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Qpsk, To select qpsk modulation, To select carrier waveform shape – RIGOL DG4000 Series User Manual

Page 123: To set carrier phase, Qpsk -23

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Chapter 5 Modulated Waveform Output

RIGOL

DG4000 Series User’s Guide

5-23

QPSK


When QPSK (Quadrature Phase Shift Keying) is selected, you can configure the
generator to “shift” its output phase among four preset phases (“carrier phase”
and three “modulating phases”). The “shift” frequency (QPSK rate) is determined
by the internal signal level of the instrument.

To Select QPSK Modulation


Press ModTypeQPSK to enable QPSK function.
 When Mod is enabled, Sweep or Burst will be automatically disabled (if

enabled currently).

 After QPSK is enabled, the instrument will generate QPSK waveform with the

currently specified carrier and modulating waveforms.


To Select Carrier Waveform Shape


QPSK carrier waveform could be Sine, Square, Ramp or arbitrary waveform
(except DC), and the default is Sine.
 Press the front panel key Sine, Square, Ramp or ArbSelect Wform

(or User, the pre-defined waveform can not be DC) to select desired carrier
waveform shape.

 Pulse (basic waveform), Noise and DC could not be used as carrier waveform.

To Set Carrier Phase


After carrier waveform shape is selected, press Start Phase to highlight it and use
the numeric keyboard or direction keys and knob to input the desired phase. The
phase range is from 0º to 360º and the default is 0º.