Adjustments Block

The Adjustments block applies to N5186A only.

This topic describes the parameters of the ClosedAdjustments block.

Channel Optimization

Optimize Dynamic Range with OBW

System RF Flatness Correction

I/Q Common Delay

Swap I & Q

IQ Adjustments ClosedSetup

IQ Adjustments On

I Offset

Q Offset

Gain Balance

I/Q Time Skew

Quadrature Angle

AWGN ClosedSetup

AWGN State

Carrier to Noise Ratio Format

Carrier to Noise Ratio C/N

Carrier to Noise Ratio Eb/No

Carrier Bit Rate (bps)

Carrier Bandwidth

Flat Noise Bandwidth

Power Control Mode

Total Power

Carrier Power

Channel Noise Power

Flat Noise Power

Total Noise Power

Output Mux Mode

CW Interferer ClosedSetup

CW Interferer On

Frequency Offset

Signal Power

Power Control Mode

Power Relative

Power Absolute

Total Power

Channel Optimization

Applies to N5186A only

This command is accepted, but no action is performed. This preference can be used to allow programmatic compatibility with other Keysight Technologies signal generators.

SCPI Command

[:SOURce]:DM:INTernal:CHANnel:OPTimization EVM|ACP

[:SOURce]:DM:INTernal:CHANnel:OPTimization?

SCPI Example

DM:OPT:CHAN ACP

DM:OPT:CHAN?

Preset

EVM

Range

EVM | ACP

State Saved

Yes

Backward Compatibility SCPI

N51xxB:

[:SOURce]:DM:INTernal:CHANnel:OPTimization

Backward Compatibility SCPI Notes

For N51xxB:

Command is accepted with no action performed, sending the SCPI command does not generate an error. Query will always return EVM.

Optimize Dynamic Range with OBW

Applies to N5186A only.

Enables the optimization based on occupied bandwidth (OBW).

This feature filters the system RF flatness correction coefficients over the instantaneous bandwidth, indicated in the waveform header, or in the Waveform File Occupied Bandwidth GUI field. This has the potential to improve EVM performance by not having to correct for flatness errors outside the requested bandwidth. For example, if the maximum optioned bandwidth is 2 GHz, but your signal is 800 MHz wide and centered, then flatness corrections will ignore any adjustments that would be needed to flatten the 600 MHz bands on either side of your signal. This can reduce the dynamic range consumed by the flatness correction, improving signal to noise ratio and EVM at frequencies where the unused bands have significant roll off.

See also, Waveform Header and Waveform File Occupied Bandwidth.

GUI Location

Adjustments > Optimize Dynamic Range with OBW

SCPI Command

[:SOURce]:IQOut<channel>:CORRection:OPTimization:DYNamic:RANGe:OBW ON|OFF|1|0

[:SOURce]:IQOut<channel>:CORRection:OPTimization:DYNamic:RANGe:OBW?

SCPI Example

IQO:CORR:OPT:DYN:RANG:OBW ON

IQO:CORR:OPT:DYN:RANG:OBW?

Preset

ON

State Saved

Yes

System RF Flatness Correction

Applies to N5186A only.

Disabling this function disables the factory calibrated RF channel flatness equalizer. Depending on the hardware channel response, this may hurt or improve the EVM. This is due to the dynamic range implications as it relates to signal to noise ratio. The greater the RF hardware variations in flatness, the greater the amount of correction is required, the greater the correction effectively reduces the number of resolution DAC bits that can be used, which degrades the signal to noise ratio and therefore potentially EVM. The trade-off is to balance between flatness and signal to noise ratio.

GUI Location

Adjustments > System RF Flatness Correction

SCPI Command

[:SOURce]:IQOut<channel>:CORRection:CHANnel:FLATness[:STATe] ON|OFF|1|0

[:SOURce]:IQOut<channel>:CORRection:CHANnel:FLATness[:STATe]?

SCPI Example

IQO:CORR:CHAN:FLAT ON

IQO:CORR:CHAN:FLAT?

Preset

ON

State Saved

Yes

I/Q Common Delay

Applies to N5186A only.

Enables you to change the time delay of all signals on a channel, both I and Q together, signals with respect to triggers, markers and the reference clock.

