Antenna Modeling Based on a Multiple Spherical Wave Expansion Method: Application to an Antenna Array

WOSInternational audienceA method to derive an equivalent radiation source for planar antennas is presented. This method is based on spherical near-field (NF) data (measured or computed) to ascertain an equivalent set of infinitesimal dipoles placed over the main antenna aperture. These produce the same antenna radiation field, both inside and outside the minimum sphere enclosing the antenna. A spherical wave expansion (SWE) of the NF data is written in terms of infinitesimal dipoles using a transition matrix. This matrix expresses the linear relations between the transmission coefficients of the antenna and the transmission coefficients of each dipole. The antenna a priori information are used to set the spatial distribution of the equivalent dipoles. The translational and rotational addition theorems are exploited to derive the transmission coefficients of the dipoles. Once the excitation of each dipole is known, the field at any aspect angle and distance from the antenna is rapidly calculated. Computations with EM simulation data of an antenna array illustrate the reliability of the method

The use of infinitesimal dipoles and the spherical wave expansion for planar antennas modeling

International audienceIn this paper, a method to derive an equivalent radiation model for planar antennas is presented. This method uses the spherical near-field (NF) data (measured or computed) to ascertain an equivalent set of infinitesimal dipoles placed over the main antenna surface. The spherical wave expansion (SWE) of the NF data is written in terms of infinitesimal dipoles using a transition matrix. This matrix expresses the linear relations between the spherical wave coefficients of the antenna and the spherical wave coefficients of each dipole. Once the excitation of each dipole is known, the field at any angle and distance from the antenna is rapidly calculated even inside the minimum sphere. Computations with EM simulation data of an antenna array illustrate the reliability of the method

Kron Simulation of Field-to-line Coupling Using a Meshed and a Modified Taylor Cell

International audiencePrinted Circuit Board (PCB) traces play a role in the immunity of electronic products. Contrary to Integrated Circuits (ICs), the layout of PCB traces can be changed rather late in a product's design. Therefore, it is interesting to equip the PCB designer with simple tools that predict the immunity of his PCB traces. In this article, we compare two simulations of field-to-long line coupling based on Taylor's model. Firstly, the line is meshed into electrically short Taylor cells and numerically simulated using Kron's method. Secondly, we use one modified Taylor cell, which does not need meshing and is a closed-form, analytical result. The two simulations turn out to be equally precise on a straight microstrip line, the meshed simulation being more flexible, the simulation using a modified Taylor cell being faster

The conducted immunity of SPI EEPROM memories

International audienceThis paper focus on the conducted immunity measurement of non-volatile memories up to 1 GHz. A specific measurement flow is introduced, which makes possible to compare the EMC performances in different test cases. Trough measurements and simulation, this study gives a real view on the immunity difference of this integrated circuits (IC)

Assessment of the Immunity of Unshielded Multicore Integrated Circuits to Near Field Injection

International audienceThis paper presents a comparative assessment of the electromagnetic immunity of 4 integrated logic cores to near-field injection. These cores, located on the same die, are identical from a functional point of view, but differ by their design strategies. The injection is performed above each core according to the 6 components of the electromagnetic field, using appropriate probes. These results demonstrate that the die and bondwires of an integrated circuit can be sensitive to both magnetic and electric fields, and that some design rules can improve the immunity of integrated circuits to near-field interference

Design of a 20 GHz DPI method for SOIC8

The direct power injection (DPI) test defined in IEC 62132-4 measures the conducted immunity of integrated circuits (ICs) up to 1 GHz. As the frequency of functional and interference signals is increasing, we would like to characterise immunity for higher frequencies as well. In this paper, we show why typical IEC 62132-4 compliant DPI set-ups become inaccurate when going up to 20 GHz. We propose to determine the power Ptrans actually transmitted to the device under test (DUT) by using offline short-open-load-thru (SOLT) or thru-reflect-line (TRL) calibration. Furthermore, we design a low-cost FR4 printed circuit board (PCB) that allows for testing of SOIC8-packaged ICs. We verify that this board has acceptable and reproducible losses up to 20 GHz, as well as acceptable crosstalk.Peer ReviewedPreprin

Design of a 20 GHz DPI method for SOIC8

International audienceThe direct power injection (DPI) test defined in IEC 62132-4 measures the conducted immunity of integrated circuits (ICs) up to 1GHz. As the frequency of functional and interference signals is increasing, we would like to characterise immunity for higher frequencies as well. In this paper, we show why typical IEC 62132-4 compliant DPI set-ups become inaccurate when going up to 20GHz. We propose to determine the power Ptrans actually transmitted to the device under test (DUT) by using offline short-open-load-thru (SOLT) or thru-reflect-line (TRL) calibration. Furthermore, we design a low-cost FR4 printed circuit board (PCB) that allows for testing of SOIC8-packaged ICs. We verify that this board has acceptable and reproducible losses up to 20 GHz, as well as acceptable crosstalk

Over 40W, X-Band GaN on SiC MMIC amplifier

In this paper we present the study and obtained results of a MMIC High Power Amplifier operating in X-band. The device is designed using 250nm GaN HEMT on SiC process. The targeted specifications include pulsed operation from 8 to 10.5GHz. In pulsed mode and 28V of drain voltage, an output power more than 40W with (37-40)% PAE has been achieved throughout the bandwidth, while remarkable 52.4W output power with associated 37% PAE has been recorded at 8.75GHz for a 32V of drain voltage. The HPA stability has been studied by considering the influence of external decoupling components and dedicated testing environment

Techniques de caracterisation en champ proche, applications aux antennes et aux circuits

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