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Alex Starche edited this page Feb 28, 2022 · 4 revisions

IM Attributes

RFMXSPECAN_ATTR_IM_MEASUREMENT_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to enable the IM measurement.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_FALSE.

Get Function: RFmxSpecAn_IMGetMeasurementEnabled
Set Function: RFmxSpecAn_IMSetMeasurementEnabled

RFMXSPECAN_ATTR_IM_FREQUENCY_DEFINITION

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the tones and intermod frequencies are relative to the RF center frequency, or are absolute frequencies.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_FREQUENCY_DEFINITION_RELATIVE.

Get Function: RFmxSpecAn_IMGetFrequencyDefinition
Set Function: RFmxSpecAn_IMSetFrequencyDefinition
Values:
RFMXSPECAN_VAL_IM_FREQUENCY_DEFINITION_RELATIVE (0) The tone and intermod frequencies are relative to the RF center frequency.
RFMXSPECAN_VAL_IM_FREQUENCY_DEFINITION_ABSOLUTE (1) The tone and intermod frequencies are absolute frequencies. The measurement ignores the RF center frequency.

IM Fundamental

RFMXSPECAN_ATTR_IM_FUNDAMENTAL_LOWER_TONE_FREQUENCY

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the frequency of the tone that has a lower frequency among the two tones in the input signal. This value is expressed in Hz.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is -1 MHz.

Get Function: RFmxSpecAn_IMGetFundamentalLowerToneFrequency
Set Function: RFmxSpecAn_IMSetFundamentalLowerToneFrequency

RFMXSPECAN_ATTR_IM_FUNDAMENTAL_UPPER_TONE_FREQUENCY

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the frequency of the tone that has a higher frequency among the two tones in the input signal. This value is expressed in Hz.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 1 MHz.

Get Function: RFmxSpecAn_IMGetFundamentalUpperToneFrequency
Set Function: RFmxSpecAn_IMSetFundamentalUpperToneFrequency

RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the measurement computes the intermod frequencies or uses user-specified frequencies.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Get Function: RFmxSpecAn_IMGetAutoIntermodsSetupEnabled
Set Function: RFmxSpecAn_IMSetAutoIntermodsSetupEnabled
Values:
RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_FALSE (0) The measurement uses the values that you specify for the RFMXSPECAN_ATTR_IM_LOWER_INTERMOD_FREQUENCY and RFMXSPECAN_ATTR_IM_UPPER_INTERMOD_FREQUENCY attributes.
RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE (1) The measurement computes the intermod frequencies. The maximum number of intermods that you can measure is based on the value of the RFMXSPECAN_ATTR_IM_MAXIMUM_INTERMOD_ORDER attribute.

RFMXSPECAN_ATTR_IM_MAXIMUM_INTERMOD_ORDER

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the order up to which the RFmx driver measures odd order intermodulation products when you set the Auto Intermods Setup Enabled attribute to True. The lower and upper intermodulation products are measured for each order.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 3.

Get Function: RFmxSpecAn_IMGetMaximumIntermodOrder
Set Function: RFmxSpecAn_IMSetMaximumIntermodOrder

IM Intermod

RFMXSPECAN_ATTR_IM_NUMBER_OF_INTERMODS

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the number of intermods to measure when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_FALSE.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 1.

Get Function: RFmxSpecAn_IMGetNumberOfIntermods
Set Function: RFmxSpecAn_IMSetNumberOfIntermods

RFMXSPECAN_ATTR_IM_INTERMOD_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to enable an intermod for the IM measurement. This attribute is not used when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Use 'intermod(n)' as the selector string to configure or read this attribute.

The default value is RFMXSPECAN_VAL_IM_INTERMOD_ENABLED_TRUE.

Get Function: RFmxSpecAn_IMGetIntermodEnabled
Set Function: RFmxSpecAn_IMSetIntermodEnabled
Values:
RFMXSPECAN_VAL_IM_INTERMOD_ENABLED_FALSE (0) Disables an intermod for the IM measurement. The results for the disabled intermods are displayed as NaN.
RFMXSPECAN_VAL_IM_INTERMOD_ENABLED_TRUE (1) Enables an intermod for the IM measurement.

