MT Resample (Complex Cluster) VI

LabView Analog Modulation

MT Resample (Complex Cluster) VI

Specifies a complex-valued waveform and resamples and/or realigns it based on the input parameters that you specify.

MT Resample (Complex Cluster)

initial sample offset specifies the initial sample offset, in seconds. This positive value specifies the location in time of the first output point relative to the first input point. The default is 0.00.

input complex waveform specifies the complex baseband waveform data.

	t0 specifies the trigger (start) time of the Y array. The default is 0.00.
	dt specifies time interval between data points in the Y array. The default is 1.00.
	Y specifies 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.

desired sample rate specifies the desired sample rate of the output complex waveform data, in hertz. This value can be an integer or a noninteger multiple of the input data sample rate. The default is 1.00.

reset? controls whether the VI continues resampling using the previous iteration states. reset? must be set to TRUE whenever you want to restart fractional resampling. The default is TRUE.

flush buffers? forces out samples that are delayed because of the FIR filters used in the resampling algorithm. Set this parameter TRUE during single-shot operations or during the last iteration of continuous operations. The default is FALSE.

Note Setting flush buffers? to TRUE destroys the internal states of the algorithms such that you cannot perform continuous processing on the signal during subsequent iterations. If flush buffers? is set to TRUE, you must set reset? to TRUE on the subsequent iteration.

error in (no error) accepts error information wired from previously called VIs. Use this information to decide if any functionality should be bypassed in the event of errors from other VIs. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.

	status is either TRUE (X) for an error, or FALSE (checkmark) for no error or a warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.
	code identifies the error or warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.
	source describes the origin of the error or warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.

output complex waveform returns the resampled complex baseband waveform data.

	t0 returns the time of first value in Y array.
	dt returns the time between values in the Y array.
	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.

error out passes error or warning information out of a VI to be used by other VIs. Right-click the front panel error out indicator and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.

	status is either TRUE (X) for an error, or FALSE (checkmark) for no error or a warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.
	code identifies the error or warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.
	source describes the origin of the error or warning. Right-click the front panel error in control and select Explain Error or Explain Warning from the shortcut menu for more information about the error displayed.

Details

To realign the input waveform in time, specify a nonzero value to the initial sample offset parameter. Positive (negative values are invalid) offset values push the output complex waveform forward relative to the input complex waveform.

To resample a waveform, specify a desired sample rate that differs from the existing sample rate of the input complex waveform. To realign a waveform without changing its sample rate, specify a value for the desired sample rate parameter equal to the existing sample rate. To resample a waveform without changing the relative timing offset between the input and output complex waveforms, specify initial sample offset parameter as 0.

Using MT Fractional Resample in Modulation Toolkit 4.1

The Modulation Toolkit 4.0 version of MT Fractional Resample VI has been deprecated for Modulation Toolkit 4.1. If your application currently uses the MT Fractional Resample VI, the application continues to refer to the Modulation Toolkit 4.0 version of the MT Fractional Resample VI located at <LabVIEW>\vi.lib\addons\Modulation\Analog\Deprecated. Use the MT Resample (Complex Cluster) VI for Modulation Toolkit 4.1 or later applications.

Note The FIR filters used in the resampling algorithms in the MT Resample (Complex Cluster) and the MT Fractional Resample VIs have different delays. If your application depends on the specific filter delay value of the MT Fractional Resample VI, review your application and evaluate if you can use the MT Resample (Complex Cluster) VI with the flush buffers? parameter set to TRUE instead. To switch to using the MT Resample (Complex Cluster), replace the MT Fractional Resample with this VI and carefully review and modify the parts of your application that depend on specific values of filter delays.

Because of the difference in the FIR filters, comparing data from the MT Fractional Resample VI and MT Resample (Complex Cluster) VI does not produce numerically exact matches.

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