Ultraspherical Windows

Routines to calculate discrete-time and sampled continuous-time ultraspherical windows

This package includes routines to calculate discrete-time ultraspherical and sampled continuous-time ultraspherical windows. The discrete-time ultraspherical windows include Dolph-Chebyshev and Saramäki windows as special cases. For the discrete-time windows, new algorithms based on the ultraspherical polynomial recurrence relationship are implemented - these avoid the need to use trigonometric functions.

For sampled continuous-time ultraspherical windows (Dolph-Chebyshev and Kaiser-Bessel windows as special cases), a series expansion is used to compute the samples. Of note is a new procedure to set the end-points of the sampled continuous-time Dolph-Chebyshev window in such a way as to give a frequency response which is nearly equiripple in the stopband.