An extension of pulse shaping filter theory

The article presents a simple alternative approach to pulse shaping filters with ISI-free matched (white noise case) and unmatched filter properties. A Nyquist (1928) 1 filter in closed form is proved to be ISI-free with or without matched filtering when its complex transfer function is derived from an initially given Nyquist 1 filter. The simplicity of the application of this procedure is illustrated by an example.