NI RFmx SpecAn Advanced Attributes

Advanced Attributes

• RFMXSPECAN_ATTR_AUTO_LEVEL_INITIAL_REFERENCE_LEVEL
• RFMXSPECAN_ATTR_LIMITED_CONFIGURATION_CHANGE

RFMXSPECAN_ATTR_AUTO_LEVEL_INITIAL_REFERENCE_LEVEL

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the initial reference level, in dBm, which the RFmxSpecAn_AutoLevel function uses to estimate the peak power of the input signal. 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 30. Get Function: RFmxSpecAn_GetAutoLevelInitialReferenceLevel Set Function: RFmxSpecAn_SetAutoLevelInitialReferenceLevel

RFMXSPECAN_ATTR_LIMITED_CONFIGURATION_CHANGE

Data Type:	int32
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeI32 RFmxSpecAn_GetAttributeI32
Description:	Specifies the set of attributes that are considered by RFmx in the locked signal configuration state. If your test system performs the same measurement at different selected ports, multiple frequencies and/or power levels repeatedly, enabling this attribute will help achieve faster measurements. When you set this attribute to a value other than Disabled, the RFmx driver will use an optimized code path and skip some checks. Because RFmx skips some checks when you use this attribute, you need to be aware of the limitations of this feature, which are listed in the Limitations of the RFMXSPECAN_ATTR_LIMITED_CONFIGURATION_CHANGE Attribute topic. You can also use this attribute to lock a specific instrument configuration for a signal so that every time that you initiate the signal, RFmx applies the RFmxInstr attributes from a locked configuration. NI recommends you use this attribute in conjunction with named signal configurations. Create named signal configurations for each measurement configuration in your test program and set this attribute to a value other than Disabled for one or more of the named signal configurations. This allows RFmx to precompute the acquisition settings for your measurement configurations and re-use the precomputed settings each time you initiate the measurement. You do not need to use this attribute if you create named signals for all the measurement configurations in your test program during test sequence initialization and do not change any RFInstr or personality attributes while testing each device under test. RFmx automatically optimizes that use case. Specify the named signal configuration you are setting this attribute in the selector string input. You do not need to use a selector string to configure or read this attribute for the default signal instance. Refer to the Selector String topic for information about the string syntax for named signals. The default value is RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_DISABLED. Get Function: RFmxSpecAn_GetLimitedConfigurationChange Set Function: RFmxSpecAn_SetLimitedConfigurationChange
Values:

RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_DISABLED (0)	This is the normal mode of RFmx operation. All configuration changes in RFmxInstr attributes or in personality attributes will be applied during RFmx Commit.
RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_NO_CHANGE (1)	Signal configuration and RFmxInstr configuration are locked after the first Commit or Initiate of the named signal configuration. Any configuration change thereafter either in RFmxInstr attributes or personality attributes will not be considered by subsequent RFmx Commits or Initiates of this signal. Use No Change if you have created named signal configurations for all measurement configurations but are setting some RFmxInstr attributes. Refer to the Limitations of the Limited Configuration Change Attribute topic for more details about the limitations of using this mode.
RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_FREQUENCY (2)	Signal configuration, other than center frequency, external attenuation, and RFInstr configuration, is locked after first Commit or Initiate of the named signal configuration. Thereafter, only the Center Frequency and RFMXSPECAN_ATTR_EXTERNAL_ATTENUATION attribute value changes will be considered by subsequent driver Commits or Initiates of this signal. Refer to the Limitations of the Limited Configuration Change Attribute topic for more details about the limitations of using this mode.
RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_REFERENCE_LEVEL (3)	Signal configuration, other than the reference level and RFInstr configuration, is locked after first Commit or Initiate of the named signal configuration. Thereafter only the RFMXSPECAN_ATTR_REFERENCE_LEVEL attribute value change will be considered by subsequent driver Commits or Initiates of this signal. If you have configured this signal to use an IQ Power Edge Trigger, NI recommends that you set the RFMXSPECAN_ATTR_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE to RFMXSPECAN_VAL_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE_RELATIVE so that the trigger level is automatically adjusted as you adjust the reference level. Refer to the Limitations of the Limited Configuration Change Attribute topic for more details about the limitations of using this mode.
RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_FREQUENCY_AND_REFERENCE_LEVEL (4)	Signal configuration, other than center frequency, reference level, external attenuation, and RFInstr configuration, is locked after first Commit or Initiate of the named signal configuration. Thereafter only Center Frequency, RFMXSPECAN_ATTR_REFERENCE_LEVEL, and RFMXSPECAN_ATTR_EXTERNAL_ATTENUATION attribute value changes will be considered by subsequent driver Commits or Initiates of this signal. If you have configured this signal to use an IQ Power Edge Trigger, NI recommends you set the RFMXSPECAN_ATTR_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE to RFMXSPECAN_VAL_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE_RELATIVE so that the trigger level is automatically adjusted as you adjust the reference level. Refer to the Limitations of the Limited Configuration Change Attribute topic for more details about the limitations of using this mode.
RFMXSPECAN_VAL_LIMITED_CONFIGURATION_CHANGE_SELECTED_PORTS_FREQUENCY_AND_REFERENCE_LEVEL (5)	Signal configuration, other than Selected Ports, Center frequency, Reference level, External attenuation, and RFInstr configuration, is locked after first Commit or Initiate of the named signal configuration. Thereafter only Selected Ports, Center Frequency, RFMXSPECAN_ATTR_REFERENCE_LEVEL, and RFMXSPECAN_ATTR_EXTERNAL_ATTENUATION attribute value changes will be considered by subsequent driver Commits or Initiates of this signal. If you have configured this signal to use an IQ Power Edge Trigger, NI recommends you set the RFMXSPECAN_ATTR_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE to RFMXSPECAN_VAL_IQ_POWER_EDGE_TRIGGER_LEVEL_TYPE_RELATIVE so that the trigger level is automatically adjusted as you adjust the reference level. Refer to the Limitations of the Limited Configuration Change Attribute topic for more details about the limitations of using this mode.