Digital Filter Plus™ 

One license covers both
Windows and Linux

License fee includes
free upgrade and support

Finite Impulse Response Filters
Windowing
Parks-McClellan Remez Exchange Algorithm
Hilbert Transform
Raised Cosine
Square Root Raised Cosine
Gaussian

Infinite Impulse Response Filters
Pole Zero Placement
Butterworth
Chebyschev
Inverse Chebyschev
Elliptic
Bessel
Bilinear transform
Matched z-transform
Notch Filters

Digital Filter Plus is an Finite Impulse Response (FIR) and Infinite Impulse Response (IIR) digital filter design program that runs under Windows™ and Linux™. The following screen shots show DFPlus in use :
FIR low pass filter magnitude
FIR low pass filter phase
IIR band pass filter magnitude
IIR band pass filter phase

The following packages include the complete filter design toolset, which can be used for free in demonstration mode. The demonstration mode does not allow allow the filter coefficients to be saved to disk but this feature is enabled by the purchase of a developer's license.

Download Digital Filter Plus for Windows ™
Download Digital Filter Plus for Linux ™

Digital Filter Plus has been developed using the SigLib DSP Library and the excellent (and free) wxWindows cross platform development library. We thoroughly recommend wxWindows, it is a very powerful tool that allows programs to run on different operating systems with just a simple re-compile.

Digital Filter Plus Documentation