When an M9383B/M9384B/M9484C is connected, you will see the display as below:
(M9383B/M9384B/M9484C only)
Choice: On | Off
Default: On
Double-click or use the drop-down menu to turn the internal channel correction Off or On.
Choice: Off | On
Default: Off
Double-click or use the drop-down menu to turn the I/Q adjustments or .
– The values entered for I Offset, Q Offset, and so on are applied to the I and Q signals.
– I/Q adjustment values are not applied to the I and Q signals.
Range: -20% to 20%
Step: 0.025%
Default: 0.000%
Enter a DC offset value to apply to the I signal before the I/Q modulator. Use this offset to remove imperfections in the in-phase signal or to introduce calibrated impairments.
When using this setting to minimize the LO feed-through signal, optimum performance is achieved when the adjustment is made after any other I/Q path adjustments. If other adjustments are made after minimization is performed, the LO feed-through signal may increase.
Set to to enable this parameter.
Range: -20% to 20%
Step: 0.025%
Default: 0.000%
Enter a DC offset value to apply to the Q signal before the I/Q modulator. Use this offset to remove imperfections in the quadrature-phase signal or to introduce calibrated impairments. When using this setting to minimize the LO feed-through signal, optimum performance is achieved when the adjustment is made after any other I/Q path adjustments. If other adjustments are made after minimization is performed, the LO feed-through signal may increase.
Set to to enable this parameter.
Range: -1 dB to 1 dB in 0.001 dB steps
Default: 0.000 dB
Enter a value to set the gain for the I signal relative to the Q signal.
Example: If you enter a value of 1 dB, the I signal will have 1 dB more amplitude than the Q signal. Use the gain balance to remove imperfections in I and Q or introduce calibrated impairments.
Set to to enable this parameter.
(M9383B/M9384B/M9484C only)
Range: -1 dB to 1 dB
Default: 0 dB
Set to to enable this parameter.
Enter a gain ratio, by which I gain exceeds Q gain.
For example, if you enter a value of 1 dB, the I signal will have 1 dB more amplitude than the Q signal. Use the gain balance to remove imperfections in I and Q or introduce calibrated impairments.
Range: -10 to 10 degrees
Default: 0.00 degrees
Enter a value to adjust the Q phase angle. When the quadrature skew is zero, the phase angle between the I and Q vectors is 90 degrees. Positive skew increases the angle from 90 degrees; negative skew decreases the angle from 90 degrees.
Set to to enable this parameter.
Choice: RF | BB (Baseband)
Default: RF
Double-click or use the drop-down menu to select the I/Q timing skew path.
Set to to enable this parameter.
This parameter is not available for all instrument model numbers and may be greyed out.
Choice: RF Output | External I/Q Output
Default: RF Output
Double-click or use the drop-down menu to select the I/Q correction optimized path.
optimizes the RF OUT path by applying calibration factors to only this path, leaving the I/Q OUT and Digital Bus paths uncalibrated.
optimizes the I/Q OUT path by applying calibration factors to only this path, leaving the RF OUT and Digital Bus paths uncalibrated.
This parameter is not available for all instrument model numbers and may be greyed out.
Range: -500 ns to 500 ns
Default: 0.0 seconds
Enter a value to set the time delay between I and Q.
A positive value delays the I signal relative to the Q signal.
A negative value delays the Q signal relative to the I signal.
Range: -250 ns to 250 ns
Default: 0.0 seconds
Enter a value to change the absolute phase of both I and Q with respect to triggers and markers. A positive value delays I and Q. This value affects both the external I/Q out signals and the baseband signal modulated on the RF output. This adjustment cannot be used with constant envelope modulation and does not affect external I/Q inputs.
The limits are determined by the rate of the current format.
This parameter is not available for all instrument models and may be grayed out or not shown in GUI.
(M9383B/M9384B/M9484C only)
Choice: On | Off
Default: Off
Double-click or use the drop-down menu to enable or disable the inverse phase rotation of the IQ signal by swapping the I and Q inputs.
(M9383B/M9384B/M9484C only)
Choice: On | Off
Default: On
Filters the system RF flatness correction coefficients over the instantaneous bandwidth indicated in the waveform header (or in the “Occupied Bandwidth” settings area under the Signal block when Waveform File is the Vector Modulation Signal Mode). This has the potential to improve EVM performance by not having to correct for flatness errors outside the requested bandwidth.