Keysight M8195A Revision 2 – Arbitrary Waveform Generator
User’s Guide
8 Appendix
8.1 Resampling Algorithms for Waveform Import / 263
8.1 Resampling Algorithms for Waveform Import
8.1.1 Resampling Requirements
Resampling is typically associated to a series of processes applied to a waveform
sampled at a given sampling frequency to generate a new waveform with a different
sampling rate while preserving all the original information contained in the signal
within the Nyquist bandwidth corresponding to the output sampling rate. Processes
involved in resampling may vary depending on the output to input sampling rate ratio
(or resampling factor) and the integer nature of the ratio itself. Resampling
calculations, when applied to arbitrary waveform generation, must meet additional
constraints such as available record length boundaries, record length granularity
requirements, or acceptable sampling rate range.
Typically, the characteristics of the input waveform (sampling rate, record length) are
externally defined (i.e. by the horizontal settings of an oscilloscope used to capture
the waveform). Users may be interested in resampling the signal to adapt the input
waveform to the AWG requirements or the user desires. In some cases, it may be
necessary to reduce the sampling rate if it has been captured at a higher sampling
rate than the one allowed by the AWG or to reduce the record length required to
generate it. The opposite is also true as oversampling may help to “smooth” the
signal as increasing sampling rate will shift the images created by the DAC to a
higher frequency. Finally, resampling may be also necessary to adapt the record
length of the input waveform to a legal record length that can be applied to a real
AWG (i.e. to meet the record length granularities) without applying truncation or
“zero padding” to the input waveform.
To Next Page
Loading...
