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Keysight EXG and MXG X-Series Signal Generators User’s Guide
Basic Digital Operation (Option 653/655/656/657)
Setting the Baseband Frequency Offset
The baseband frequency offset value is one of the file header parameters (
), which means
you can store this value with the waveform. When you select a waveform with a stored frequency
offset value, the signal generator changes the current value to match the stored file header value. If
there is no stored baseband offset frequency value for the current waveform, the signal generator
uses the last set frequency offset value.
You can also use the Save function (
) to store this value as part of the signal generator
setup. When you Recall a setup stored with the Save function, the baseband frequency offset value
becomes the current instrument setting value, disregarding the stored file header value.
Use the following steps to offset the carrier from LO/carrier feedthrough. This example uses the
factory supplied waveform,
SINE_TEST_WFM
available in the Dual ARB Player. To view the output
for this example, connect the RF OUTPUT of the signal generator to the input of a spectrum
analyzer.
1.
Select and play the waveform.
a.
Press
Mode
>
Dual ARB
>
Select Waveform
.
b.
In the
Segment On BBG Media
column, select
SINE_TEST_WFM
.
c.
Press
Select Waveform
.
2.
Generate the waveform: Press
ARB Off On
to On.
3.
Configure the carrier signal:
a.
Set the carrier signal to 1 GHz.
b.
Set the amplitude to 0 dBm.
c.
Turn on the RF OUTPUT.
4.
Press
Mode
>
Dual Arb
>
ARB Setup
>
More
>
Baseband Frequency Offset
>
20 MHz
.
The modulated RF signal is now offset from the carrier frequency by 20 MHz as shown in the
following figures.
Changing the baseband frequency offset may cause a DAC over range
condition that generates error
628, Baseband Generator DAC over
range
. The signal generator incorporates an automatic scaling feature to
minimize this occurrence. For more information, see
