Specifications

Programming Guide 2-21
ESG Family Signal Generators Programming Commands and Examples
:DM and :BURSt Subsystems (ESG-D and ESG-DP Series)
I/Q Gain Ratio Adjustment
:DM:IQADjustment:GAIN <val><unit>
:DM:IQADjustment:GAIN?
This command is used to set the I/Q gain ratio in dB, by which I gain exceeds Q gain.
Choices for the variables <val> and <unit> range from
−4.0 to +4.0 dB.
*RST Value: 0.00 dB
I/Q Modulation Phase Polarity
:DM:POLarity[:ALL] NORMal|INVerted
:DM:POLarity[:ALL]?
This command sets the polarity of the I/Q modulation signal. The choices are Normal or
Inverted. In the inverted mode the input applied to the I INPUT connector is physically
routed to the Q input port of the internal I/Q modulator. In addition, the input applied to
the Q INPUT connector is physically routed to the I input port of the internal I/Q
modulator. This inverts the direction of phase rotation of the I/Q modulation. If you have
enabled a digital modulation mode (Option UN8 only), I/Q phase polarity will be
automatically set to normal. You can override this setting with this command.
*RST Value: Normal
Q Channel Offset Adjustment
:DM:IQADjustment:QOFFset <val><unit>
:DM:IQADjustment:QOFFset?
This command is used to set the Q channel offset, in percent of full scale. 100% offset is
equivalent to 500 mV at the input connector. Choices for the variables <val> and <unit>
range from
−100.0 to +100.0%.
*RST Value: 0.00%
Quadrature Skew Adjustment
:DM:IQADjustment:QSKew <val><unit>
:DM:IQADjustment:QSKew?
This command is used to adjust the phase angle between the I and Q vectors. When the
quadrature skew is zero, the phase angle is 90 degrees. Positive skew increases the angle
from 90 degrees while negative skew decreases the angle from 90 degrees. The range of
values allowed is 10 degrees with a minimum increment of 0.1 degrees. However, if you’re
operating the signal generator in the 3.3 to 4 GHz frequency range, quadrature skew
settings greater than ±5 degrees will not be within specifications.
*RST Value: 0.0 degrees