Real Time

3. I/Q

I/Q Adjustments

Choice: Off | On

Default: Off

Double-click or use the drop-down menu to turn the I/Q adjustments On or Off.

On – The values entered for I Offset, Q Offset, and so on are applied to the I and Q signals.

Off – I/Q adjustment values are not applied to the I and Q signals.

I Offset

Range:

N5182A: –20% to 20%

All other models: –50% to 50%

Default:

0.0%

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. For more information, refer to the User Guide or Key Reference for the signal generator you are using.

Set I/Q Adjustments to On to enable this parameter.

Q Offset

Range:

N5182A: –20% to 20%

All other models: –50% to 50%

Default:

0.0%

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. For more information, refer to the User Guide or Key Reference for the signal generator you are using.

Set I/Q Adjustments to On to enable this parameter.

I/Q Gain Balance

Range:

N5182A: –1 dB to 1 dB in 0.001 dB steps

All other models: –4 dB to 4 dB in 0.01 dB steps

Default:

0.00 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.

Set I/Q Adjustments to On to enable this parameter.

Quadrature Angle Adjustment

Range: –10 to 10 degrees

Default: 0 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 I/Q Adjustments to On to enable this parameter.

I/Q Timing Skew Path

Choice: RF | BB

Default: RF

Double-click or use the drop-down menu to select the I/Q timing skew path.

Set I/Q Adjustments to On to enable this parameter.

I/Q Correction Optimization Path

Choice:

N5172B/N5182B: RF Output | External I/Q Output | Dig Bus Output

Other Models: RF Output | External I/Q Output

Default: RF Output

RF Output optimizes the RF OUT path by applying calibration factors to only this path, leaving the I/Q OUT and Digital Bus paths uncalibrated. With External as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.

Ext I/Q Output optimizes the I/Q OUT path by applying calibration factors to only this path, leaving the RF OUT and Digital Bus paths uncalibrated. With External as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.

Dig Bus Output optimizes the Digital Bus path by applying calibration factors to only this path, leaving the RF OUT and I/Q OUT paths uncalibrated. With External as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.

I/Q Skew

Range:

N5182A: –800 ns to 800 ns, in 1 ps steps

All other models: –2.0 to 2.0 seconds, in 1 ps steps

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.

I/Q Delay

Range: –1.0 to 1.0 seconds, 1 ps step

Default: 0.0 ps

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.

Related Topics

Instrument