Johan Catrysse

Efficient Reciprocity-Based Algorithm to Predict Worst Case Induced Disturbances on Multiconductor Transmission Lines due to Incoming Plane Waves

In this paper, an efficient reciprocity-based algorithm is proposed to predict the worst case voltages and currents induced by external plane waves at the ports of a multiconductor transmission-line system. The proposed algorithm consists of two main steps. In the first step, the far-field radiation of the multiconductor transmission-line system is fully characterized by a minimal number of full-wave simulations. In the second step, this information is used to efficiently evaluate the voltages and currents induced by a plane wave with arbitrary angles of incidence and polarization. After this, their worst case values can be easily found. The main advantage of the proposed algorithm is that no new full-wave simulations are required if different incoming plane waves or different sets of terminations at the ports of the multiconductor transmission-line system are to be considered.

Measured distortion of the output-waveform of an integrated OPAMP due to substrate noise

In mixed signal applications, interference problems due to ground noise and substrate noise are well known. The problem is becoming very timely in applications, such as the logical control of analog amplifiers in monolithic technologies, because of two reasons: the use of higher clock frequencies and high speed logic circuitry, and the technologies moving into 1 /spl mu/ and submicron regions. In this paper, some measured results are reported on the effects caused by logical control pulses on the behavior of OPAMPs. The results were gained from sophisticated experiments, and can serve as a basis for further theoretical investigations. >

In situ testing of large machines: Alternative methods for conducted emission measurements

On the legal aspect, the new European Directive on ElectroMagnetic Compatibility 2004/108/EC concerns also large machines. On a technical point of view, the special situation to characterise the EMC behaviour of large machines imply that current procedures are complex and very expensive, and in some cases even not possible. Adapted measuring methodologies and procedures are needed. As a response to this situation and within the European R&D Frameworks, the TEMCA2 project aimed to develop new and adapted methodologies for the assessment of EMC related to this type of industrial large machinery.

A new stripline measuring setup for the characterisation of conductive gaskets up to 18 GHz

Due to the impact of higher and higher frequencies, the Shielding Effectiveness (SE) characterisation of shielding gaskets at frequencies above 1 GHz is needed for on board shielding applications. Although the standard IEEE Std 1302™ - 2008 is covering the characterisation of shielding gaskets up to 18 GHz, the methods proposed in this standard are not applicable for these thin and small ‘on board’ gaskets. A method overcoming this problem is proposed in this paper.

Hidden reflection phenomena on inverter-fed induction motors

When supplying an induction motor by a PWM-inverter through long cables, reflections occur. For some inverters other reflection phenomena than the usual overvoltages appear at the motor side, namely steps smaller than 0.5 p.u. of the busvoltage, also called stair stepping. The stair stepping reflection phenomenon occurs at the commutation from IGBT to diode. Stair stepping depends on the magnitude of the current, the cable impedance and on the dead time of the IGBT gate-signal. The reflection phenomenon increases the turn on time of the diode

Correlating the High-Frequency Shielding Performance of 'On-Board' Gaskets when Characterized using a Stripline or Reverberation Room Method

This paper compares the shielding performance or shielding effectiveness of gaskets for on-board applications when determined with either a stripline method or a reverberation room method. The shielding performance is considered in the frequency range from 1 up to 40 Ghz. Similar to PCB-level enclosures, gaskets for on-board applications differ significantly from other shielding products, therefore requiring an appropriate definition for their shielding effectiveness. It is shown by full-wave simulations that a 3rd order polynomial fit of the shielding effectiveness obtained with the stripline method correlates well with the shielding effectiveness obtained with a reverberation room method, in which case the shielding effectiveness is defined as the ratio between the radiated/received power with and without gasket.

Equivalent circuit model of the TEM cell electric and magnetic field coupling to microstrip lines

Electromagnetic compatibility (EMC) analysis of high-speed circuits is becoming mandatory due to the rapid increase in operating frequencies, RF interference and layout densities. Radiated susceptibility tests are important part of overall EMC analysis. In this paper the focus of investigation is on models of the coupling between a transverse electromagnetic (TEM) field generated by the TEM cell and the microstrip lines. In order to accurately model the coupling the models for microstrip lines, SMA connectors and TEM cell are developed. The coupling models are provided for transversal and longitudinal microstrip lines. The results for coupling capacitances are compared against results obtained by Method of Lines (MoL). The presented models are very accurate and include only passive elements, and therefore can be used for efficient coupling modelling between microstrip lines and the TEM cell septum.

Scalable Equivalent Circuit Modelling of the EM Field Coupling to Microstrips in the TEM Cell

A scalable circuit model of the electric and magnetic field coupling to microstrips placed on the top wall of a TEM cell is presented. The coupling parameters have been derived using approximating equations to reduce simulation times as much as possible. Simulation results of the resulting circuit model are validated by S-parameter measurements.

Measured crosstalk on chips using specially designed components

In mixed signal applications, interference problems due to crosstalk are well known. These problems have also been reported at the VLSI-IC level. A specially designed chip was used for performing crosstalk measurements at the chip level. Some of the observed effects are reported. The results were gained from sophisticated experiments and can serve as a basis for further theoretical investigations. >

Towards a stripline setup to characterise the effects of corrosion and ageing on the shielding effectiveness of EMI gaskets

This paper introduces a novel measurement set-up dedicated to the characterization of the evolution of the high-frequency shielding-effectiveness of gaskets due to corrosion and ageing. The measurement set-up is based on the recently introduced stripline set-up which has been validated previously up to 40 GHz. Compared to the original stripline set-up, the adapted set-up has a removable “clamping module” which can be easily mounted and removed from the set-up. The clamping module allows to age the gasket inside e.g. a climate chamber while always keeping the gasket under the same compression rate. As the clamping module can be made out of different materials, it allows to study the influence of shielding-effectiveness of gaskets when applied to different materials. In order to avoid parallel leakage inside the measurement set-up, a high-performant gasket needs to be compressed below the module. Based on full-wave simulations, it is shown that the shielding-effectiveness given by this gasket underneath the clamping module is the main determining factor for the dynamic range of the set-up. In addition, a first set of measurements show the validity of the measurement set-up and approach.