Search Mathematics of the DFT
Book Index | Global Index
Would you like to be notified by email when Julius Orion Smith III publishes a new entry into his blog?
Shift Operator
The shift operator is defined by
and

denotes the entire shifted
signal. Note that
since indexing is modulo

, the shift is
circular (or
``cyclic''). However, we normally use it to represent
time
delay by

samples. We often use the shift operator in
conjunction with
zero padding (appending zeros to the signal

, §
7.2.7) in order to avoid the ``wrap-around''
associated with a circular shift.
Figure 7.2:
Successive one-sample shifts of a
sampled periodic sawtooth waveform having first period
.
![\includegraphics[width=\twidth]{eps/shift}](http://www.dsprelated.com/josimages/mdft/img1150.png) |
Figure 7.2 illustrates successive one-sample delays of a periodic signal
having first period given by
.
Subsections
Previous:
Flip OperatorNext:
Examples
written by Julius Orion Smith III
Julius Smith's background is in electrical engineering (BS Rice 1975, PhD Stanford 1983). He is presently Professor of Music and Associate Professor (by courtesy) of Electrical Engineering at
Stanford's Center for Computer Research in Music and Acoustics (CCRMA), teaching courses and pursuing research related to signal processing applied to music and audio systems. See
http://ccrma.stanford.edu/~jos/ for details.