A Novel Implementation of the Perturbation Technique for Better Integration of NUTLs with Periodic Geometry

In this work, a novel implementation of the perturbative technique (PT) recently proposed in [1] for the solution of nonuniform transmission-lines (NUTLs) is presented. Unlike the original PT, the proposed method provides a 2n-port S- parameter representation of the NUTL under analysis, which can be afterwards used in combination with different terminal conditions and/or cascaded with other 2n-port networks. As an application example, an interdigital tabbed microstrip line terminated in SMA connectors and involving a bend discontinuity is solved by the proposed technique. The obtained predictions are validated versus those provided by a full-wave solver.