and/or AM/PM predistortion, select the way the predistortion function is
defined and specify the correction values.
Shaping ....................................................................................................................... 188
Interpolation ................................................................................................................ 189
Invert correction values ............................................................................................... 189
Input Range (PEP
in
) .................................................................................................... 190
Pre-Gain ......................................................................................................................190
Shaping Table ............................................................................................................. 191
Polynomial Coefficients ...............................................................................................191
Normalized Data ......................................................................................................... 191
Shaping
Selects the method to define the correction coefficients.
"From Table" As value pairs in form of a shaping table.
Select "AM/AM or AM/PM Shaping Table" to access the settings, see
Chapter 7.6.3.3, "Edit Predistortion Table Settings" , on page 191
Applying Digital Predistortion