Update to InstrumentTo open the instrument node, click in the tree view. If there is more than one instrument connection, there will be a corresponding number of Instrument listings in the tree view. Tool Bar Functions are the same for all connected instruments. Other parameters, however, may vary. Choose your connected Instrument below to go the appropriate table of parameters.
M9383B VXG-m and M9384B VXG Microwave Signal Generators
M9420A/M9421A VXT PXIe Vector Transceiver
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Update to InstrumentClick the button to send the parameters to the connected instrument.
Update from InstrumentClick the button to retrieve the parameters from the connected instrument.
PresetClick the button to set the signal generator to a factory-defined or user-defined state.
Refer to the signal generator's user's guide for information on setting a user-defined state.
DC CalClick the button to execute an I/Q DC calibration to minimize errors associated with offset voltages.
minimizes I/Q offset errors for a single frequency only and must be repeated if the signal generator's settings change.
Download a waveform to set the correct parameters for the target instrument and activate this button.
Power SearchSet ALC to to activate this button.
Click the button to execute a manual power search calibration. This is an internal calibration routine that improves output power accuracy when the ALC is turned off. A power search is recommended for pulse-modulated signals with pulse-widths less than two microseconds.
Download a waveform to set the correct parameters for the target instrument.
HintSelect the checkbox then click a parameter cell to display a brief description of the parameter.
Displays the model number of the currently connected instrument.
(M9383B/M9384B only)
Choice: On | Off
Default: On
Double-click or use the drop-down menu to enable or disable automatic DC I/Q calibration.
On − the signal generator automatically performs a DC I/Q calibration after downloading a waveform.
Off − the signal generator does not perform a DC I/Q calibration after downloading a waveform.
(M9383B/M9384B only)
Choice: depends on the connected instrument
Default: 1
Sets the channel number for M9383B VXG-m and M9384B VXG microwave signal generators.
Range: for frequency range values, see the signal generator's data sheet
Enter a value to set the signal generator’s output frequency. Use abbreviations for faster entry (example: 1g = 1.000000000000 GHz).
Range: for amplitude range values, see the signal generator's data sheet
Enter a value to set the signal generator’s output amplitude in dBm.
Choice: Off | On
Default: On
Double-click or use the drop-down menu to turn the signal generator’s RF output or .
Choice: RF Out | RFIO FD | RFIO HD
Default: RF Out
Double-click or use the drop-down menu to select the signal generator's RF output port.
(M9383B/M9384B 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:
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 to to enable this parameter.
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 to to enable this parameter.
Range:
N5182A: -1 dB to 1 dB in 0.001 dB steps
All other models: -1 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 to to enable this parameter.
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 to to enable this parameter.
Choice: RF | BB
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 grayed out.
Choice:
N5172B/N5182B: RF Output | External I/Q Output | Dig Bus Output
Other Models: RF Output | External I/Q Output
Default: 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 as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.
optimizes the I/Q OUT path by applying calibration factors to only this path, leaving the RF OUT and Digital Bus paths uncalibrated. With as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.
optimizes the Digital Bus path by applying calibration factors to only this path, leaving the RF OUT and I/Q OUT paths uncalibrated. With as the I/Q Source selection, the instrument automatically optimizes all paths, so no optimization path selection is needed.
This parameter is not available for all instrument model numbers and may be grayed out.
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.
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.
Choice: Free Run | Internal | Manual(Trigger Key) | Bus | External 2
Default: Free Run
Double-click or use the drop-down menu to select the input trigger source.
Choice: Continuous | Single
Default: Continuous
Double-click or use the drop-down menu to select the waveform repetition type after it is triggered.
Choice: Marker 1 | Marker 2 | Marker 3 | Marker 4
Default: Marker 1
Double-click or use the drop-down menu to select the output trigger type, the output trigger is routed to Trigger 2 port on the front panel.
(M9383B/M9384B 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 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.
(M9383B/M9384B only)
Choice: On | Off
Default: On
Enables or disables ALC On and ALC Bandwidth couplings.
For IQ modulation, ALC Auto and Power Search Auto should be On.
Choice: Off | On
Default: Off
Double-click or use the drop-down menu to enable or disable the automatic level control.
– The ALC circuit constantly monitors and controls the output power level.
– No automatic leveling occurs.
Choice: Auto | 100.00 Hz | 1.00 kHz | 10.00 kHz | 100.00 kHz
Default: Auto
Double-click or use the drop-down menu to select an ALC bandwidth.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: Fixed | Modulation | RMS
Default: RMS
Double-click or use the drop-down menu to select one of the following reference signals when doing a power search.
– Power search uses a fixed 0.5 V reference.