On instruments with I/Q outputs this value affects both the external I/Q out signals and the baseband signal modulated on the RF output. If the instrument has Option EXT, this adjustment does not affect external I/Q inputs.

This setting is effective regardless of the state of the I/Q Adjustments Enabled.

GUI Location

Adjustments > I/Q Common Delay

SCPI Command

[:SOURce]:IQOut<channel>:DELay <time>

[:SOURce]:IQOut<channel>:DELay?

SCPI Example

IQO:DEL 100 ns

IQO:DEL?

Preset

0

State Saved

Yes

Min

0 s

Max

For N5186A: 41.6666666666667 ns

Resolution

For N5186A: 250 fs

Swap I & Q

Applies to N5186A only.

Enables or disables the inverse phase rotation of the IQ signal by swapping the I and Q inputs.

This setting is effective regardless of the state of the I/Q Adjustments Enabled.

GUI Location

Adjustments > Swap I & Q

SCPI Command

[:SOURce]:IQOut<channel>:IQSWap ON|OFF|1|0

[:SOURce]:IQOut<channel>:IQSWap?

SCPI Example

IQO:IQSW 1

IQO:IQSW?

Preset

OFF (check box cleared)

State Saved

Yes

IQ Adjustments

Applies to N5186A only.

Accesses the I/Q Adjustments Setup screen, where you can configure these parameters. Once you complete your configuration, click or tap Back and this area updates to reflect your custom configuration.

IQ Adjustments On

Applies to N5186A only.

This check box enables or disables the I/Q adjustment settings.

GUI Location

Adjustments > I/Q Adjustments > IQ Adjustments On

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment[:STATe] ON|OFF|1|0

[:SOURce]:IQOut<channel>:IQADjustment[:STATe]?

SCPI Example

IQO:IQAD 1

IQO:IQAD?

Preset

OFF (check box cleared)

State Saved

Yes

I Offset

Applies to N5186A only.

Adjusts the I channel offset value in percent relative to the RMS of the modulated channel RMS.

Adjusting this value reduces dynamic range by the adjustment.

GUI Location

Adjustments > I Offset

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment:IOFFset <real>

[:SOURce]:IQOut<channel>:IQADjustment:IOFFset?

SCPI Example

IQO:IQAD:IOFF 12

IQO:IQAD:IOFF?

Preset

0

Dependencies

Effective only when the state of the I/Q Adjustments Enabled is set to ON.

State Saved

Yes

Range

-20 to 20

Resolution

0.001

Q Offset

Applies to N5186A only.

Adjusts the Q channel offset value in percent relative to the RMS of the modulated channel RMS.

Adjusting this value reduces dynamic range by the adjustment.

GUI Location

Adjustments > Q Offset

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment:QOFFset <real>

[:SOURce]:IQOut<channel>:IQADjustment:QOFFset?

SCPI Example

IQO:IQAD:QOFF 12

IQO:IQAD:QOFF?

Dependencies

Effective only when the state of the I/Q Adjustments Enabled is set to ON.

Preset

0

State Saved

Yes

Range

-20 to 20

Resolution

0.001

Gain Balance

Applies to N5186A only.

Adjusts the ratio of I to Q while preserving the composite, vector magnitude. Adding gain (+x dB) to the signal increases the I component and decreases the Q component proportionally. Reducing gain (-x dB) decreases the I component and increases the Q component proportionally.

GUI Location

Adjustments > Gain Balance

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment:GAIN <ampl>

[:SOURce]:IQOut<channel>:IQADjustment:GAIN?

SCPI Example

IQO:IQAD:GAIN 0.5

IQO:IQAD:GAIN?

Preset

0

Dependencies

Effective only when the state of the I/Q Adjustments Enabled is set to ON.

State Saved

Yes

Range

-10 to 10 dB

Resolution

0.001

I/Q Time Skew

Applies to N5186A only.

Changes the I/Q skew which is a time delay difference between the I and Q signals. Equal and opposite skew is applied to both I and Q and affects the RF output and I/Q output paths simultaneously. A positive value delays the I signal relative to the Q signal, and a negative value delays the Q signal relative to the I signal.

GUI Location

Adjustments > I/Q Time Skew

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment:SKEW <time>

[:SOURce]:IQOut<channel>:IQADjustment:SKEW?

SCPI Example

IQO:IQAD:SKEW 10 ns

IQO:IQAD:SKEW?

