SHORT-STEP-STUB CHEBYSHEV IMPEDANCE TRANSFORMERS.
A general procedure is presented for the synthesis of short-step impedance transforming filters consisting of short cascaded TEM transmission-line sections and at least one commensurate length open-circuit stub. One member of the short-step family in particular is very compact and relatively easy to implement. Simple expressions for evaluating the passband performance of impedance transformers are derived, and element values are given for a selection of compact octave-bandwidth transformers. The relationship between short-step transformers and lumped-element impedance matching networks is pointed out, leading to an exact procedure for the semilumped implementation of lumped-element transformers.