Page 165 - DSP Integrated Circuits

150 Chapter 4 Digital Filters

4.16 DESIGN OF WAVE DIGITAL FILTERS

The basic relationships among the wave digital filter, the corresponding reference
filter, i.e., the transmission line filter, and the lumped element filter are summa-
rized in Figure 4.39.

Figure 4.39 Relationships among the wave digital filter, transmission line filter, the IP-
domain filter, and the lumped element filter

The purpose of the lumped element filter is to simplify the design process by
allowing the use of conventional lumped element filter theory and design tools. In
principle, all commensurate-length transmission line networks can be used as ref-
erence filters for wave digital filters. Furthermore, wave digital filters represent-
ing classical filter structures are also viable since all lumped element networks