Fetches I/Q data from a single record in an acquisition.

Supported Devices: PXIe-5644/5645/5646, PXI-5661, PXIe-5663/5663E/5665/5667/5668, PXIe-5820/5830/5831/5832/5840/5841/5842/5860


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Inputs/Outputs

  • ci64.png record to fetch —

    record to fetch specifies the record to retrieve. Record numbers are zero-based. The default value is 0.

  • civrn.png instrument handle —

    instrument handle identifies your instrument session. instrument handle is obtained from the niRFSA Initialize VI or the niRFSA Initialize With Options VI.

  • ci64.png samples to read (-1) —

    samples to read specifies the number of samples to fetch. A value of -1 specifies that NI-RFSA fetches all samples. The default value is -1.

    Note Setting samples to read to –1 fetches all remaining samples currently available depending on the Fetch Relative To property and the Fetch Offset property settings.
  • cdbl.png timeout (10 sec) —

    timeout specifies the time, in seconds, allotted for the VI to complete before returning a timeout error for the PXI-5661, PXIe-5663/5665/5667. Specifies the time, in seconds, allotted to receive the reference trigger for the PXIe-5644/5645/5646, PXIe-5668, and PXIe-5820/5830/5831/5832/5840/5841/5842/5860.

    Note A value of -1 specifies that the VI waits until all data is available. A value of 0 specifies the VI immediately returns available data. The default value is 10.
  • cerrcodeclst.png error in —

    error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

  • iivrn.png instrument handle out —

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

  • icclst.png data —

    data returns the acquired data as a cluster.

  • idbl.png t0 —

    t0 returns the start time of the first sample returned. The timestamp corresponds to the difference in seconds between the first sample returned and the Reference Trigger location. The timestamp is zero if the Reference Trigger has not occurred.

    Note The value of t0 returned in data is always 0 for the PXIe-5644/5645/5646.
  • idbl.png dt —

    dt returns the time interval between data points in the acquired signal. The I/Q data sample rate is the reciprocal of this value.

  • i1dcdb.png Y —

    Y returns the complex-value 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 I/Q point, use the equation (I2 + Q2)/2R, where R is the input impedance in ohms (Ω). For vector signal analyzers, R=50 Ω.

    Note The size of the array can vary per record if the Number of Samples property changes per step during RF list mode.
  • inclst.png wfm info —

    wfm info contains the absolute and relative timestamps for the operation, the time interval, and the actual number of samples read.

  • idbl.png absolute timestamp —

    absolute timestamp returns the timestamp, in seconds, of the first fetched sample that is comparable between records and acquisitions. NOTE: The value of the absolute timestamp returned is always 0 for the PXIe-5644/5645/5646, PXIe-5668, and PXIe-5820/5830/5831/5832/5840/5841.

  • idbl.png relative timestamp —

    relative timestamp returns a timestamp that corresponds to the difference, in seconds, between the first sample returned and the Reference Trigger location. The timestamp is zero if the Reference Trigger has not occurred. NOTE: The value of the relative timestamp returned is always 0 for the PXIe-5644/5645/5646.

  • idbl.png dt —

    dt returns the time interval between data points in the acquired signal. The I/Q data sample rate is the reciprocal of this value.

  • ii64.png actual samples read —

    actual samples read returns an integer representing the number of samples in the waveform.

  • idbl.png offset —

    offset returns the offset to scale data, (b), in mx + b form.

  • idbl.png gain —

    gain returns the gain to scale data, (m), in mx + b form.

  • idbl.png reserved1 —

  • idbl.png reserved2 —

  • ierrcodeclst.png error out —

    error out contains error information. This output provides standard error out functionality.