Modeling electromagnetic wave coupling and mode conversion effects in multitwisted bundle of twisted‐wire pairs (MTB‐TWP) above ground plane

A multiconductor transmission line (MTL) model is developed for predicting electromagnetic wave coupling effects with multitwisted bundle of twisted‐wire pairs (MTB‐TWP) running above a ground plane. Such MTB‐TWP is described as a sequential repeated structure, where all its parameters are formulated in terms of sequences. In particular, the parametric equations of all the wires are derived and described by a set of generalized equations, where the unit tangent vector for each wire is also determined analytically. In addition, the averaged per‐unit‐length (p.u.l.) parameters are described by recurrence formulas. Further, the equivalent voltages for describing the field‐to‐wire coupling of MTB‐TWP are obtained and determined analytically. The modal domain decomposition is performed with special loading terminals to split out the common mode (CM) and differential mode (DM) signals, where the CM‐to‐DM conversions are further investigated in order to indicate the balanced property in such MTB‐TWP system. On the other hand, the effect of dielectric coatings of all the wires is also characterized, where the averaged modal p.u.l. capacitance matrix is obtained numerically. A comparison is performed with the other wiring structures to visualize the benefits of our MTB‐TWP model. An extended MTL model is also validated in comparison with the commercial software FEKO.