– Power search uses the AC bias from the actual modulating signal.
– Power search uses a DC bias value equivalent to the value derived from the file header or the calculated value from the current I/Q data.
Set to to enable this parameter.
Choice: Normal | Minimum
Default: Normal
Double-click or use the drop-down menu to select the level of the output power control during a power search routine.
– Performs power searches without setting the internal step attenuator to its maximum setting. Glitches and power changes may be present during the search.
– Sets the signal generator's step attenuator to its maximum setting during power search to protect sensitive circuits.
Set to to enable this parameter.
(M9383B/M9384B only)
Choice: On | Off
Default: On
Toggles Power Search Mode between On or Off.
When enabled, power search calibration routine is executed whenever an instrument setting is modified. This includes changes to frequency, amplitude and modulation.
For IQ modulation, ALC Auto and Power Search Auto should be On.
For M9383B/M9384B, this parameter is grayed out and set to Very Slow when ALC Auto is On.
Displays the sample clock. The sample clock frequency of the signal generator is automatically calculated by the program. The range depends on the connected instrument.
Choice: Internal | External
Default: Internal
Double-click or use the drop-down menu to select the signal generator’s VCO Clock.
- the signal generator uses its internal VCO Clock.
- the signal generator uses an external VCO Clock
This parameter is not available for all instrument model numbers and may be grayed out.
Range: 1 to 100% (100% = no scaling)
Default: 70%
Enter a scaling value for the signal generator to apply to the waveform while it is playing. Use scaling to get the best dynamic range without overflowing the I and Q digital-to-analog converters (DAC) and to reduce the overshoot associated with the DAC interpolation filter. Waveform Runtime Scaling does not change the data in the waveform file.
Choice: Auto | 2.1 MHz | 40 MHz | Through
Default: Auto
Double-click or use the drop-down menu to select an I/Q modulation filter value.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: Auto | 40 MHz | Through
Default: Auto
Double-click or use the drop-down menu to select an I/Q output filter value.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: Auto | Manual
Default: Auto
Set the modulation attenuation mode for the I/Q modulator to automatic or manual.
– the signal generator optimizes the modulation attenuation for the current conditions.
– applies the value set in the cell.
Range: 0 to 40 dB (minimum increment 0.01 )
Default: 6.00 dB
Use this parameter to reduce the signal level driving the I/Q modulation block. Adjusting the attenuation may reduce signal distortion and improve the overall dynamic range.
Set the Modulation Attenuation Mode to to enable this parameter.
Choice: Off | On
Default: Off
Double-click or use the drop-down menu to enable or disable the signal generator's high crest mode.
– processes high-crest-factor arbitrary I/Q waveforms with less distortion. For crest factors higher than 4 dB, you should reduce I/Q Modulation Attenuation levels by 1 dB for each dB above that level. High crest mode reduces the maximum output level and degrades power level accuracy.
– disables the high crest mode.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: Internal | External
Default: Internal
Double-click or use the drop-down menu to select the signal generator’s ARB reference source.
– the signal generator uses its internally generated 10 MHz signal as the reference source.
– the signal generator uses an external signal as the reference frequency for the baseband I/Q signal. See the signal generator’s user’s guide for information on external references.
This parameter is not available for all instrument model numbers and may be grayed out.
Range: 0.250 to 100 MHz
Default: 10.00 MHz
Enter a frequency value when using an externally supplied reference signal. See the signal generator user’s guide for information on external references.
Set ARB Reference to to enable this parameter.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: None | Marker 1 | Marker 2 | Marker 3 | Marker 4
Default: Marker 3
Double-click or use the drop-down menu to select an RF blanking function. Pulse/RF Blanking turns off the RF output signal during specific conditions determined by the marker.
– disables RF blanking.
through – selects a marker to activate RF blanking.
RF blanking incorporates ALC hold, so you do not need to select ALC hold when using RF blanking.
Do not blank longer than 100 ms to avoid exceeding the ALC hold limit.
Choice: None | Marker 1 | Marker 2 | Marker 3 | Marker 4
Default: None
Double-click or use the drop-down menu to select a marker for ALC hold. Use ALC hold when you have a waveform signal that has idle periods, or when the increased dynamic range with RF blanking is not desired.
– disables ALC hold.
through – assigns a marker for the ALC hold function.
When the specified marker polarity is positive and the marker signal is low (no marker points), ALC hold is on, and the output power level does not respond to changes to the signal amplitude. When the marker signal is high, the ALC samples the waveform points and averages the waveform amplitudes to set the ALC circuitry for the next ALC hold period.
RF blanking incorporates ALC hold, so there is no need to select ALC hold when using RF blanking.