RFMXSPECAN_ATTR_IM_INTERMOD_ORDER

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the order of the intermod. This attribute is not used when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Use 'intermod(n)' as the selector string to configure or read this attribute.

The default value is 3.

Get Function: RFmxSpecAn_IMGetIntermodOrder
Set Function: RFmxSpecAn_IMSetIntermodOrder

RFMXSPECAN_ATTR_IM_INTERMOD_SIDE

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to measure intermodulation products corresponding to both lower and upper intermod frequencies or either one of them. This attribute is not used when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Use 'intermod(n)' as the selector string to configure or read this attribute.

The default value is RFMXSPECAN_VAL_IM_INTERMOD_SIDE_BOTH.

Get Function: RFmxSpecAn_IMGetIntermodSide
Set Function: RFmxSpecAn_IMSetIntermodSide
Values:
RFMXSPECAN_VAL_IM_INTERMOD_SIDE_LOWER (0) Measures the intermodulation product corresponding to the RFMXSPECAN_ATTR_IM_LOWER_INTERMOD_FREQUENCY attribute.
RFMXSPECAN_VAL_IM_INTERMOD_SIDE_UPPER (1) Measures the intermodulation product corresponding to the RFMXSPECAN_ATTR_IM_UPPER_INTERMOD_FREQUENCY attribute.
RFMXSPECAN_VAL_IM_INTERMOD_SIDE_BOTH (2) Measures the intermodulation product corresponding to both RFMXSPECAN_ATTR_IM_LOWER_INTERMOD_FREQUENCY and RFMXSPECAN_ATTR_IM_UPPER_INTERMOD_FREQUENCY attributes.

RFMXSPECAN_ATTR_IM_LOWER_INTERMOD_FREQUENCY

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the frequency of the lower intermodulation product. This value is expressed in Hz. This attribute is not used when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Use 'intermod(n)' as the selector string to configure or read this attribute.

The default value is -3 MHz.

Get Function: RFmxSpecAn_IMGetLowerIntermodFrequency
Set Function: RFmxSpecAn_IMSetLowerIntermodFrequency

RFMXSPECAN_ATTR_IM_UPPER_INTERMOD_FREQUENCY

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the frequency of the upper intermodulation product. This value is expressed in Hz. This attribute is not used when you set the RFMXSPECAN_ATTR_IM_AUTO_INTERMODS_SETUP_ENABLED attribute to RFMXSPECAN_VAL_IM_AUTO_INTERMODS_SETUP_ENABLED_TRUE.

Use 'intermod(n)' as the selector string to configure or read this attribute.

The default value is 3 MHz.

Get Function: RFmxSpecAn_IMGetUpperIntermodFrequency
Set Function: RFmxSpecAn_IMSetUpperIntermodFrequency

RFMXSPECAN_ATTR_IM_MEASUREMENT_METHOD

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the method used to perform the IM measurement.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_NORMAL.

Get Function: RFmxSpecAn_IMGetMeasurementMethod
Set Function: RFmxSpecAn_IMSetMeasurementMethod
Values:
RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_NORMAL (0) The IM measurement acquires the spectrum using the same signal analyzer settings across frequency bands. Use this method when the fundamental tone separation is not large. Supported devices: PXIe-5644/5645/5646/5840/5841/5830/5831/5832, PXIe-5663/5665/5668.
RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_DYNAMIC_RANGE (1) The IM measurement acquires a segmented spectrum using the signal analyzer specific optimizations for different frequency bands. The spectrum is acquired in segments, one per tone or intermod frequency to be measured. The span of each acquired spectral segment is equal to the frequency separation between the two input tones, or 1 MHz, whichever is smaller. Use this method to configure the IM measurement and the signal analyzer for maximum dynamic range instead of measurement speed. Supported devices: PXIe-5665/5668.
RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_SEGMENTED (2) Similar to the Dynamic Range method, this method also acquires a segmented spectrum, except that signal analyzer is not explicitly configured to provide maximum dynamic range. Use this method when the frequency separation of the two input tones is large and the measurement accuracy can be traded off for measurement speed. Supported devices: PXIe-5644/5645/5646/5840/5841/5830/5831/5832, PXIe-5663/5665/5668.

RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to enable a local peak search around the tone or intermod frequencies to account for small frequency offsets.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE.

Get Function: RFmxSpecAn_IMGetLocalPeakSearchEnabled
Set Function: RFmxSpecAn_IMSetLocalPeakSearchEnabled
Values:
RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_FALSE (0) The measurement returns the power at the tone and intermod frequencies.
RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE (1) The measurement performs a local peak search around the tone and intermod frequencies to return the peak power.

IM RBW Filter

RFMXSPECAN_ATTR_IM_RBW_FILTER_AUTO_BANDWIDTH

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the measurement computes the RBW.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_RBW_FILTER_AUTO_BANDWIDTH_TRUE.

Get Function: RFmxSpecAn_IMGetRBWFilterAutoBandwidth
Set Function: RFmxSpecAn_IMSetRBWFilterAutoBandwidth
Values:
RFMXSPECAN_VAL_IM_RBW_FILTER_AUTO_BANDWIDTH_FALSE (0) The measurement uses the RBW that you specify in the RFMXSPECAN_ATTR_IM_RBW_FILTER_BANDWIDTH attribute.
RFMXSPECAN_VAL_IM_RBW_FILTER_AUTO_BANDWIDTH_TRUE (1) The measurement computes the RBW.

RFMXSPECAN_ATTR_IM_RBW_FILTER_BANDWIDTH

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the bandwidth of the RBW filter used to sweep the acquired signal, when you set the RFMXSPECAN_ATTR_IM_RBW_FILTER_AUTO_BANDWIDTH attribute to RFMXSPECAN_VAL_IM_RBW_FILTER_AUTO_BANDWIDTH_FALSE. This value is expressed in Hz.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 10 kHz.

Get Function: RFmxSpecAn_IMGetRBWFilterBandwidth
Set Function: RFmxSpecAn_IMSetRBWFilterBandwidth

RFMXSPECAN_ATTR_IM_RBW_FILTER_TYPE

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the response of the digital RBW filter.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_RBW_FILTER_TYPE_GAUSSIAN.

Get Function: RFmxSpecAn_IMGetRBWFilterType
Set Function: RFmxSpecAn_IMSetRBWFilterType
Values:
RFMXSPECAN_VAL_IM_RBW_FILTER_TYPE_FFT_BASED (0) No RBW filtering is performed.
RFMXSPECAN_VAL_IM_RBW_FILTER_TYPE_GAUSSIAN (1) An RBW filter with a Gaussian response is applied.
RFMXSPECAN_VAL_IM_RBW_FILTER_TYPE_FLAT (2) An RBW filter with a flat response is applied.

IM Sweep Time

RFMXSPECAN_ATTR_IM_SWEEP_TIME_AUTO

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the measurement computes the sweep time.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_SWEEP_TIME_AUTO_TRUE.

Get Function: RFmxSpecAn_IMGetSweepTimeAuto
Set Function: RFmxSpecAn_IMSetSweepTimeAuto
Values:
RFMXSPECAN_VAL_IM_SWEEP_TIME_AUTO_FALSE (0) The measurement uses the sweep time that you specify in the RFMXSPECAN_ATTR_IM_SWEEP_TIME_INTERVAL attribute.
RFMXSPECAN_VAL_IM_SWEEP_TIME_AUTO_TRUE (1) The measurement computes the sweep time based on the value of the RFMXSPECAN_ATTR_IM_RBW_FILTER_BANDWIDTH attribute.

RFMXSPECAN_ATTR_IM_SWEEP_TIME_INTERVAL

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the sweep time when you set the RFMXSPECAN_ATTR_IM_SWEEP_TIME_AUTO attribute to RFMXSPECAN_VAL_IM_SWEEP_TIME_AUTO_FALSE. This value is expressed in seconds.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 0.001.

Get Function: RFmxSpecAn_IMGetSweepTimeInterval
Set Function: RFmxSpecAn_IMSetSweepTimeInterval

IM Averaging

RFMXSPECAN_ATTR_IM_AVERAGING_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to enable averaging for the IM measurement.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_AVERAGING_ENABLED_FALSE.

