Analysis of Orbital Angular Momentum (OAM) Antennas in Complex Environments

Electromagnetic waves can have a form of moment called the Orbital Angular Momentum (OAM). In waves with this property, the area perpendicular to the direction of propagation does not have a constant phase, as is the case with plane waves. Rather, the phase varies around the center of the wave and this phase distribution rotates in the direction of propagation. From the possible phase distributions and the direction of rotation different orthogonal modes result. This means that the modes do not influence each other and can therefore be used well for communication purposes.

In the past some properties of communication with OAM antennas have been investigated. The properties of OAM antennas shall now be further analyzed from the point of view of EMC.

Dipolar array of eight elements with which the first OAM mode is excited by operating the individual dipoles with a phase difference of ∆Φ=45°. The operating frequency is f=100 MHz. Source: TET, TUHH

Phase of the z-component of the E-field on the surface perpendicular to the direction of propagation. The phase was evaluated in three different distances to the antenna. As antenna a dipole array of eight elements was used, which excites the first OAM mode. The circular sections show how the phase rotates exactly 360° in the azimuthal direction. You can also see how this phase distribution rotates in the direction of propagation. Source: TET, TUHH

Funding: Free and Hanseatic City of Hamburg
Contact: Michael Wulff, M Sc.
Start date: 01.12.2019

EMC of Complex Systems

Ph. D. Thesis Fabian Happ. 01.04.2012 – 01.09.2017

In this thesis a numerical method based on the Method of Moments and analytical formulations are developed to calculate electromagnetic fields in the vicinity of Carbon Fiber Composite (CFC) materials. The methods are applied to predict the shielding effectiveness of different CFC materials, to calculate lightning transfer functions for the coupling into an aircraft geometry made of CFC, and to estimate the influence of CFC on the crosstalk between transmission lines.

Apertures in a Computer casing (Source: TET, TUHH).

Current distribution on a field illuminated Computer casing (Source: TET, TUHH).

Related Publications:

Fabian Happ, Heinz-Dietrich Brüns, Frank Gronwald

An efficient implementation of the periodic method of moments for shielding effectiveness calculations of thin-wire grids Inproceedings

2nd URSI AT-RASC, Gran Canaria, Spain, May 28 – June 1, 2018.

Links

Fabian Happ, Heinz-Dietrich Brüns, Frank Gronwald

Application of Huygens‘ Principle for the Fast Calculation of Field Penetration Through Aperture Arrays Journal Article

IEEE Transactions on Electromagnetic Compatibility, 6 , 2018.

Links

Fabian Happ

Method of Moment Analysis of Layered Carbon Fiber Composites with Applications to Electromagnetic Compatibility PhD Thesis

2017, ISBN: 978-38440-5630-3.

Fabian Happ, Arne Schröder, Gazmend Mavraj, Heinz-Dietrich Brüns, Frank Gronwald

Numerical Shielding Analysis of Anisotropic Multilayer Materials by the Method of Moments Journal Article

IEEE Transactions on Electromagnetic Compatibility, 1 , 2017.

Links

Jesper H.G.J, Lansink Rotgerink, Fabian Happ, Jan-Joris van Es

Crosstalk between wire pairs above a composite ground plane Inproceedings

2016 International Symposium on Electromagnetic Compatibility - EMC EUROPE Wroclaw, Poland, 2016.

Links

Fabian Happ, Gazmend Mavraj, Heinz-Dietrich Brüns, Frank Gronwald

On the Choice of Huygens’ Surfaces in the Vicinity of Electrically Small Apertures Inproceedings

EMC Europe, Wroclaw, Poland, September 5 – 9, 2016.

Links

Fabian Happ, Heinz-Dietrich Brüns, Gazmend Mavraj, Frank Gronwald

Numerical Computation of Lightning Transfer Functions for Layered, Anisotropically Conducting Shielding Structures by the Method of Moments Journal Article

Advances in Radio Science, 2016.

