NI RFmx SpecAn General Attributes

General Attributes

• RFMXSPECAN_ATTR_SELECTED_PORTS
• RFMXSPECAN_ATTR_CENTER_FREQUENCY
• RFMXSPECAN_ATTR_REFERENCE_LEVEL
• RFMXSPECAN_ATTR_EXTERNAL_ATTENUATION
• RFMXSPECAN_ATTR_REFERENCE_LEVEL_HEADROOM
• RFMXSPECAN_ATTR_RESULT_FETCH_TIMEOUT

RFMXSPECAN_ATTR_SELECTED_PORTS

Data Type:	char []
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeString RFmxSpecAn_GetAttributeString
Description:	Specifies the instrument port to be configured to acquire a signal. Use RFmxInstr_GetAvailablePorts function to get the valid port names. 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. Valid values PXIe-5830 if0, if1 PXIe-5831/5832 if0, if1, rf(0-1)/port(x), where 0-1 indicates one (0) or two (1) mmRH-5582 connections and x is the port number on the mmRH-5582 front panel Other devices '' (empty string) Default values PXIe-5830/5831/5832 if1 Other devices '' (empty string) Get Function: RFmxSpecAn_GetSelectedPorts Set Function: RFmxSpecAn_SetSelectedPorts

RFMXSPECAN_ATTR_CENTER_FREQUENCY

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the expected carrier frequency of the RF signal that needs to be acquired. This value is expressed in Hz. The signal analyzer tunes to this frequency. 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 of this attribute is hardware dependent. Get Function: RFmxSpecAn_GetCenterFrequency Set Function: RFmxSpecAn_SetCenterFrequency

RFMXSPECAN_ATTR_REFERENCE_LEVEL

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the reference level which represents the maximum expected power of the RF input signal. This value is configured in dBm for RF devices and as Vpk-pk for baseband devices. 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 of this attribute is hardware dependent. Get Function: RFmxSpecAn_GetReferenceLevel Set Function: RFmxSpecAn_SetReferenceLevel

RFMXSPECAN_ATTR_EXTERNAL_ATTENUATION

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the attenuation of a switch (or cable) connected to the RF IN connector of the signal analyzer. This value is expressed in dB. For more information about attenuation, refer to the Attenuation and Signal Levels topic for your device in the NI RF Vector Signal Analyzers Help. 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. Get Function: RFmxSpecAn_GetExternalAttenuation Set Function: RFmxSpecAn_SetExternalAttenuation

RFMXSPECAN_ATTR_REFERENCE_LEVEL_HEADROOM

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the margin RFmx adds to the RFMXSPECAN_ATTR_REFERENCE_LEVEL attribute. The margin avoids clipping and overflow warnings if the input signal exceeds the configured reference level. RFmx configures the input gain to avoid clipping and associated overflow warnings provided the instantaneous power of the input signal remains within the RFMXSPECAN_ATTR_REFERENCE_LEVEL plus the RFMXSPECAN_ATTR_REFERENCE_LEVEL_HEADROOM. If you know the input power of the signal precisely or previously included the margin in the RFMXSPECAN_ATTR_REFERENCE_LEVEL, you could improve the signal-to-noise ratio by reducing the RFMXSPECAN_ATTR_REFERENCE_LEVEL_HEADROOM. 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. Supported devices: PXIe-5668, PXIe-5830/5831/5832/5840/5841. Default values PXIe-5668 6 dB PXIe-5830/5831/5832/5841 1 dB PXIe-5840 0 dB Get Function: RFmxSpecAn_GetReferenceLevelHeadroom Set Function: RFmxSpecAn_SetReferenceLevelHeadroom

RFMXSPECAN_ATTR_RESULT_FETCH_TIMEOUT

Data Type:	float64
Access:	read/write
Functions:	RFmxSpecAn_SetAttributeF64 RFmxSpecAn_GetAttributeF64
Description:	Specifies the time, in seconds, to wait before results are available in the RFmxSpecAn_AttributeNode. Set this value to a time longer than expected for fetching the measurement. A value of -1 specifies that the RFmxSpecAn Attribute Node waits until the measurement is complete. 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_GetResultFetchTimeout Set Function: RFmxSpecAn_SetResultFetchTimeout