Get Function: RFmxSpecAn_IMGetAveragingEnabled
Set Function: RFmxSpecAn_IMSetAveragingEnabled
Values:
RFMXSPECAN_VAL_IM_AVERAGING_ENABLED_FALSE (0) The measurement is performed on a single acquisition.
RFMXSPECAN_VAL_IM_AVERAGING_ENABLED_TRUE (1) The IM measurement uses the RFMXSPECAN_ATTR_IM_AVERAGING_COUNT attribute as the number of acquisitions over which the IM measurement is averaged.

RFMXSPECAN_ATTR_IM_AVERAGING_COUNT

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the number of acquisitions used for averaging when you set the RFMXSPECAN_ATTR_IM_AVERAGING_ENABLED attribute to RFMXSPECAN_VAL_IM_AVERAGING_ENABLED_TRUE.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 10.

Get Function: RFmxSpecAn_IMGetAveragingCount
Set Function: RFmxSpecAn_IMSetAveragingCount

RFMXSPECAN_ATTR_IM_AVERAGING_TYPE

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the averaging type for averaging multiple spectrum acquisitions. The averaged spectrum is used for the IM measurement.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_AVERAGING_TYPE_RMS.

Get Function: RFmxSpecAn_IMGetAveragingType
Set Function: RFmxSpecAn_IMSetAveragingType
Values:
RFMXSPECAN_VAL_IM_AVERAGING_TYPE_RMS (0) The power spectrum is linearly averaged. RMS averaging reduces signal fluctuations but not the noise floor.
RFMXSPECAN_VAL_IM_AVERAGING_TYPE_LOG (1) The power spectrum is averaged in a logarithmic scale.
RFMXSPECAN_VAL_IM_AVERAGING_TYPE_SCALAR (2) The square root of the power spectrum is averaged.
RFMXSPECAN_VAL_IM_AVERAGING_TYPE_MAXIMUM (3) The peak power in the spectrum at each frequency bin is retained from one acquisition to the next.
RFMXSPECAN_VAL_IM_AVERAGING_TYPE_MINIMUM (4) The least power in the spectrum at each frequency bin is retained from one acquisition to the next.

IM FFT

RFMXSPECAN_ATTR_IM_FFT_WINDOW

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the FFT window type to use to reduce spectral leakage.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_FFT_WINDOW_FLAT_TOP.

Get Function: RFmxSpecAn_IMGetFFTWindow
Set Function: RFmxSpecAn_IMSetFFTWindow
Values:
RFMXSPECAN_VAL_IM_FFT_WINDOW_NONE (0) Analyzes transients for which duration is shorter than the window length. You can also use this window type to separate two tones with frequencies close to each other but with almost equal amplitudes.
RFMXSPECAN_VAL_IM_FFT_WINDOW_FLAT_TOP (1) Measures single-tone amplitudes accurately.
RFMXSPECAN_VAL_IM_FFT_WINDOW_HANNING (2) Analyzes transients for which duration is longer than the window length. You can also use this window type to provide better frequency resolution for noise measurements.
RFMXSPECAN_VAL_IM_FFT_WINDOW_HAMMING (3) Analyzes closely-spaced sine waves.
RFMXSPECAN_VAL_IM_FFT_WINDOW_GAUSSIAN (4) Provides a good balance of spectral leakage, frequency resolution, and amplitude attenuation. This windowing is useful for time-frequency analysis.
RFMXSPECAN_VAL_IM_FFT_WINDOW_BLACKMAN (5) Analyzes single tone because it has a low maximum side lobe level and a high side lobe roll-off rate.
RFMXSPECAN_VAL_IM_FFT_WINDOW_BLACKMAN_HARRIS (6) Useful as a good general purpose window, having side lobe rejection greater than 90 dB and having a moderately wide main lobe.
RFMXSPECAN_VAL_IM_FFT_WINDOW_KAISER_BESSEL (7) Separates two tones with frequencies close to each other but with widely-differing amplitudes.

RFMXSPECAN_ATTR_IM_FFT_PADDING

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the factor by which the time-domain waveform is zero-padded before an FFT. The FFT size is given by the following formula:

FFT size = waveform size * padding

This attribute is used only when the acquisition span is less than the device instantaneous bandwidth.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is -1.