Fabian Happ, Frank Gronwald, Heinz-Dietrich Brüns

An Extension of Schelkunoff’s Shielding Theory to Anisotropic Conducting Multilayer Materials Inproceedings

2015 IEEE International Symposium on Electromagnetic Compatibility (EMC), Dresden, Germany, August 16-22, 2015.

Links

Fabian Happ, Heinz-Dietrich Brüns, Frank Gronwald

Benchmark Calculations of Magnetic Shielding at Low Frequencies Inproceedings

IEEE International Symposium on Electromagnetic Compatibility, EMC Europe, Gothenburg, Sweden,September 1-4, 2014.

Links

Fabian Happ, Heinz-Dietrich Brüns, Frank Gronwald

Numerische Simulation der Schirmwirkung von mehrlagigen, anisotrop leitfähigen Materialien Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf), Düsseldorf, Germany, March 11-13, 2014.

Frank Gronwald, Fabian Happ

Methoden der Netzwerkmodellierung von Transferfunktionen indirekter Blitzeffekte auf Grundlage numerischer Simulation in Zeit- und Frequenzbereich Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) , Düsseldorf, Germany, March 11-13, 2014.

Frank Gronwald, Fabian Happ

Adaptive Macromodelling of Lightning Transfer Funcion from Numerical Calculations in Time and Frequency Domain Inproceedings

International Conference on Electromagnetics in Advanced Applications Torino, Italy, September 9-13, 2013.

Links

Fabian Happ, Arne Schröder, Heinz-Dietrich Brüns, Frank Gronwald

A Method for the Calculation of Electromagnetic Fields in the Presence of Thin Anisotropic Conductive Layers using the Method of Moments Inproceedings

EMC Europe 2013, Brugge, Belgium, September 2-6, 2013.

Sebastian Müller, Fabian Happ, Xiaomin Duan, Renato Rimolo-Donadio, Heinz-Dietrich Brüns, Christian Schuster

Complete Modeling of Large Via Constellations in Multilayer Printed Circuit Boards Journal Article

IEEE Transactions on Components, Packaging and Manufacturing Technology, 3 (3), 2013.

HIRF Protection Using Energy Selective Diode Arrays

Cheng Yang, M. Sc., (China Scholarship Council (CSC)), 01.04.2015 – 17.10.2016

With more and more electromagnetic energy being transmitted by radar, radio, TV, mobile, hotspot (Wi-Fi), satellite, and other transmitters, detrimental effects of electromagnetic waves on the environment, e.g. disturbance or even damage of electronic equipment, become more and more a concern. To ensure safe operation of various electronic systems in transmitting or receiving states, electromagnetic protection should be considered especially against high intensity radiation fields (HIRFs). This project focuses on diode arrays for implementation of self-activated and energy selective blocking of electromagnetic wave.

Based on the nonlinear behavior of diodes, diode arrays can be shown to be transparent with respect to small field amplitudes and opaque to large field amplitudes. In theory, we expect the structure to work like a spatial switch, while in practice its protection performance is limited by several factors, such as the response time and operating frequency range of the diodes, the transmission loss of the protective structure and near field coupling effects. Therefore, accurate full wave simulation are being used for evaluation of the electromagnetic performance of protective diode arrays. Up to now, mostly infinitely periodic diode arrays have been studied. Next steps include the simulation of finite and non-periodic diode arrays using the electromagnetic field simulator CONCEPT-II.

Geometrical model of diode array designed for vertical polarized protection against HIRF. The diode array consists of conductive strips and miniature diodes on a low dielectric loss substrate of thickness 0.8mm. The horizontal and vertical distance of adjacent diodes is 3.5 mm and 2.25, respectively (figure adapted from “A Novel Method of Energy Selective Surface for Adaptive HPM/EMP Protection,” IEEE APWL, vol. 12, pp. 112–115, 2013.)

Evaluation model of diode array in CONCEPT-II. The array was placed in the front window of a PEC box, and a receiving antenna is positioned inside the PEC box (side length approx. 50 cm). What can be seen are the surface currents on the PEC box (red color indicates high current amplitudes).

Related Publications:

Cheng Yang, Peiguo Liu, Heinz-Dietrich Brüns, Christian Schuster

Design Aspects for HIRF Protection of a Rectangular Metallic Cavity Using Energy Selective Diode Grids Inproceedings

IEEE Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC), Shenzhen, China, May 18-21, 2016.