Preset

0

Dependencies

Effective only when the state of the I/Q Adjustments Enabled is set to ON.

State Saved

Yes

Min

For N5186A: -83.3333 ns

Max

For N5186A: 83.3333 ns -19.5 to 19.5 ns

Resolution

For N5186A: 0.00025 ns

Quadrature Angle

Applies to N5186A only.

Adjusts the phase angle (quadrature skew) between the I and Q vectors by increasing or decreasing the Q phase angle.

Positive skew increases the angle from 90 degrees while negative skew decreases the angle from 90 degrees. When the quadrature skew is zero, the phase angle between the I and Q vectors is 90 degrees.

GUI Location

Adjustments > Quadrature Angle

SCPI Command

[:SOURce]:IQOut<channel>:IQADjustment:QSKew

[:SOURce]:IQOut<channel>:IQADjustment:QSKew?

SCPI Example

IQO:IQAD:QSK 0.5

IQO:IQAD:QSK?

Preset

0

Dependencies

Effective only when I/Q Adjustments Enabled is set to ON.

State Saved

Yes

Range

-20 to 20 deg

Resolution

0.001

AWGN

Applies to N5186A only.

AWGN is the ability to apply Additive White Gaussian Noise in real-time to the carrier modulated by the waveform being played.

The following symbols are used to describe Min/Max values for the settings used to configure the AWGN:

PT: Total Power in mW ()

PT,min: Min limit of Total Power in mW ( )

PT,max: Max limit of Total Power in mW ( )

PC: Carrier Power in mW (

PN: Total Noise Power in mW ()

PNc: Channel Noise Power in mW ( )

RCN: Ratio of Carrier Power and Channel Noise Power in linear value

RN: Ratio of Total Noise Power and Channel Noise Power

Rb: Ratio of Effective Bandwidth and Sampling Bandwidth.

PF: Flat Noise Power in mW ( )

Relationship among each symbol is as follows.

Noise Power Ratio means the ratio of Channel Noise Power to Total Noise Power.

The equation above means that the Total Noise Power becomes larger than Channel Noise Power by dB if Flat Noise Bandwidth and Carrier Bandwidth are the same.

AWGN State

Applies to N5186A only.

Adds real-time AWGN to the carrier modulated by the waveform being played.

GUI Location

Adjustments > AWGN > AWGN On

SCPI Command

[:SOURce]:IQOut<channel>:AWGN[:STATe] ON|OFF|1|0

[:SOURce]:IQOut<channel>:AWGN[:STATe]?

SCPI Example

IQO:AWGN ON

IQO:AWGN?

Preset

OFF

Dependencies

Option 403 is required to turn on this parameter.

State Saved

Yes

Carrier to Noise Ratio Format

Applies to N5186A only.

GUI Location

Adjustments > AWGN > Carrier to Noise Ratio Format

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:CNFormat CN|EBNO

[:SOURce]:IQOut<channel>:AWGN:CNFormat?

SCPI Example

IQO:AWGN:CNF EBNO

IQO:AWGN:CNF?

Preset

CN

Choices

C/N | Eb/No

State Saved

Yes

Carrier to Noise Ratio C/N

Applies to N5186A only.

Sets the carrier to noise ratio (C/N) in dB. The carrier power is defined as the total modulated signal power without noise power added. The noise power is applied over the specified bandwidth of the carrier signal.

GUI Location

Adjustments > AWGN > Carrier to Noise Ration > C/N

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:CN <rel_ampl>

[:SOURce]:IQOut<channel>:AWGN:CN?

SCPI Example

IQO:AWGN:CN 10 dB

IQO:AWGN:CN?

Preset

0 dB

State Saved

Yes

Min

Carrier to Noise Ratio may be clipped by the min value of Power

  • When Power Control Mode is Total: -100 dB.

  • When Power Control Mode is Carrier:

  • When Power Control Mode is Total Noise:

  • When Power Control Mode is Channel Noise:

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Max

 

  • When Power Control Mode is Total: 100 dB

  • When Power Control Mode is Carrier:

  • When Power Control Mode is Total Noise:

  • When Power Control Mode is Channel Noise:

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Resolution

0.01 dB

Step Increment

0.01 dB

Carrier to Noise Ratio Eb/No

Applies to N5186A only.