Limit ALC Hold to no more than 100 ms, as the ALC Level may degrade.
The hold selection remains until you reconfigure it, preset the signal generator, or cycle the signal generator power.
Incorrect ALC settings can cause a sudden unleveled condition to occur. An unleveled RF output can damage a DUT or connected instrument. Ensure that you set markers such that the ALC obtains a sample that accounts for the high power levels within the signal.
Choice: None | Marker 1 | Marker 2 | Marker 3 | Marker 4
Default: None
Double-click or use the drop-down menu to select a marker for enabling the alternate amplitude function.
None – disables the alternate amplitude function.
through – assigns a marker for the alternate amplitude function.
When the specified marker polarity is positive and the marker signal is low (no marker points), alternate amplitude is off. When the marker signal is high, the alternate amplitude function is on.
Configure the alternate amplitude parameters from the Amplitude hardkey menu of the signal generator.
For more information about alternate amplitude and marker settings, refer to the signal generator's user's guide.
This parameter is not available for all instrument model numbers and may be grayed out.
Choice: Positive | Negative
Default: Positive
Double-click or use the drop-down menu to select the active polarity for Marker 1.
– the marker signal is high during the marker points.
– the marker signal is high during the period of no marker points.
Choice: Positive | Negative
Default: Positive
Double-click or use the drop-down menu to select the active polarity for Marker 2.
– the marker signal is high during the marker points.
– the marker signal is high during the period of no marker points.
Choice: Positive | Negative
Default: Positive
Double-click or use the drop-down menu to select the active polarity for Marker 3.
– the marker signal is high during the marker points.
– the marker signal is high during the period of no marker points.
Choice: Positive | Negative
Default: Positive
Double-click or use the drop-down menu to select the active polarity for Marker 4.
– the marker signal is high during the marker points.
– the marker signal is high during the period of no marker points.
Choice: Continuous | Single | Gated | Segment Advance
Default: Continuous
Double-click or use the drop-down menu to select the triggering mode.
– selects the continuous triggering mode, which enables the signal generator to repeat the modulating signal indefinitely until you turn off the modulation format, change triggers, or select another waveform.
– sets up a waveform to play once after receiving a trigger.
– sets the signal generator to the gated trigger mode, which causes the waveform (modulating signal) to repeatedly start and stop in response to an externally applied trigger signal. To use the gated trigger mode, you must select as the Trigger Source.
– controls the way the signal generator plays segments within a sequence. This includes determining whether a segment plays once or continuously, and when the sequence advances to the next segment. See Segment Advance.
(M9383B/M9384B only)
Choice: Continuous | Single
Default: Continuous
Double-click or use the drop-down menu to select the triggering mode.
Continuous – selects the continuous triggering mode, which enables the signal generator to repeat the modulating signal indefinitely until you turn off the modulation format, change triggers, or select another waveform.
Single – sets up a waveform to play once after receiving a trigger.
Choice: Trigger Key | External | Bus
Default: External
Double-click or use the drop-down menu to select the triggering method.
– selects the front panel hardkey as the trigger source. After making this selection, press the Trigger hardkey to trigger a waveform.
– causes a waveform to trigger from an externally supplied trigger signal.
– enables a command sent through the GPIB, LAN, or AUXILIARY IO (RS-232) input connector to trigger a waveform.
(M9383B/M9384B only)
Choice: Trigger Key | External | Bus | Immediate
Default: External
Adjusts the trigger source applied to the PATT TRIG IN or AUX I/O connectors.
Trigger Key − selects the front panel hardkey as the trigger source. After making this selection, press the Trigger hardkey to trigger a waveform.
External − enables you to trigger a waveform with an externally supplied trigger signal.
Immediate − enables immediate triggering of the waveform playing.
Bus − enables you to trigger a waveform by sending a command through the GPIB, LAN, or AUXILIARY IO (RS-232) input connector.
(M9383B/M9384B only)
Choice: 50 Ohm | High Impedance
Default: High Impedance
Select the way the trigger line is terminated in the hardware.
(M9383B/M9384B only)
Range: -3.5 to 3.5
Default: 0.5
Specifies the threshold level in volts at which the trigger transitions states.
Choice: Positive | Negative
Default: Negative
Sets the polarity of the external trigger. This parameter is active only if you select external (Ext) as the trigger source.
Positive – the signal generator triggers an event when it detects a rising edge on the PAT TRIG IN signal.
Negative – the signal generator triggers an event when it detects a falling edge on the PAT TRIG IN signal.
Choice: Pattern Trigger In 1 | Pattern Trigger In 2
Default: Pattern Trigger In 1
Double-click or use the drop-down menu to select the rear-panel input for the external trigger signal. must be selected as the trigger source.