Links

Cheng Yang, Heinz-Dietrich Brüns, Peiguo Liu, Christian Schuster

Impulse Response Optimization of Band-Limited Frequency Data for Hybrid Field-Circuit Simulation of Large-Scale Energy-Selective Diode Grids Journal Article

IEEE Transaction on Electromagnetic Compatibility, 58 (4), 2016.

Links

Cheng Yang, Heinz-Dietrich Brüns, Peiguo Liu, Christian Schuster

Validation of a Flexible Causality Treatment for Transient Analysis of Nonlinearly Loaded Structures Inproceedings

2015 IEEE International Symposium on Electromagnetic Compatibility (EMC), Dresden, Germany, August 16-22, 2015.

Analysis of Electromagnetic Interference in Server Casings

Ph.D. Thesis Alexander Vogt. 01.04.2011 – 08.04.2016

With increasing data rates EM emission has become a major issue for EMC and EMI considerations in current server designs. Major sources of EM emission inside include ICs, cables and connectors, and Printed Circuit Boards. While efficient techniques exist to model the interior coupling of PCB cavities (Zpp ), the external (3D) coupling still has to be computed using full-wave techniques.

This project aims to combine the different methods to model and simulate the components of the server. The dimensions and high data rates in addition to the high complexity of the individual components encountered in modern servers lead to a number of unknowns that are commonly in the range of several million. Therefore, efficient numerical methods and approximate models have to be developed.

Modeling the 3D coupling of PCBs using PEC surfaces and dielectric bodies for computation with the Method of Moments (Concept-II)  (Source: TET, TUHH).

Sources of EM emission and related structures inside a server housing (Source: TET, TUHH).

Related Publications:

Alexander Vogt

Analysis of Electromagnetic Interference in Server Casings PhD Thesis

2016, ISBN: 978-3-8440-4660-1.

Alexander Vogt, Torsten Reuschel, Heinz-Dietrich Brüns, Sabine Le Borne, Christian Schuster

On the Treatment of Arbitrary Boundary Conditions Using a Fast Direct H-Matrix Solver in MoM Journal Article

IEEE Transactions on Antennas and Propagation, 64 (8), 2016.

Links

Alexander Vogt, Heinz-Dietrich Brüns, Christian Schuster

Auswirkung absorbierender Materialien auf die Verkopplung von Komponenten innerhalb eines PC-Gehäuses Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) Düsseldorf, Germany, February 23-25, 2016.

Alexander Vogt, Heinz-Dietrich Brüns, Qi Wu, Frank Gronwald, Christian Schuster

A Measurement Setup for Quantification of Electromagnetic Interference in Metallic Casings Journal Article

IEEE Transactions on Electromagnetic Compatibility, 57 (6), 2015.

Links

Qi Wu, Alexander Vogt, Jan Birger Preibisch, Andreas Hardock, Heinz-Dietrich Brüns, Christian Schuster

Modeling of Mutual Coupling between Coaxial Probes in Flat Metallic Casings Using the Contour Integral Method Inproceedings

2015 International Conference on Electromagnetics in Advanced Applications (ICEAA), Turin, Italy, September 07-11, 2015.

Links

Qi Wu, Alexander Vogt, Heinz-Dietrich Brüns, Frank Gronwald, Christian Schuster

Numerical and Experimental Evaluation of Electromagnetic Coupling between Radiating Antenna Structures inside a Computer Casing Inproceedings

2015 IEEE International Symposium on Electromagnetic Compatibility (EMC) Dresden, Germany, August 16-22, 2015.

Alexander Vogt

Solving highly resonant structures using a fast direct H-matrix solver in the method of moments Workshop

IEEE EMC International Symposium on Electromagnetic Compatibility, Dresden, Germany, August , 2015.

Alexander Vogt, Heinz-Dietrich Brüns

Modeling using MoM – Solving challenging realworld problems Workshop

IEEE EMC International Symposium on Electromagnetic Compatibility, Gothenburg, Sweden, September, 2014.