If signal power is in watts and bit rate is in bits per second, Eb is in units of joules (watt-seconds). N0 is the noise spectral density, the noise power in a 1 Hz bandwidth, measured in watts per hertz or joules.

This function is only available when Carrier to Noise Ratio Format is set to Eb/No.

GUI Location

Adjustments > AWGN > Carrier to Noise Ratio Format set to Eb/No > Eb/No

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:EBNO <rel_ampl>

[:SOURce]:IQOut<channel>:AWGN:EBNO?

SCPI Example

IQO:AWGN:EBNO 10 dB

IQO:AWGN:EBNO?

Preset

0 dB

State Saved

Yes

Min

(Minimum value of C/N) - 10log10(bitRate/carrierBandWidth)

Max

(Maximum value of C/N) - 10log10(bitRate/carrierBandWidth)

Resolution

0.01 dB

Step Increment

0.01 dB

Carrier Bit Rate (bps)

Applies to N5186A only.

Sets a value of the carrier bit rate (gross bit rate) for purposes of calculating the Eb/N0 (energy per bit over noise power density at the receiver). When the carrier to noise ratio format is set to Eb/N0, the adjustment of the carrier bit rate will have an immediate impact on the carrier to noise ratio as specified by Eb/N0. The carrier bit rate is derived from the symbol rate and bits per symbol of the modulation.

This function is only available when Carrier to Noise Ratio Format is set to Eb/No.

GUI Location

Adjustments > AWGN > Carrier to Noise Ratio Format set to Eb/No > Carrier Bit Rate (bps)

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:CBRate

[:SOURce]:IQOut<channel>:AWGN:CBRate?

SCPI Example

IQO:AWGN:CBR 5

IQO:AWGN:CBR?

Preset

1 bps

State Saved

Yes

Min

1 bps

Max

999 Gbps

Resolution

0.001 bps

Step Increment

0.001 bps

Carrier Bandwidth

Applies to N5186A only.

Sets the carrier bandwidth over which the AWGN is applied. The carrier RMS power and the noise power will be integrated over the selected carrier-bandwidth for the purposes of calculating carrier to noise ratio (C/N).

GUI Location

Adjustments > AWGN > Carrier Bandwidth

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:CBWidth <freq>

[:SOURce]:IQOut<channel>:AWGN:CBWidth?

SCPI Example

IQO:AWGN:CBW 10 Hz

IQO:AWGN:CBW?

Preset

1 Hz

State Saved

Yes

Min

1 Hz

Max For Bandwidth, see Vector Modulation Bandwidth Limitations table.

Resolution

0.001 Hz

Step Increment

5 kHz

Flat Noise Bandwidth

Applies to N5186A only.

Selects the flat noise bandwidth value of the real–time noise for an ARB waveform. Typically, this value is set slightly wider than the signal bandwidth.

GUI Location

Adjustments > AWGN > Flat Noise Bandwidth

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:BANDwidth|BWIDth <freq>

[:SOURce]:IQOut<channel>:AWGN:BANDwidth|BWIDth?

SCPI Example

IQO:AWGN:BAND 10 Hz

IQO:AWGN:BAND?

Preset

State Saved

Yes

Min

Max For Bandwidth, see Vector Modulation Bandwidth Limitations table.

Resolution

Step Increment

5 kHz

Power Control Mode

Applies to N5186A only.

The Power Control Mode can be set to either Total, Carrier, Total Noise, or Channel Noise. Each mode is defined as follows:

Total

Adjusts the total power and C/N (Carrier to Noise Ratio). The carrier power, channel noise power, and total noise power are set by the total power, C/N, and the rest of the noise settings, and change as any noise parameter is adjusted to keep the total power and the C/N at their last specified values.

Carrier

Adjusts the carrier power and C/N. The total power, channel noise power, and total noise power are set by the carrier power, C/N, and the rest of the noise setting and change as any noise parameter is adjusted to keep the carrier power and the C/N at their last specified values. It can be set manually using the Carrier Power option.

Total Noise

Adjusts the total noise power and C/N. The total power, channel noise power, and carrier power are set by the total noise power, C/N, and the rest of the noise settings and change as any noise parameter is adjusted to keep the total noise power and the C/N at their last specified values. It can be set manually using the Total Noise Power option.

