5.Panel Operation
36
How to set the parameters of PSK
(1)
Press the
Mod
function key, then press the
Type
softkey, turn the
knob
to select
PSK
, press the
OK
softkey.
(2)
Select carrier wave shape
:
The carrier wave can be
Sine
,
Square
,
Ramp
, or
Arbitrary
wave (except DC).
Press
,
,
, or
to select a desired carrier wave shap.
(3)
Set carrier wave parameters
:
Press
the wave shap key
of the selected carrier wave to display the waveform
and parameters of the carrier wave. You can change the parameters of the
carrier wave. Press
Mod
to return to the modulation mode interface.
(4)
Select modulating wave source
:
Press the
Source
softkey to select
Internal
or
External
as the modulating wave
source.
(5)
If you select
Internal
, the modulating wave is set as a Square with 50% duty
cycle.
Press
the
PSK Rate
softkey to set the PSK rate. The rate at which the
output phase shifts between the carrier phase and the modulating phase is
determined by PSK rate (for internal source only). The range is 2 mHz – 1 MHz.
If you select
External
, use the
Mod/FSK/Trig
connector at the rear panel to
input the external modulating signal. Press the
Slope
softkey to switch between
Positive
and
Negative
polarity of the modulating wave to control the output
phase. Set the slope to
Positive
, the generator would output the carrier phase
when the external input signal is logic low level, and output the modulating
phase when the external input signal is logic high level. The situation is the
opposite when the slope is set to
Negative
.
(6)
Set PSK phase deviation
:
Press the
Deviation
softkey to set the modulating phase deviation.
3FSK (3 Frequency Shift Keying)
3 Frequency Shift Keying modulation is a modulation technique that shifts the
output signal frequency among three preset frequencies: the carrier frequency and
two hop frequencies. The shift frequency (3FSK rate) is determined by the internal
signal level of the instrument. The 3FSK user interface is shown below.