Get Function: RFmxSpecAn_IMGetFFTPadding
Set Function: RFmxSpecAn_IMSetFFTPadding

IM Advanced

RFMXSPECAN_ATTR_IM_IF_OUTPUT_POWER_OFFSET_AUTO

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the measurement computes an IF output power level offset for the intermods to maximize the dynamic range of the signal analyzer. This attribute is used only if you set the RFMXSPECAN_ATTR_IM_MEASUREMENT_METHOD attribute to RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_DYNAMIC_RANGE.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_IF_OUTPUT_POWER_OFFSET_AUTO_TRUE.

Get Function: RFmxSpecAn_IMGetIFOutputPowerOffsetAuto
Set Function: RFmxSpecAn_IMSetIFOutputPowerOffsetAuto
Values:
RFMXSPECAN_VAL_IM_IF_OUTPUT_POWER_OFFSET_AUTO_FALSE (0) The measurement sets the IF output power level offset using the values of the RFMXSPECAN_ATTR_IM_NEAR_IF_OUTPUT_POWER_OFFSET and RFMXSPECAN_ATTR_IM_FAR_IF_OUTPUT_POWER_OFFSET attributes.
RFMXSPECAN_VAL_IM_IF_OUTPUT_POWER_OFFSET_AUTO_TRUE (1) The measurement computes an IF output power level offset for the intermods to improve the dynamic range of the IM measurement.

RFMXSPECAN_ATTR_IM_NEAR_IF_OUTPUT_POWER_OFFSET

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the offset by which to adjust the IF output power level for the intermods near the carrier channel to improve the dynamic range of the signal analyzer. This value is expressed in dB. This attribute is used only if you set the RFMXSPECAN_ATTR_IM_MEASUREMENT_METHOD attribute to RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_DYNAMIC_RANGE and the RFMXSPECAN_ATTR_IM_IF_OUTPUT_POWER_OFFSET_AUTO attribute to RFMXSPECAN_VAL_IM_IF_OUTPUT_POWER_OFFSET_AUTO_FALSE.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 10 dB.

Get Function: RFmxSpecAn_IMGetNearIFOutputPowerOffset
Set Function: RFmxSpecAn_IMSetNearIFOutputPowerOffset

RFMXSPECAN_ATTR_IM_FAR_IF_OUTPUT_POWER_OFFSET

Data Type: float64
Access: read/write
Functions: RFmxSpecAn_SetAttributeF64
RFmxSpecAn_GetAttributeF64
Description: Specifies the offset by which to adjust the IF output power level for the intermods that are far from the carrier channel to improve the dynamic range of the signal analyzer. This value is expressed in dB. This attribute is used only if you set the RFMXSPECAN_ATTR_IM_MEASUREMENT_METHOD attribute to RFMXSPECAN_VAL_IM_MEASUREMENT_METHOD_DYNAMIC_RANGE and the RFMXSPECAN_ATTR_IM_IF_OUTPUT_POWER_OFFSET_AUTO attribute to RFMXSPECAN_VAL_IM_IF_OUTPUT_POWER_OFFSET_AUTO_FALSE.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 20 dB.

Get Function: RFmxSpecAn_IMGetFarIFOutputPowerOffset
Set Function: RFmxSpecAn_IMSetFarIFOutputPowerOffset

RFMXSPECAN_ATTR_IM_ALL_TRACES_ENABLED

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether to enable the traces to be stored and retrieved after performing the IM measurement.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_FALSE.

Get Function: RFmxSpecAn_IMGetAllTracesEnabled
Set Function: RFmxSpecAn_IMSetAllTracesEnabled

RFMXSPECAN_ATTR_IM_AMPLITUDE_CORRECTION_TYPE

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies whether the amplitude of the frequency bins, used in the measurement, is corrected for external attenuation at the RF center frequency, or at the individual frequency bins. Use the RFmxInstr_CfgExternalAttenuationTable function to configure the external attenuation table.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is RFMXSPECAN_VAL_IM_AMPLITUDE_CORRECTION_TYPE_RF_CENTER_FREQUENCY.

