Filter- and DSP-Links  

DSP FAQ http://www.bdti.com/faq/dsp_faq.htm
EG3.com - DSP and Communications http://www.cera2.com/dsp/index.htm
Rice University - DSP Group http://www-dsp.rice.edu
Charles Poynton DSP Links http://www.poynton.com/notes/links/dsp-links.html
DSP DesignLine http://www.dspdesignline.com
Steven W. Smith DSP Guide http://www.dspguide.com
Connexions http://cnx.org
Mathtools.net http://www.mathtools.net
Scicos Home Page http://www.scicos.org