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Keysight EXG and MXG X-Series Signal Generators User’s Guide
Basic Digital Operation (Option 653/655/656/657)
I/Q Calibration
The I/Q adjustment, I/Q Delay, is not for adding impairments; its function is to compensate for any
latency between the EVENT output signals (marker signals) and the RF output.
I/Q Calibration
Use the I/Q calibration for I and Q signal corrections. What aspects of the I and Q signal is corrected
depends on whether the signal is internally or externally generated.
When you perform an I/Q calibration, that calibration data takes precedence over the factory–
supplied calibration data. The calibration routines improve performance that may degrade over
time or due to temperature changes. An I/Q calibration should be run when the ambient
temperature has varied by at least ±5 degrees Celsius from the ambient temperature at which the
previous calibration was run.
— The user I/Q calibration is persistent (i.e. Pressing instrument preset or cycling power does not
remove the user I/Q calibration from memory).
— If the start and stop frequencies are set to the same value, then the calibration will be performed
exactly at that frequency and the data will be persisted in the bounding calibration array
elements.
Table 9-2
I/Q Adjustments Uses
I/Q Adjustment
Effect
Impairment
Offset
Carrier feedthrough
dc offset
Quadrature Angle
EVM error
phase skew
I/Q images
I/Q path delay
I/Q Skew
EVM error
high sample rate phase
skew or I/Q path delay
I/Q Gain Balance
I/Q amplitude difference
I/Q gain ratio
I/Q Phase
I/Q phase rotation
RF phase adjustment
Correction
Internal I and Q
External I and Q
Offset
X
X
Gain Balance
X
X
Quadrature
Error
X
X