– selects the PATTERN TRIG IN rear-panel BNC connector
– selects the AUXILIARY I/O rear panel connector
Choice: Positive | Negative
Default: Negative
Sets the polarity of the external trigger. This parameter is active only if you select as the trigger source.
– the signal generator triggers an event when it receives a negative change in the signal at the PAT TRIG IN or AUX I/O rear panel connector.
– the signal generator triggers an event when it receives a positive change in the signal at the PAT TRIG IN or AUX I/O rear panel connector.
Choice: On | Off
Default: Off
Turns the external trigger delay off or on. This parameter is active only after selecting as the trigger source.
Range:
N5182A: 8 ns to 30 s, in 8 ns steps
All other models: 10 ns to 40 s, in 10 ns steps
Default:
M9383B/M9384B: 0 s
All other models: 1 ms
Sets the amount of time to delay the signal generator's response to an external trigger, in 8 ns or 10 ns steps. The delay is a path (time) delay between the time the signal generator receives the trigger and when it responds to the trigger.
Choice: Free Run | Trigger & Run | Reset & Run
Default: Free Run
Double-click or use the drop-down menu to select the continuous mode and one of the following trigger responses.
– immediately triggers when you turn the format on.
– waits for and starts on the first trigger; ignores subsequent triggers.
– waits for and starts on the first trigger; resets and plays on a subsequent trigger.
Choice: Buffered Trigger | No Retrigger | Restart on Trigger
Default: Buffered Trigger
Double-click or use the drop-down menu to select the single mode and one of the following trigger responses.
– the waveform segment ignores triggers during playback
– causes a waveform to accept a trigger during playback and to restart after the current play finishes.
– causes a waveform to accept a trigger during playback and to restart immediately after receiving a trigger.
Choice: Single | Continuous
Default: Continuous
Double-click or use the drop-down menu to select the segment advance mode and one of the following trigger responses.
– causes a segment to play once and to wait for a trigger before the sequence advances to the next segment.
– causes a segment to play continuously until receiving another trigger. Upon receiving the trigger, the sequence advances to the next segment, which then plays continuously.
Choice: Active High | Active Low
Default: Active High
Double-click or use the drop-down menu to select the gated mode and one of the following trigger responses. To use the gated trigger mode, you must also select .
– causes waveform playback to start when the trigger signal goes low and to stop when the trigger signal goes high.
– causes waveform playback to start when the trigger signal goes high and to stop when the trigger signal goes low.
(M9383B/M9384B only)
Range: 4 ns to 10 s
Default: 1 ms
Sets the amount of time in seconds to hold off until the next trigger.
(M9383B/M9384B only)
Choice: On | Off
Default: On
Turns the Playback Synchronization off or on.
Only applied when Trigger Source is set to External and Trigger Type is set to Continuous.
Choice: On | Off
Default: Off
Double-click or use the drop-down menu to enable or disable adding real-time, non-repeating additive white Gaussian noise (AWGN) to the carrier being modulated by the waveform being played.
– enables the addition Real-time Noise.
– disables the addition of Real-time Noise.
Range: -100 to 100 dB
Default: 0 dB
Enter the noise power to be applied to a waveform. The carrier power is defined as the total modulated signal power before noise power is added. When you add noise, the power output from the signal generator does not change; it is the sum of carrier power and the added noise power. A positive value makes C larger than N.
Range:
N5182A 1.0 Hz to 100 MHz
E4438C 1.0 Hz to 80 MHz
Default: 1.0 Hz
Specifies the bandwidth over which the noise power is integrated for calculating the carrier to noise ratio (the bandwidth of the target carrier). Also, the maximum upper range is limited to Base Sampling Rate x OSR before download is finished.
Range: 1 to 2
Default: 1
Displays the flat noise bandwidth factor for the applied real-time noise.
When the Sample Clock is < 50 MHz, the Noise Bandwidth Factor adjusts the RF flat noise bandwidth to be either at least 0.8 times the sample rate for a bandwidth factor of 1, or 1.6 times the sample rate if the bandwidth factor is 2.
When the Sample Clock is > 50 MHz, noise cannot be enabled if the Noise Bandwidth Factor is 2. Any oversampling in a waveform will effectively make the noise bandwidth that many times wider than the signal bandwidth.
The Noise Bandwidth is calculated as follows:
The noise bandwidth is at least 0.8 * [ARB Sample Clock] * [Noise Bandwidth Factor]
This parameter is not available for all instrument model numbers and may be grayed out.
Range: 0.001 Hz to 100.000 MHz
Default: 1.000 Hz
Set or change the noise bandwidth.
This parameter is not available for all instrument model numbers and may be grayed out.