ABSTRACT
This chapter deals with the design of optimally realizable data transmission filters. A passive realization has been shown, and the filter performance displayed in both frequency and time domains. The frequency domain responses (especially the group delay) are somewhat at variance with accepted design practice for data transmission filters. A primary requirement of the realizable filter is to provide near zero isi when subjected to a synchronous stream of input impulses, with each impulse carrying a bit of data information. Passive lossless filters are more difficult to design, because of the complex transmission zeros. The filters described next are realizable and closely approach the Nyquist ideal filter. The result of the design is a set of poles and zeros for the transfer function of a composite filter. As the filters are self-equalized, no separate group delay equalizer is required. The filter design has its data transmission performance placed at a global minimum.
