Simple, Taylor-Based Worst-Case Model for Field-to-Line Coupling

Abstract

Abstract-To obtain Electromagnetic Compatibility (EMC), we would like to study the worst-case electromagnetic field-induced voltages at the ends of Printed Circuit Board (PCB) traces. With increasing frequencies, modelling these traces as electrically short no longer suffices. Accurate long line models exist, but are too complicated to easily induce the worst case. Therefore, we need a simple analytical model. In this article, we predict the terminal voltages of an electrically long, two-wire transmission line with characteristic loads in vacuum, excited by a linearly polarised plane wave. The model consists of a short line model (one Taylor cell) with an intuitive correction factor for long line effects: the modified Taylor cell. We then adapt the model to the case of a PCB trace above a ground plane, illuminated by a grazing, vertically polarised wave. For this case, we prove that end-fire illumination constitutes the worst case. We derive the worst-case envelope and try to falsify it by measurement in a Gigahertz Transverse Electromagnetic (GTEM) cell.

Using a Modified Taylor Cell to Validate Simulation and Measurement of Field-to-Shorted-Trace Coupling

“…As anything can be modeled in a full-wave solver, only the validity constraints of modified Taylor cells need to be considered. The modified Taylor cell predicts the coupling of a grazing, horizontally polarized plane wave to one straight, characteristic microstrip segment [5]. If the impedance discontinuities between segments are negligible, a finite cascade of microstrip segments of different planar orientation can be modeled by cascading Taylor cells [6].…”

“…Given the available surface, a threesegment microstrip is chosen for simplicity's sake. Because the far end has the stronger high-frequency coupling for a straight microstrip [5], the far-end induced voltage is studied. At the near end, a short calibration standard is connected, inevitably including an electrical delay ⌧ d .…”

“…Recently, a simple model was developed by the authors for a grazing, horizontally polarized incidence on a trace with matched terminal impedances: the modified Taylor cell [5], [6], which has a closed-form solution.…”

Control of a Mos Inverter by Out-of-Band Pulsed Microwave Excitation

“…The effective PME is the result of HPM coupling onto printed circuit board (PCB) traces (back door coupling) [13]. It is observed that a MOS inverter that initially follows the interference may switch to a state where it is totally inhibited and pinned down to the lower logic level.…”

Taking Into Account GTEM Field Nonuniformities in Radiated Immunity Simulations Through a Simple Measurement

“…In previous research, Op 't Land et al proposed a model for the coupling of a plane wave to a PCB (Printed Circuit Board) trace [1]. To challenge the model, they confronted it to measurements where the GTEM cell was used to emulate the plane wave.…”