A.S. Bondarenko, B.M. Kats, V.P. Meschanov
A new structure of the phase-shift element of the phase-shifter on microstrip transmission lines is investigated. The structure is based on a microstrip coupled transmission line section, two ports of which are interconnected by means of an additional matching element being a single microstrip transmission line section. In the result of numerical modeling, the possibility of broadband matching of the ports as well as adjusting of a phase-versus-frequency characteristic by setting optimum values of the parameters of coupled microstrip transmission lines and matching element is shown. Examples of realizations of microstrip fixed phase shifters with operating frequency range up to one octave and return losses not less than -30 dB are given. The main advantages of a new structure are a wide range of realizable nominal phase shifts, the possibility of modeling in the frames of the circuit theory, and the simple and planar topology.