Channel Noise

Adjusts the channel noise power and C/N. The total power, total noise power, and carrier power are set by the channel noise power, C/N, and the rest of the noise settings and change as any noise parameter is adjusted to keep the channel noise power and the C/N at their last specified values. It can be set manually using the Noise Power in Channel option.

Flat Noise

Adjusts the flat noise power and C/N. The total power, channel noise power, and carrier power are set by the flat noise power, C/N, and the rest of the noise settings and change as any noise parameter are adjusted to keep the total noise power and the C/N at their last specified values. It can be set manually using the Flat Noise Power option.

GUI Location

Adjustments > AWGN > Power Control Mode

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:POWer:CONTrol[:MODE] TOTal|CARRier|NOISe|NCHannel|NFLat

[:SOURce]:IQOut<channel>:AWGN:POWer:CONTrol[:MODE]?

SCPI Example

IQO:AWGN:POW:CONT NOIS

IQO:AWGN:POW:CONT?

Preset

TOTal

Choices

Total | Carrier | Total Noise | Channel Noise l Flat Noise

State Saved

Yes

Total Power

Applies to N5186A only.

GUI function only, no SCPI equivalent commend.

Shows the sum of Total Noise Power and Carrier Power.

GUI Location

Adjustments > AWGN > Total Power

Carrier Power

Applies to N5186A only.

Sets the current carrier power level.

In Carrier control mode, the total power will be adjusted to achieve the specified carrier power, and the carrier power level will be maintained regardless of changes to the other noise parameters. A change to the total power will change the carrier power setting appropriately to maintain the C/N ratio.

In the other control modes, this will adjust the total power once for the specified carrier power level, after which the carrier power could change if any noise parameters are adjusted.

GUI Location

Adjustments > AWGN > Carrier Power

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:POWer:CARRier <ampl>

[:SOURce]:IQOut<channel>:AWGN:POWer:CARRier?

SCPI Example

IQO:AWGN:POW:CARR 20 dBm

IQO:AWGN:POW:CARR?

Preset

N5186A: 103.52 dBm

State Saved

Yes

Min

The min value of the carrier power is calculated using the min limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Max

The max value of the carrier power is calculated using the max limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Resolution

0.01 dBm

Step Increment

5 dBm

Channel Noise Power

Applies to N5186A only.

Sets the current channel noise power level.

In the Channel Noise control mode, the total power will be adjusted to achieve the specified channel noise power and the channel noise power level will be maintained regardless of changes to the other noise parameters. A change to the total power will change the channel noise power setting appropriately to maintain the C/N ratio.

In the other control modes, this will adjust the total power once for the specified channel noise power level, after which the channel noise power could change if any noise parameters are adjusted.

GUI Location

Adjustments > AWGN > Channel Noise Power

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:CHANnel <ampl>

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:CHANnel?

SCPI Example

IQO:AWGN:POW:NOIS:CHAN -30 dBm

IQO:AWGN:POW:NOIS:CHAN?

Preset

-123.52 dBm

State Saved

Yes

Min

The min value of the channel noise power is calculated using the min limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Max

The max value of the channel noise power is calculated using the max limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Resolution

0.01 dBm

Step Increment

5 dBm

Flat Noise Power

Applies to N5186A only.

Sets the current noise power level for the region of the Flat Noise Bandwidth.

In the Channel Noise control mode, the total power will be adjusted to achieve the specified channel noise power and the flat noise power level will be maintained regardless of changes to the other noise parameters. A change to the total power will change the flat noise power setting appropriately to maintain the C/N ratio.

In the other control modes, this will adjust the total power once for the specified flat noise power level, after which the flat noise power could change if any noise parameters are adjusted.

GUI Location

Adjustments > AWGN > Flat Noise Power

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:FLAT <ampl>

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:FLAT?

SCPI Example

IQO:AWGN:POW:NOIS:FLAT -100 dBm

IQO:AWGN:POW:NOIS:FLAT?

Preset

State Saved

Yes

Min

You can model the minimum of flat noise power as a function of the channel noise power minimum, which itself is calculated using the min limit of total power and C/N.

This calculated value is applicable only when both AWGN Status and Enable Vector Modulation Signal are on.

