niUSRP Fetch Rx Data (2D I16)

Fetches complex, 16-bit signed integer data from the specified channels. To use niUSRP Fetch Rx Data (2D I16), you must set the Host Data Type property to I16.

Inputs/Outputs

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session handle

Instrument session.

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error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Default value: No error

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number of samples

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.
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timeout

Time to wait, in seconds, before returning an error if the requested number of samples have not been acquired.

Default value: 10

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channel list

Channel(s) from which to fetch the data.

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session handle out

Reference to your instrument session to be passed to the next node.

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error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

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data

Received baseband samples as an array of complex, 16-bit signed integer data.

The real and imaginary components of the data correspond to the in-phase (I) and quadrature-phase (Q) data, respectively. I and Q are interleaved [I, Q, I, Q, ...] in the array. The total number of elements returned in the array equals (the value of the number of samples input x 2) 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 Configure Signal.

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timestamp

Timestamp of the first receive (Rx) sample returned and the time associated with the first sample of the waveform, according to the onboard device timer.

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whole seconds

Integer number of seconds for the time associated with the first sample of the waveform, according to the onboard device timer.

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fractional seconds

Double-precision, floating-point value representing the remaining fraction of a second for the time associated with the first sample of the waveform, according to the onboard device timer.

Hardware Support

This node supports the following hardware:

  • USRP-2900/2901
  • USRP-2920/2921/2922
  • USRP-2930/2932
  • USRP-2940/2942/2943/2944/2945
  • USRP-2950/2952/2953/2954/2955