R&S SGT100A, Руководство пользователя

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Signal Generator Settings
R&S
®
SGT100A
164 User Manual 1176.8674.02 ─ 07
V
cc
Offset ← DC Modulator characteristics
Applies a voltage offset on the supply voltage V
cc
Min/Max , i.e. compensates a possible
offset from the external DC modulator. The envelope output voltage V
out
Min/Max is
reduced by this value to maintain the supply voltage V
cc
in the defined value range.
Figure 7-13: Effect of a Vcc offset
Remote command:
[:SOURce<hw>]:IQ:OUTPut[:ANALog]:ENVelope:VCC:OFFSet
on page 439
PA characteristics
Refer to the product documentation of the PA for information on its characteristics.
The following settings are required:
V
cc
Min/Max ← PA characteristics
Sets or displays the minimum and maximum values of the supply voltage V
cc
, as
required by the used power amplifier (PA).
The value range of the supply voltage V
cc
is determined by the allowed peak-to-peak
driving voltage V
pp
of the used external DC modulator and the enabled V
cc
Offset.
V
cc
Max
≤
V
pp
Max
The V
cc
is calculated as follows:
V
cc
= Vout * Gain + V
cc
Offset
Example:
Envelope Voltage Reference = V
cc
V
cc
Offset = 0 mV
V
cc
Max = 1 V = 0 dBV
Gain = 3 dB
V
cc
Max [dBV] - Gain [dB] = V
out
Max or
V
out
Max = 0 dBV - 3 dB = -3 dBV = 0.708 V
Generation of Envelope Tracking Signals