Max

You can model the maximum of flat noise power as a function of the channel noise power maximum, which itself is calculated using the min limit of total power and C/N.

This calculated value is applicable only when both AWGN Status and Enable Vector Modulation Signal are on.

Resolution

0.00000001 dBm

Step Increment

5 dBm

Total Noise Power

Applies to N5186A only.

Sets the current total noise power level.

In the Noise control mode, the total power will be adjusted to achieve the specified total noise power and the total noise power level will be maintained regardless of changes to the other noise parameters. A change to the total power will change the total noise power setting appropriately to maintain the C/N ratio.

In the other control modes, this will adjust the total power once for the specified total noise power level, after which the total noise power could change if any noise parameters are adjusted.

GUI Location

Adjustments > AWGN > Total Noise Power

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:TOTal <ampl>

[:SOURce]:IQOut<channel>:AWGN:POWer:NOISe:TOTal?

SCPI Example

IQO:AWGN:POW:NOIS:TOT 15 dBm

IQO:AWGN:POW:NOIS:TOT?

Preset

-122.55 dBm

State Saved

Yes

Min

The min value of the total noise power noise power is calculated using the min limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Max

The max value of the total noise power noise power is calculated using the max limit of the total power and C/N.

This calculated value is applicable only when both AWGN Status and vector modulation are on.

Resolution

0.01 dBm

Step Increment

5 dBm

Output Mux Mode

Applies to N5186A only.

Enables diagnostic control of additive noise, such that only the noise, only the carrier, or the sum of both the noise and the carrier are output from the internal baseband generator. With ALC off, this feature enables direct measurement of just the carrier or the noise contributions to the total power. The system will still behave as if both the noise and the carrier are present on the output when it comes to determining the Auto Modulation Attenuation and the RMS level for RMS Power Search.

GUI Location

Adjustments > AWGN > Output Mux Mode

SCPI Command

[:SOURce]:IQOut<channel>:AWGN:MUX SUM|CARRier|NOISe

[:SOURce]:IQOut<channel>:AWGN:MUX?

SCPI Example

IQO:AWGN:MUX SUM

IQO:AWGN:MUX?

Preset

SUM

Choices

Carrier+Noise | Carrier | Noise

State Saved

Yes

CW Interferer

Applies to N5186A only.

Adds a CW tone placed relative to the carrier modulated by the waveform being played.

In some cases, better RF performance of a CW interferer is required, or you may need a dynamic range that is greater than the dynamic range available. For these cases, additional RF outputs can be used to generate the CW interferer, combining the waveforms in RF external to the instrument, to minimize the intermodulation products and improve EVM performance.

CW Interferer On

Applies to N5186A only.

Enables or disables adding a CW tone (an interferer) to the carrier modulated by the waveform being played.

Enables or disables adding a CW tone (an interferer) to the carrier modulated by the waveform being played. The CW tone cannot be on at the same time as AWGN in the Adjustment block or Frequency Offset in the Signal block; setting CW Interferer on will turn off AWGN and set baseband frequency offset to 0 Hz.

GUI Location

Adjustments > CW Interferer > CW Interferer On

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer[:STATe] ON|OFF|1|0

[:SOURce]:IQOut<channel>:CWINterferer[:STATe]?

SCPI Example

IQO:CWIN ON

IQO:CWIN?

Preset

OFF

Dependencies

Option 403 is required to turn on this setting.

Couplings

For N5186A:

If baseband Frequency Offset is a non-zero value and the CW Interferer is set to ON, the baseband Frequency Offset is set to 0 Hz and a settings conflict error message is generated.

If AWGN in the Adjustment block is on and the CW Interferer is set to ON, AWGN is set to off and a settings conflict error message is generated.

State Saved

Yes

Frequency Offset

Applies to N5186A only.

Sets the offset of the CW interferer from the CW carrier, which is the center of the modulated waveform.

GUI Location

Adjustments > CW Interferer > Frequency Offset

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer:FREQuency:OFFSet <frequency>

[:SOURce]:IQOut<channel>:CWINterferer:FREQuency:OFFSet?

SCPI Example

IQO:CWIN:FREQ:OFFS -10 MHZ

IQO:CWIN:FREQ:OFFS?

Preset

0 Hz

State Saved

Yes

Min

- (BW/2)

For BW, see Vector Modulation Bandwidth Limitations table.

