High frequency millimetre wave absorbers derived from polymeric nanocomposites

In this paper, an improved dipole-moment model for characterizing near-field coupling and far-field radiation from an IC based on near-field scanning is proposed. An array of electric and magnetic dipole moments is used to reproduce the field distributions in a scanning plane above an IC. These dipole moments can then be used as noise sources for the IC. In order to ensure the accurate prediction of the near-field coupling from the IC, the regularization technique and the truncated singular-value decomposition method are investigated in this paper, together with the conventional least-squares method, to reconstruct the dipole moments from the near-field scanning data. A simple example is used to demonstrate the approach. The improved dipole-moment model is particularly useful for addressing radio-frequency interference issues where near-field noise coupling needs to be accurately analyzed.

https://scholarsmine.mst.edu/cgi/viewcontent.cgi?article=3074&context=doctoral_dissertations

An Improved Dipole-Moment Model Based on Near-Field Scanning for Characterizing Near-Field Coupling and Far-Field Radiation From an IC

Spread spectrum is a technique introduced for mitigating electromagnetic interference (EMI) problems in many class of circuits. In this paper, with particular emphasis on switching DC/DC converters, we consider the most common and most efficient known spreading techniques, looking for spreading parameters that ensure the highest EMI reduction and the lowest performance reduction in the circuit where the spreading is applied. The result is an interesting tradeoff not only between EMI reduction and performance drop, but also on the EMI reduction itself when considering different EMI victim models. The proposed analysis is supported by measurements on two switching DC/DC converters: 1) based on pulse-width modulation and 2) based on the resonant converter class.

EMI Reduction via Spread Spectrum in DC/DC Converters: State of the Art, Optimization, and Tradeoffs

A simple miniature magnetic-field probe for near-field measurements in 9-kHz–20-GHz bandwidth, which is applied to high-speed circuits, has been proposed and manufactured. The magnetic-field probe is built on a four-layer printed circuit board (PCB) using high-performance and low-loss Rogers material ( $\varepsilon _{r}= 3.48$ and tan $\delta = 0.0037$ ). Electric field coupling can be suppressed by PCB shielding structure of the magnetic-field probe. Coax-thru-hole via array technique is used to achieve impedance match. The resonance in working frequency band is suppressed through via fence, making $\vert S_{21}\vert $ rather smooth in the operation band. Experimental results show that the working frequency band is up to 9 kHz–20 GHz.

A Simple Miniature Ultrawideband Magnetic Field Probe Design for Magnetic Near-Field Measurements

This paper presents the models of the coupling between the transverse electromagnetic (TEM) field generated in the TEM cell and the arbitrarily oriented microstrip (MS) lines and coplanar waveguides (CPW). The lines are modeled in the frequency and time domain by taking into account different geometries and two types of subminiature version A connectors. The method of lines is used to calculate the capacitance matrix for the MS and CPW lines inserted in the TEM cell. The capacitance matrix is then used to calculate the inductance matrix, i.e., self- and coupling inductances. A number of simulations are performed in order to obtain the set of capacitance and inductance matrices for various line geometries. These results are fitted by using linear regression models. The closed-form equations for the coupling parameters are derived. The closed-form equations are used for the evaluation of coupling of arbitrarily oriented lines. The coupling models are compared against the measurements and found to be very accurate and can be used for efficient coupling modeling between the MS and CPW lines and TEM cell.

Characterizing the TEM Cell Electric and Magnetic Field Coupling to PCB Transmission Lines

Throughout the decades of continuous advances in semiconductor technology, from the discrete devices of the late 1950s to today's billon-transistor system-on-chip, there have always been concerns about the ability of components to operate safely in an increasingly disruptive electromagnetic environment. This paper provides a nonexhaustive review of the research work conducted in the field of electromagnetic compatibility (EMC) at the IC level over the past 40 years. It also brings together a collection of information and trends in IC technology, in order to build a tentative roadmap for the EMC of ICs until the year 2020, with a focus on measurement methods and modeling approaches.

/pdf/the-electromagnetic-compatibility-of-integrated-circuits-49xkw7fvs2.pdf

J.J. Whalen

Papers

The Electromagnetic Compatibility of Integrated Circuits—Past, Present, and Future