Factorable FIR Nyquist filters with least stopband energy under sidelobe level constraints
M. Liu, Christopher J. Zarowski, Frederick W. Fairman · IEEE Transactions on Signal Processing · 2000
Spectrally factorable Nyquist filters are used in data communications to avoid intersymbol interference. An approach is developed for obtaining a Nyquist filter that is factorable having the smallest stopband energy for a given sidelobe level. The resulting constrained minimization problem is solved efficiently and reliably using the Goldfarb-Idnani (1983) algorithm. Some examples are presented comparing the present method with a previous approach from the literature.