Reactively-Loaded EBG Transmission Lines with Periodicity Truncation for Improvement of the Stop Band Performance

This paper deals with reactively-loaded artificial transmission lines of interest for device miniaturization and for harmonic suppression. However, contrarily to most reactively loaded lines, based on periodic structures, periodicity in the reported lines is truncated in order to enhance the degrees of freedom, thereby improving their stop band performance. Two approaches are considered: (i) lines with unit cells of identical electrical length, characteristic impedance and slow wave ratio, but loaded with different reactances (step impedance shunt stubs); (ii) lines with unit cells of different electrical length. The achievable effects of both approaches are discussed in the paper, and validated on the basis of the reported circuit schematics. The second approach is applied to a power splitter with compact size and filtering capability.