NI RFmx WLAN Fetch TXP Functions

Fetch TXP Functions

• RFmxWLAN_TXPFetchMeasurement
• RFmxWLAN_TXPFetchPowerTrace

RFmxWLAN_TXPFetchMeasurement

int32 __stdcall RFmxWLAN_TXPFetchMeasurement (niRFmxInstrHandle instrumentHandle, char selectorString[], float64 timeout, float64* averagePowerMean, float64* peakPowerMaximum);

Purpose

Returns the average power and the peak power of the signal over which power measurements are performed. Use "segment<n>/chain<k>" as the selector string to read results from this function.

Parameters

Input
Name	Type	Description
instrumentHandle	niRFmxInstrHandle	Specifies the instrument session. The RFmx driver obtains this parameter from the RFmxWLAN_Initialize function.
selectorString	char[]	Specifies a selector string comprising of the signal name, result name, segment number, and chain number. If you do not specify the signal name, the default signal instance is used. If you do not specify the result name, the default result instance is used. Example: "segment0/chain0" "signal::sig1/segment0/chain0" "signal::sig1/result::r1/segment0/chain0" "result::r1/segment0/chain0" You can use the RFmxWLAN_BuildChainString function to build the selector string.
timeout	float64	Specifies the timeout, in seconds, for fetching the specified measurement. Set this value to an appropriate time, longer than expected for fetching the measurement. A value of -1 specifies that the function waits until the measurement is complete.
Output
Name	Type	Description
averagePowerMean	float64*	Returns the average power of the acquired signal. This value is expressed in dBm. When you set the RFMXWLAN_ATTR_TXP_AVERAGING_ENABLED attribute to RFMXWLAN_VAL_TXP_AVERAGING_ENABLED_TRUE, this parameter returns the mean of the average power computed for each averaging count.
peakPowerMaximum	float64*	Returns the peak power of the acquired signal. This value is expressed in dBm. When you set the RFMXWLAN_ATTR_TXP_AVERAGING_ENABLED attribute to RFMXWLAN_VAL_TXP_AVERAGING_ENABLED_TRUE, this parameter returns the maximum of the peak power computed for each averaging count.

Return Value

Name	Type	Description
status	int32	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred. To obtain a text description of the status code and additional information about the error condition, call the RFmxWLAN_GetError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors

RFmxWLAN_TXPFetchPowerTrace

int32 __stdcall RFmxWLAN_TXPFetchPowerTrace (niRFmxInstrHandle instrumentHandle, char selectorString[], float64 timeout, float64* x0, float64* dx, float32 power[], int32 arraySize, int32* actualArraySize);

Purpose

Returns the power versus time trace. Use "segment<n>/chain<k>" as the selector string to read results from this function.

Parameters

Input
Name	Type	Description
instrumentHandle	niRFmxInstrHandle	Specifies the instrument session. The RFmx driver obtains this parameter from the RFmxWLAN_Initialize function.
selectorString	char[]	Specifies a selector string comprising of the signal name, result name, segment number, and chain number. If you do not specify the signal name, the default signal instance is used. If you do not specify the result name, the default result instance is used. Example: "segment0/chain0" "signal::sig1/segment0/chain0" "signal::sig1/result::r1/segment0/chain0" "result::r1/segment0/chain0" You can use the RFmxWLAN_BuildChainString function to build the selector string.
timeout	float64	Specifies the timeout, in seconds, for fetching the specified measurement. Set this value to an appropriate time, longer than expected for fetching the measurement. A value of -1 specifies that the function waits until the measurement is complete.
arraySize	int32	Specifies the size of the array. Set the arraySize parameter to 0 to get the size of all the arrays in the actualArraySize parameter.
Output
Name	Type	Description
x0	float64*	Returns the trace start time. This value is expressed in seconds.
dx	float64*	Returns the sampling interval. This value is expressed in seconds.
power	float32[]	Returns an array of measured signal power. This value is expressed in dBm.
actualArraySize	int32*	Returns the actual size of the array, if you pass NULL to all output array parameters, and set the arraySize parameter to 0.

Return Value

Name	Type	Description
status	int32	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred. To obtain a text description of the status code and additional information about the error condition, call the RFmxWLAN_GetError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors