Synthesis of Band-Pass Ladder Network

The synthesis of frequency-asymmetrical band-pass filters which do not depend on the reactance-transformation from low-pass filters presents an important problem from the theoretical and practical points of view. In this paper, sufficient conditions are derived for realizing a nondissipative general "band-pass" filter by means of a reactive ladder network which excludes mutual inductance, except for an ideal transformer connected in cascade to one end thereof, and for realizing reactive "band-pass" ladders using a minimum number of inductors (or capacitors). Moreover, the relation between negative values of reactive elements of the filter and its transmission characteristic is investigated. The method of synthesis for these kinds of ladders is presented in detail and some experimental results are included.