niRFSA Read Power Spectrum (Cluster)

NI RF Vector Signal Analyzers

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niRFSA Read Power Spectrum (Cluster)

Initiates a spectrum acquisition and returns power spectrum data.

instrument handle identifies your instrument session. instrument handle is obtained from the niRFSA Initialize or the niRFSA Initialize With Options VIs and identifies a particular instrument session.

timeout specifies in seconds the time allotted for the function to complete before returning a timeout error. A value of -1 specifies the VI waits until all data is available.

error in (no error) describes error conditions that occur before this VI runs.

	status is TRUE (X) if an error occurred before this VI ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI ran. The default is FALSE.
	code is the error or warning code. The default is 0. If status is TRUE, code is a negative error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI that produced the error or warning. The default is an empty string.

instrument handle out passes a reference to your instrument session to the next VI. instrument handle is obtained from the niRFSA Initialize or the niRFSA Initialize With Options VIs and identifies a particular instrument session.

power spectrum returns power spectrum data.

f0 returns the start frequency of the spectrum, expressed in Hertz.

df returns the frequency interval between data points in the spectrum, expressed in Hertz

data returns the acquired data as a cluster.

	t0 returns the trigger (start) time of the acquired signal.
	dt returns the time interval between data points in the acquired signal. The IQ data sampling rate is the reciprocal of this value.
	Y returns the complex-valued time domain data array. The real and imaginary parts of this complex data array correspond to the in-phase (I) and quadrature-phase (Q) data, respectively. To calculate the instantaneous power of a sampled IQ point, use the equation (I ² + Q ²)/2R, where R is the input impedance in ohms. For NI RF signal analyzers, R = 50 ohms.

error out contains error information. If error in indicates that an error occurred before this VI ran, error out contains the same error information. Otherwise, it describes the error status that this VI produces.

	status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
	code the error or warning code. If status is TRUE, code is a non-zero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI that produced the error or warning.

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