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The paper presents comparative analysis of the properties of impedance stepped transformers both with monotonous and nonmonotonous step-to-step impedance variation. A miniature stepped transformer of a new structure based on a cascade of an even number of uniform transmission line sections has been synthesized. Section lengths are considerably shorter than a quarter of the central wavelength, and the section impedances alternate. The proposed transformers are the simplest to implement among the available analogs. As an example, the results of the solution of the Chebyshev approximation problem for the four- and six-section transformers of different specifications are given.

A new structure for TEM transmission line ultrawide-band differential phase shifters is proposed. This consists of a cascade of two-ports, each of which is a single coupled section with parallel transmission lines connected to each other at one end. The section lengths and coupling coefficients are different. The results of numerical synthesis have been tabulated for phase shifters of 90 degrees differential phase shift. The proposed structure has the advantage of a lower coupling coefficient and improved phase-frequency characteristic in comparison with the other stepped phase shifters.