niUSRP Fetch Rx Data (2D CDB) VI
- Updated2024-10-14
- 4 minute(s) read
Fetches complex, double-precision floating-point data from the specified channels.

Inputs/Outputs
channel list
—
channel list specifies the channel(s) from which to fetch the data.
session handle
—
session handle identifies your instrument session. session handle is obtained from the niUSRP Open Rx Session VI and identifies a particular receive (Rx) session.
number of samples
—
number of samples specifies the number of samples to fetch from the acquisition channel. For finite acquisitions, if you specify a value of -1, NI-USRP returns all the remaining samples. NI-USRP returns the samples when the requested number of samples is retrieved from the device or when the timeout is exceeded, whichever happens first.
timeout
—
timeout specifies the time to wait, in seconds, before returning an error if the requested number of samples have not been acquired. A negative value indicates to the driver to wait indefinitely.
error in (no error)
—
error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
session handle out
—
session handle out passes a reference to your instrument session to the next VI. session handle out is obtained from the niUSRP Open Rx Session VI and identifies a particular receive (Rx) session.
data
—
data returns the received baseband samples as an array of complex, double-precision floating-point data. The real and imaginary parts of this complex data array correspond to the in-phase (I) and quadrature-phase (Q) data, respectively. The total number of elements returned in the array equals the value of the number of samples input x the number of channels. Each row of the 2D array corresponds to a separate channel. The time between samples in the waveform (the sample period) equals 1 divided by the coerced I/Q rate. Determine the coerced I/Q rate by reading the IQ Rate property after you set it or by reading the coerced IQ rate output of the Configure Signal VI.
timestamp
—
timestamp returns the timestamp of the first receive (Rx) sample returned and indicates the time associated with the first sample of the waveform, according to the onboard device timer. timestamp is the time of the clock in seconds, interpreted as whole seconds.fractional seconds.
error out
—
error out contains error information. This output provides standard error out functionality. |
channel list
—
session handle
—
number of samples
—
timeout
—
error in (no error)
—
session handle out
—
data
—
timestamp
—
whole seconds
—
fractional seconds
—
error out
—