Get Function: RFmxSpecAn_IMGetAmplitudeCorrectionType
Set Function: RFmxSpecAn_IMSetAmplitudeCorrectionType
Values:
RFMXSPECAN_VAL_IM_AMPLITUDE_CORRECTION_TYPE_RF_CENTER_FREQUENCY (0) All the frequency bins in the spectrum are compensated with a single external attenuation value that corresponds to the RF center frequency.
RFMXSPECAN_VAL_IM_AMPLITUDE_CORRECTION_TYPE_SPECTRUM_FREQUENCY_BIN (1) An Individual frequency bin in the spectrum is compensated with the external attenuation value corresponding to that frequency.

RFMXSPECAN_ATTR_IM_NUMBER_OF_ANALYSIS_THREADS

Data Type: int32
Access: read/write
Functions: RFmxSpecAn_SetAttributeI32
RFmxSpecAn_GetAttributeI32
Description: Specifies the maximum number of threads used for parallelism for the IM measurement.

The number of threads can range from 1 to the number of physical cores. The number of threads you set may not be used in calculations. The actual number of threads used depends on the problem size, system resources, data availability, and other considerations.

You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector Strings topic for information about the string syntax for named signals.

The default value is 1.

Get Function: RFmxSpecAn_IMGetNumberOfAnalysisThreads
Set Function: RFmxSpecAn_IMSetNumberOfAnalysisThreads

IM Results

IM Results Fundamental

RFMXSPECAN_ATTR_IM_RESULTS_LOWER_TONE_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the peak power measured around the lower tone frequency when you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE. This value is expressed in dBm. When you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_FALSE, the measurement returns the power at the lower tone frequency.

You do not need to use a selector string to read this result for default signal and result instance. Refer to the Selector Strings topic for information about the string syntax for named signals and results.

Get Function: RFmxSpecAn_IMGetResultsFundamentalLowerTonePower

RFMXSPECAN_ATTR_IM_RESULTS_UPPER_TONE_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the peak power measured around the upper tone frequency when you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE. This value is expressed in dBm. When you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_FALSE, the measurement returns the power at the upper tone frequency.

You do not need to use a selector string to read this result for default signal and result instance. Refer to the Selector Strings topic for information about the string syntax for named signals and results.

Get Function: RFmxSpecAn_IMGetResultsFundamentalUpperTonePower

IM Results Intermod

RFMXSPECAN_ATTR_IM_RESULTS_INTERMOD_ORDER

Data Type: int32
Access: read only
Functions: RFmxSpecAn_GetAttributeI32
Description: Returns the order of the intermod.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsIntermodOrder

RFMXSPECAN_ATTR_IM_RESULTS_LOWER_INTERMOD_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the peak power measured around the lower intermod frequency when you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE. This value is expressed in dBm. When you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_FALSE, the measurement returns the power at the lower intermod frequency.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsLowerIntermodPower

RFMXSPECAN_ATTR_IM_RESULTS_UPPER_INTERMOD_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the peak power measured around the upper intermod frequency when you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_TRUE. This value is expressed in dBm. When you set the RFMXSPECAN_ATTR_IM_LOCAL_PEAK_SEARCH_ENABLED attribute to RFMXSPECAN_VAL_IM_LOCAL_PEAK_SEARCH_ENABLED_FALSE, the measurement returns the power at the upper intermod frequency.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsUpperIntermodPower

RFMXSPECAN_ATTR_IM_RESULTS_LOWER_OUTPUT_INTERCEPT_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the lower output intercept power. This value is expressed in dBm. Refer to the IM topic for more information about this result.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsLowerOutputInterceptPower

RFMXSPECAN_ATTR_IM_RESULTS_UPPER_OUTPUT_INTERCEPT_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the upper output intercept power. This value is expressed in dBm. Refer to the IM topic for more information about this result.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsUpperOutputInterceptPower

RFMXSPECAN_ATTR_IM_RESULTS_WORST_CASE_OUTPUT_INTERCEPT_POWER

Data Type: float64
Access: read only
Functions: RFmxSpecAn_GetAttributeF64
Description: Returns the worst case output intercept power which is equal to the minimum of the values of the IM Results Upper Output Intercept Power and IM Results Lower Output Intercept Power results. This value is expressed in dBm.

Use 'intermod(n)' as the selector string to read this result.

Get Function: RFmxSpecAn_IMGetResultsWorstCaseOutputInterceptPower

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