Kennard White is the author of X-pole, an interactive analog and digital
filter design program.
X-pole supports classical analog/digital IIR filter design techniques,
proportional-integral-differential (PID) feedback control filters,
window-based digital FIR filter design,
and Parks-McClellan digital FIR filter design.
X-pole is a combination of Tcl/Tk code and C routines
written by Kennard White.
It is currently not supported by the Ptolemy Group, but parts
of it may be integrated into the Tycho user interface being developed
for the Ptolemy software environment.
- Kennard D. White,
An Interactive Graphical Signal Analysis and Filter Design Tool,
MS Report, UCB/ERL M93/70, Dept. of EECS, University of California,
Berkeley, CA 94720, May 1993.
XPole sources are
available via anonymous ftp from
(Note that Xpole uses Tcl 6.x and Tk3.x, so it may not work with Tcl7.x and Tk4.x)
- PtFilter, a Java prototype that
may replace X-pole.
Last updated 05/04/98.
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