Alexander Vogt, Heinz-Dietrich Brüns, Christian Schuster

Einfluss von absorbierenden Materialien auf die elektromagnetische Strahlung von Leiterplatten Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) , Düsseldorf, Germany, March 11-13, 2014.

Alexander Vogt, Heinz-Dietrich Brüns, Helge Fielitz, Christian Schuster

Modeling Absorbing Materials in Cavities with Apertures Using the Thin Sheet Approximation Inproceedings

Asia-Pacific EMC Symposium (APEMC), Melbourne, Australia, May 20-23, 2013.

Links

Xiaomin Duan, Alexander Vogt, Heinz-Dietrich Brüns, Christian Schuster

Progress Towards a Combined CIM/MoM Approach for EMI Analysis of Electronic Systems Inproceedings

IEEE EMC Europe Symposium, Rome, Italy, September 17-21, 2012.

Links

Alexander Vogt, Heinz-Dietrich Brüns, Samuel Connor, Bruce Archambeault, Christian Schuster

Applicability of the Thin Sheet Approximation to the Analysis of EM Emission from Coated PCBs Inproceedings

IEEE EMC International Symposium on Electromagnetic Compatibility, Pittsburgh, USA, August 5-10, 2012.

Links

Application of the Characteristic Mode Analysis to Antenna Design and Electromagnetic Compatibility

Alexander-von-Humboldt Fellowship Prof. Qi Wu. 01.03.2014 – 29.02.2016

The Characteristic Mode Analysis (CMA) – based on the fundamental works of Harrington and Mautz – is a well-known numerical tool for antenna analysis and design. Within the numerical framework of the method of moments (MoM) the characteristic modes are found by the solution of a weighted matrix eigenvalue equation formulated with the MoM system matrix. The resulting current distributions are the eigencurrents and eigenvalues, respectively. The eigenvalues indicate if the corresponding eigencurrents may store primarily magnetic energy, or electric energy, or if they are “at resonance” and may radiate efficiently if excited. The eigencurrents constitute a set of (orthogonal) modes characteristic to the investigated structure (hence the name) and independent of any excitation. In antenna design inspection of the eigencurrents allows to identify e.g. suitable locations for generators and ways to improve radiation efficiency. In EMC analysis, the goals are opposite: analyze a potentially radiating structure and reduce its potential for emission.

During the Alexander von Humboldt Fellowship of Prof. Qi Wu at TUHH CMA was applied successfully to antenna design and extended to EMC analysis of digital systems. A full report of his fellowship is given in the following document PDF.

General procedure to perform the CMA of metallic radiators: the analysis is split into four steps. Image taken from: “Characteristic Mode Analysis of Radiating Structures in Digital Systems,” IEEE Electromagnetic Compatibility Magazine.

Eigencurrents in A/m and radiation eigenpatterns of a cubic heatsink on a motherboard at 500 MHz obtained by CONCEPT-II. Image taken from: “Characteristic Mode Analysis of Radiating Structures in Digital Systems,” IEEE Electromagnetic Compatibility Magazine.

Related Publications:

Qi Wu, Heinz-Dietrich Brüns, Christian Schuster

Characteristic Mode Analysis of Radiating Structures in Digital Systems Journal Article

IEEE Electromagnetic Compatibility Magazine , 5 (4), 2016.

Links

Qi Wu, Heinz-Dietrich Brüns, Christian Schuster

Evaluation of isolation between blade antennas in pre-design phase using a synthesized model Inproceedings

IEEE Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC), Shenzhen, China, May 18-21, 2016.

Links

Alexander Vogt, Heinz-Dietrich Brüns, Qi Wu, Frank Gronwald, Christian Schuster

A Measurement Setup for Quantification of Electromagnetic Interference in Metallic Casings Journal Article

IEEE Transactions on Electromagnetic Compatibility, 57 (6), 2015.