Max

BW/2

For BW, see Vector Modulation Bandwidth Limitations table.

Resolution

For N5186A: 0.00000762939 Hz

Step Increment

5 kHz

Signal Power

Applies to N5186A only.

Sets the power level at the input of the CW interferer: the signal block power + AWGN. 

When CW Interferer is on, a coupling exists between the Signal power and the RF Output Power Total (in the RF Output block); as the Signal power is changed the RF Output Power Total is adjusted to reflect Signal power + CW Interferer power. If the RF Output Power Total is changed, the Signal power is adjusted to reflect RF Output Power Total – CW Interferer power. If the range of Signal power is exhausted, and the CW Interferer mode is Absolute, the Absolute power is then adjusted.

GUI Location

Adjustments > CW Interferer > Signal Power

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer:POWer:SIGNal <ampl>

[:SOURce]:IQOut<channel>:CWINterferer:POWer:SIGNal?

SCPI Example

IQO:CWIN:POW:SIGN 20 dBm

IQO:CWIN:POW:SIGN?

Preset

-103.52 dBm

State Saved

Yes

Min

The min value of the signal power is calculated using the min limit of the total power and CW Interferer Power.

This calculated value is applicable only when both CW Interferer State and vector modulation are on.

Max

The max value of the signal power is calculated using the max limit of the RF Output Power Total and CW Interferer Power. See Max value of RF Output Power Total

This calculated value is applicable only when both CW Interferer State and vector modulation are on.

Resolution

0.01 dBm

Step Increment

5 dBm

Power Control Mode

Applies to N5186A only.

The CW interferer power can be specified as either relative to the signal power, or an absolute power level.

GUI Location

Adjustments > CW Interferer > CW Interferer Power > Control Mode

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer:POWer:MODE RELative|ABSolute

[:SOURce]:IQOut<channel>:CWINterferer:POWer:MODE?

SCPI Example

IQO:CWIN:POW:MODE REL

IQO:CWIN:POW:MODE?

Preset

ABS

Range

RELative | ABSolute

State Saved

Yes

Power Relative

Applies to N5186A only.

Controls the relative power of the CW Interferer with respect to the modulated waveform, when the CW Interferer mode is Relative. Note that as CW Interferer power increases, all other signals will lose fidelity. For measurements that need both high dynamic range and high-fidelity low power signals, an instrument with a second RF Channel is recommended.

GUI Location

Adjustments > CW Interferer > CW Interferer Power > Control Mode (Relative) > Relative to Signal Power

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer:POWer:RELative <ampl>

[:SOURce]:IQOut<channel>:CWINterferer:POWer:RELative?

SCPI Example

IQO:CWIN:POW:REL -1

IQO:CWIN:POW:REL?

Preset

0 dB

State Saved

Yes

Min

-96 dB

Max

96 dB

Resolution

0.01 dB

Step Increment

5 dB

Power Absolute

Applies to N5186A only.

Controls the absolute power of the CW Interferer, when the CW Interferer mode is Absolute. Note that as the CW Interferer power increases, all other signals will lose fidelity. For measurements that need both high dynamic range and high-fidelity low power signals, an instrument with a second RF Channel is recommended.

When CW Interferer is on, a coupling exists between the RF Output Power Total (in the RF Output block) and the CW Interferer absolute power; if the RF Output Power Total is adjusted lower in amplitude such that Signal Power runs out of range, the level of the absolute power is reduced and a clipping message is displayed.

GUI Location

Adjustments > CW Interferer > CW Interferer Power > Control Mode (Absolute) > Absolute

SCPI Command

[:SOURce]:IQOut<channel>:CWINterferer:POWer:ABSolute <ampl>

[:SOURce]:IQOut<channel>:CWINterferer:POWer:ABSolute?

SCPI Example

IQO:CWIN:POW:ABS -1

IQO:CWIN:POW:ABS?

Preset

-96 dBm

State Saved

Yes

Min

-120 dBm

Max

23 dBm (limited by max power options; cannot be higher than settable power)

See max value of Power (Total RMS).

Resolution

0.01 dB

Step Increment

5 dB

Total Power

Applies to N5186A only.

Displays the sum of CW interferer power (assumed to be on), AWGN power (if on), and the signal block's power.

No SCPI command available for this feature.