Editing Sampling (signal processing) (section)

== Undersampling ==
{{Main|Undersampling}}

When a [[bandpass]] signal is sampled slower than its [[Nyquist rate]], the samples are indistinguishable from samples of a low-frequency [[aliasing|alias]] of the high-frequency signal. That is often done purposefully in such a way that the lowest-frequency alias satisfies the [[Nyquist rate|Nyquist criterion]], because the bandpass signal is still uniquely represented and recoverable. Such [[undersampling]] is also known as ''bandpass sampling'', ''harmonic sampling'', ''IF sampling'', and ''direct IF to digital conversion.''<ref>
{{cite book
 | title = Mixed-signal and DSP design techniques
 | author = Walt Kester
 | publisher = Newnes
 | year = 2003
 | isbn = 978-0-7506-7611-3
 | page = 20
 | url = https://books.google.com/books?id=G8XyNItpy8AC&pg=PA20
 | access-date = 8 January 2014
 }}</ref>