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It is well known that wideband electromagnetic noise is caused by ESD (electro-static discharge) events. Especially, the micro gap ESD of less than 1 kV produces the impulsive electromagnetic noise up to GHz bandwidth. The ESD noise is menace to cause malfunction of high-tech electrical equipment and systems. Then, the impulsive electromagnetic noise caused by the ESD was examined to clear the radiation...
The errors, due to stair-cased meshing, in the Shielding Effectiveness (SE) of cavities modelled with thin boundaries, in the Finite-Difference Time-Domain (FDTD) method, are examined. The errors in SE are found to be associated with the error in the surface area of the cavity caused by the use of a stair-cased mesh. An empirical solution is demonstrated, which improves the stair-cased model accuracy...
Electromagnetic shielding is of high importance to avoid coupling between cables or pick-up of external fields. The use of metal braids around cables improves its protection. Shielding effectiveness of these braids is characterized by the transfer impedance of infinitesimally short braids. In practice, the transfer impedance is measured along a braid of finite length by either a line injection or...
This paper focuses on power amplifiers linearization based on adaptive predistortion and their susceptibility to IEMI. The method gives very good results in simulation and on a test bench. The idea here is to illuminate the power amplifier with an intentional electromagnetic interference while its model coefficients are being processed. This leads to an erroneous model inference and therefore a poor...
Knowledge of the shielding effectiveness of an enclosure is important for the electromagnetic compatibility of electronic systems. The shielding effectiveness of an enclosure depends on the absorption cross section of its contents. It might be expected that the energy absorption in an electronic circuit changes according to the operating state of the semiconductor devices which compose the active...
The paper presents a detailed analysis and experimental results of the radiated power measurement in line with two over-the-air methods. The results indicated that the first method, which is based on the field strength measurement when changing the receiving antenna height, worked very well in DVB-T broadcast band. In FM broadcast band the use of this method becomes more difficult with the increase...
Flexible printed circuits (FPCs) are already widely used to connect printed circuit boards in compact systems such as smartphones, tablets and laptops, where weight and space are at a premium. The latter are also increasingly important issues in the automotive industry, suggesting that flexible printed interconnects could also offer advantages in vehicle applications. This paper therefore discusses...
The concept of ultrathin switchable microwave filter consisting of graphene sheet and slot array is presented. The proposed microwave filter shows a passband ranging from 14.4 GHz to 15.6 GHz, in which the transmission can be electrically controlled and decreased to lower than −17.5 dB at resonance achieving an off state, via electrostatic gating on the graphene stack. The analysis of transmission...
This study originates from IEC 61967-4 standards for measuring electromagnetic emissions at the chip level. The measuring probe with fixed SMA connector in IEC 61967-4 method was improved with a proposed radio frequency (RF) current probe by featuring a semi-rigid coaxial cable to be capable of making movable measurements, and thus enhancing the flexible probing usage. To evaluate and validate the...
Power electronic components such as busbars, capacitors, and inductors are positioned close to each other when designing a high power density converter. Therefore, the internal near field couplings between these components should be considered when designing a low electromagnetic interference (EMI) converter. In this paper, we propose a new frequency domain model for simulation of EMI in power electronic...
Near electromagnetic fields radiated by a Library RFID system has been characterized and studied in this work. An RFID reader loop antenna operating at 13.56 MHz was designed. The radiated magnetic field above the fabricated circuit was measured using a 3D H-field probe especially designed for near-field measurements. The obtained levels were checked in terms of satisfaction of the European Directives...
A worst-case model of spurious resonances which can occur in electromagnetic system consisting of an antenna, cable and transmitter output filter (or receiver input filter) is proposed. These resonances may cause significant increase in power of spurious emissions for transmitting equipment and the decrease in out-of-band radiated susceptibility levels for receiving equipment. Three amplitude-frequency...
This paper presents the results of a test campaign meant to determine coupling paths into a laboratory test setup of typical power grid substation SCADA (Supervisory Control and Data Acquisition) electronics. The devices were tested against conducted threats in a bulk current injection (BCI) setup and radiated threats inside a transverse electromagnetic (TEM) waveguide as well as with a near-field...
Modern electronic systems with a high degree of interconnectivity are prone to intentional and unintentional electromagnetic interference (IEMI/EMI). Therefore, emission and immunity measurements of all parts of a system are essential in order to prevent system failures or even breakdowns. Some of these IEMI measurements, especially the high-altitude electromagnetic pulse (HEMP) immunity tests are...
Due to the powertrain electrification in electric- and hybrid vehicles enormous challenges arise considering the electromagnetic compatibility (EMC) of the vehicles. The power electronic components used produce high broadband interferences possibly affecting vehicle components located in the 12V system. In order to meet these challenges the traction system is built up thoroughly shielded and isolated...
An effective technique for reducing electromagnetic interference within enclosures hosting microwave circuits is based on an artificial Perfect Magnetic Conductor (PMC) surface. This fictitious surface can be obtained by accordingly placing metallic pins on a regular pattern covering the enclosure lid. Previously published papers developed simple analytical expressions to predict the band-gap limits...
In this paper, an ultra-thin polarization-independent wideband metamaterial absorber (MA) is proposed. The unit cell of this MA is composed by a branch-like pattern with four patch-resistors, FR4 substrate and metallic plate, which can delicately combine dielectric loss and ohmic loss. The electromagnetic performances of the MA are studied by full-wave simulations based on finite-element method. The...
For the analysis of power transmission line, under steady state, the evaluation of the longitudinal profile of voltage and current allows predicting the existence of overvoltage or overcurrent even when the voltage at both ends may have acceptable values. For doing so, computer modelling of transmission line has been so far the most obvious and feasible way. However, today, this evaluation has become...
The shielding performance of a metallic building located close to a telecommunication tower hit by lightning is investigated. Two models of lightning strike are adopted for the shielding analysis. The first model includes the current distribution along the lightning channel while the second model is a surge current injected into the top of tower only. For each model the performance is evaluated both...
Scattering objects like wind turbines or buildings have a significant influence on radar signal propagation. In order to predict the appropriate impact of construction or modification of a building a simulation of the scenario is often helpful. Using traditional full wave simulation methods this leads to an unacceptable high amount of simulation effort due to the geometrical very large structures...
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