Links

Qi Wu, Alexander Vogt, Jan Birger Preibisch, Andreas Hardock, Heinz-Dietrich Brüns, Christian Schuster

Modeling of Mutual Coupling between Coaxial Probes in Flat Metallic Casings Using the Contour Integral Method Inproceedings

2015 International Conference on Electromagnetics in Advanced Applications (ICEAA), Turin, Italy, September 07-11, 2015.

Links

Qi Wu, Alexander Vogt, Heinz-Dietrich Brüns, Frank Gronwald, Christian Schuster

Numerical and Experimental Evaluation of Electromagnetic Coupling between Radiating Antenna Structures inside a Computer Casing Inproceedings

2015 IEEE International Symposium on Electromagnetic Compatibility (EMC) Dresden, Germany, August 16-22, 2015.

Qi Wu, W. Su

Rigorous Eigenmode Analysis of Conducting Sphere Inproceedings

2015 9th European Conference on Antennas and Propagation (EuCAP), Lisabon, Portugal, April 12-17 , 2015.

Qi Wu, Xiaojing Ding, Aixin Chen

A Broadband Dipole Antenna for Multi-Service Indoor Distributed Antenna System (MS-IDAS) Journal Article

IEEE Antennas and Wireless Propagation Letters, 14 , 2015.

Qi Wu, Xiaojing Ding, Donglin Su

Theoretic and Experimental Analysis of a Reflector-backed Dipole Antenna for 1-3 GHz EMC Test Inproceedings

IEEE International Symposium on Electromagnetic Compatibility, EMC Europe, Gothenburg, Sweden, September 1-4, 2014.

Links

Qi Wu, Siyuan Guo, Donglin Su

On the Eigenmodes of Small Conducting Objects Journal Article

IEEE Antennas and Wireless Propagation Letters, 13 , 2014.

Links

Accurate and Efficient Algorithms in the Method of Moments for the Analysis of High Intensity Radiated Field Coupling into Aircraft

Ph. D. Thesis Arne Schröder. 01.09.2009 – 31.08.2013

The evolution of electronic systems in aircraft emphasizes the importance for numerical simulations regarding electromagnetic field coupling into avionic systems. This thesis addresses accurate and efficient algorithms for a mehtod of moments based analysis of aircraft. The simulation efficiency for various problems is increased by exploiting redundancies in the initial numerical formulation. A coupled integral equation is introduced, enhancing the accuracy of the method of moments with regard to field coupling into aircraft. Various application examples, ranging from generic objects to real world aircraft, are used to proof the validity of these techniques and putting the attention on challenges arising from practical applications.

Surface current density on an aircraft under plane wave illumination (aircraft model courtesy of HIRF SE partner Evektor, Czech Republic). (Source: TET, TUHH).

Bistatic radar cross section (RCS) of aircraft to the left. The comparison of two diffrent computation methods shows good agreement. (Source: TET, TUHH). (Source: TET, TUHH).

Related Publications:

Fabian Happ, Arne Schröder, Gazmend Mavraj, Heinz-Dietrich Brüns, Frank Gronwald

Numerical Shielding Analysis of Anisotropic Multilayer Materials by the Method of Moments Journal Article

IEEE Transactions on Electromagnetic Compatibility, 1 , 2017.

Links

Arne Schröder

Accurate and Efficient Algorithms in the Method of Moments for the Analysis of High Intensity Radiated Field Coupling into Aircraft PhD Thesis

2014, ISBN: 978-3-8440-2899-7.

Arne Schröder, Heinz-Dietrich Brüns, Christian Schuster

Fast Evaluation of Electromagnatic Fields using a Parallelized Adaptive Cross Approximation Journal Article

IEEE Transactions on Antennas and Propagation, 62 (5), 2014.

Links

Mathias Magdowski, Arne Schröder, Heinz-Dietrich Brüns, Ralf Vick

Effiziente Simulation der Einkopplung statistischer Felder in Leitungsstrukturen mit der Momentenmethode Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) , Düsseldorf, Germany, March 11-13, 2014.

Arne Schröder, Guido A. Rasek, Heinz-Dietrich Brüns, Zdenek Reznicek, Jaromir Kucera, Steffen E. Loos, Christian Schuster

Analysis of High Intensity Radiated Field Coupling into Aircraft using the Method of Moments Journal Article

IEEE Transactions on Electromagnetic Compatibility, 56 (1), 2014.

