Circuit-Concept Approach to Externally Excited Transmission Lines

Efficient Modeling of Transmission Lines With Electromagnetic Wave Coupling by Using the Finite Difference Quadrature Method

“…Under such a condition, the principal propagation mode of the TLs is TEM, and can be accurately described by the Telegrapher's equations. Theoretical analysis and experimental results have shown that the external EM wave illuminating can be modeled as forcing terms which are added in the Telegrapher's equations [1], [12]- [15]. Let the illuminating EM wave be represented in the Cartesian coordinate system by (1) and the TLs stretch along the direction.…”

“…The -domain representation of the wave is (9) where is the waveform of the field and is the unit vector representing the polarization of the electric field in the Cartesian coordinate system is the position vector is the wave vector. The components of along the -, -, and -axes are (10) The components of the phase in the Cartesian coordinate system are (11) With the previous definitions, (9) becomes (12) In the time-domain, the wave in (9) is represented by (13) where the wave components along the axes are denoted by (14) C. Equivalent Sources to TL With Reference Line By using the previous definitions, the transverse field contributions in (6) for the th conductor are derived as (15) and the longitudinal field contributions in (7) for the th conductor are (16) where Substituting (15) and (16) into (4) and (5) (17) and (18) as (19) (20) For the quasi-TEM assumption under which the dimensions of TLs cross-sectional sizes are much smaller than the longitudinal sizes, i.e., , we take the first two items of the following series expansion of :…”

Simple transmission line model suitable for the electromagnetic pulse coupling analysis of twisted-wire pairs above ground

“…In order to predict these coupling effects, a general procedure is to i) determine the distributed sources (generated by inductive or capacitive coupling) induced on a TL [2], ii) develop an equivalent TL model [3,4,5,6,7,8], and then iii) carry out the coupling analysis for each model. Especially, it is critical to develop an equivalent TL model to accurately represent the structural characteristics of the TL.…”

“…Basically, the TWP-TL is more suitable than a single-wire pair (SWP) TL because the former can cancel out the EMP coupling from external EM field [3,4]. Among previous TL models for the TWP-TL, a rectangular loop model [3,4,5] and a bifilar helix model [6,7,8] were employed. However, the former may lead to inaccurate results because it is too much simplified.…”

Field coupling to nonuniform coupled microstrip transmission lines

“…Some of these authors consider the structure of a single transmission line in an inhomogeneous medium [9 -12]. The problem of a single nonuniform transmission line is solved in [5] using the principles introduced in [3]. This article is the first to solve the effect of the external EM wave on a coupled structure of nonuniform microstrip (nonhomogeneous) transmission lines using a combined fullwave and quasi-transverse EM (TEM) approach.…”