Network Theory, Filters, and Equalizers

In Part I the fundamental properties of networks are reviewed with particular emphasis on two and four-terminal networks. The use of reactive networks for impedance matching is covered. Fundamental network definitions and network theorems are reviewed. The general mesh equations of the network are given, together with their solution for input and transfer impedance. Properties of two-terminal reactive networks are presented in terms of zeros and poles from the viewpoint of Foster´s reactance theorem. Methods of synthesizing any impedance realizable by a two-terminal reactive network are given. Reciprocal impedances are discussed, and the methods of deriving a reciprocal network given. The general properties of four-terminal networks are reviewed in terms of image impedance and image transfer constant. The alternate presentation on terms of iterative impedance and iterative transfer constant is also covered briefly. The subjects of impedance matching and insertion loss are considered and formulas are presented for the mismatching factor and for insertion loss. Properties of four-terminal networks based upon T, π, L, and lattice sections are summarized. The use of reactive T, π, and L networks for impedance matching is reviewed, and charts are presented for designing a matching network to meet any given requirements.