Links

Fabian Happ, Arne Schröder, Heinz-Dietrich Brüns, Frank Gronwald

A Method for the Calculation of Electromagnetic Fields in the Presence of Thin Anisotropic Conductive Layers using the Method of Moments Inproceedings

EMC Europe 2013, Brugge, Belgium, September 2-6, 2013.

Arne Schröder, Heinz-Dietrich Brüns, Christian Schuster

A Hybrid Approach for Rapid Computation of Two-Dimensional Monostatic Radar Cross Section Problems With the Multilevel Fast Multipole Algorithm Journal Article

IEEE Transactions on Antennas and Propagation, 60 (12), 2012.

Links

Jesus Alvarez, Luis Diaz Angulo, Mauro Bandinelli, Heinz-Dietrich Brüns, M. A. Francavilla, Salvador González Garcia, Rodolfo Guidi, G. Gutierrez, C. Jones, M. Kunze, Jean-Paul P. Martinaud, Irina Munteanu, M. Panitz, Jean- Philippe P. Parmantier, Paola Pirinoli, Zdenek Reznícek, Gilles Salin, Arne Schröder, Pavel Tobola, Francesca Vipiana

HIRF Interaction with Metallic Aircrafts. A Comparison Between TD and FD Methods Inproceedings

International Symposium on Electromagnetic Compatibility (EMC Europe), Rome, Italy, September 17-21, 2012.

Links

Arne Schröder, Heinz-Dietrich Brüns, Christian Schuster

Efficient Compression of Far Field Matrices in Multipole Algorithms based on Spherical Harmonics and Radiating Modes Journal Article

Advanced Electromagnetics Symposium (AES), Paris, France , April 16-19 and Advanced Electromagnetics, 1 (2), 2012.

Links

Arne Schröder, Heinz-Dietrich Brüns, Christian Schuster

Beschleunigung schneller Löser in der Momentenmethode bei Einkopplungsproblemen mit Mehrfachanregung Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) , Düsseldorf, Germany, February 7-9, 2012.

Arne Schröder, Guido A. Rasek, Steffen E. Loos, Heinz-Dietrich Brüns, Christian Schuster

Numerical and Experimental Investigations on a Metallic Fuselage Model with Apertures Inproceedings

EMC Europe Conference, York, United Kingdom, September 26-30, 2011.

Arne Schröder, Heinz-Dietrich Brüns, Geoff South, Christian Schuster

Investigation of Field Coupling into a Carbon Fiber Aircraft Model with the Method of Moments Inproceedings

International Conference on Electromagnetics in Advanced Applications (ICEAA), Torino, Italy, September 12-16, 2011.

Arne Schröder, Heinz-Dietrich Brüns, Christian Schuster

Exploiting Planes of Magnetic Symmetry in the Fast Multipole Method Inproceedings

International Symposium on EMC Europe, Wroclaw, Poland, September 13-17, 2010.

Arne Schröder, Miguel Astner, Heinz-Dietrich Brüns, Christian Schuster

Ausnutzung magnetischer Symmetrie bei der numerischen Analyse von Feldproblemen mit der schnellen Multipolmethode Inproceedings

Internationale Fachmesse und Kongress für Elektromagnetische Verträglichkeit (EMV Düsseldorf) , Düsseldorf, Germany, March 9-11, 2010.

Development of a Full-Wave Module for the High Intensity Radiated Field (HIRF) Synthetic Environment

EU-Project. 01.12.2008 – 13.05.2013

The “HIRF Synthetic Environment”, financed by the EU with a total of 45 partners, research project had the goal to provide a numerical modelling framework to the aeronautic industry which can be used during the development phase of aircraft for prediction of adequate electromagnetic immunity. For this purpose several state-of-the-art computational electromagnetic codes were integrated into a common modeling platform and validated against each other and against measurements. From the part of the Institute of Electromagnetic Theory the MoM code CONCEPT-II could be successfully adapated and integrated into the synthetic environment.

In the future, the availability of such a HIRF Synthetic Environment framework becomes more and more significant in order to be able to cope with competing requirements of new designs, with the related increase of testing, and the general demand of costs and time reductions.

Surface current distribution on aircraft due to HIRF illumination calculated by CONCEPT-II (Source: TET, TUHH).