Synthesis of microstrip multiconductor lines, operating in normal mode

Abstract

Microstrip multiconductor lines (MMCL) are broadly used in microwave areas as transmission lines, or as physical models for developing various devices: couplers, filters etc. In general case, separate waves propagate along every conductor, and interference takes place in N-conductor MMCL. Transmitted signals are not distorted if structure of propagating wave remains unchanged, i.e. normal mode wave propagates; therefore it is necessary to restrict wave propagation to normal mode in MMCL, in order to minimize signal distortion. Synthesis technique of four-conductor symmetrically coupled MMCL, operating in normal mode, is presented in this article.