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International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / Telemetry operation is used extensively on a typical Department of Defense (DOD) test range to transfer data from an airborne transmitter to a ground receiver. The conventional telemetry systems employed are usually narrow-band systems. When a large number of airborne transmitters need to transfer data simultaneously to a ground station, a spread spectrum modulation scheme can be used. The drawback of such a scheme, however, is the large emission bandwidth required. The present frequency channeling plans in the telemetry band do not support frequency approval of large bandwidth data telemetry systems. However, a key requirement for obtaining the frequency approval can be satisfied if it can be shown that the spread spectrum modulated signal does not interfere with other systems in the same band. That is, the spread spectrum telemetry systems (SSTS’s) are feasible if these systems are electromagnetically compatible with the existing narrow-band telemetry receivers (NBTR’s) in their immediate environment. The electromagnetic compatibility (EMC between the SSTS transmitters and the conventional NBTR would promise the beginning of a new era for the telemetry operations on a DOD test range. This paper develops a methodology to establish the EMC between multiple airborne transmitters of an SSTS employing the code division multiple access (CDMA) technique and a ground-based conventional NBTR on a typical DOD test range operating simultaneously in the same band. The paper calculates the electromagnetic interference (EMI) levels between the SSTS and the NBTR to establish the EMC between the two systems.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005. / Due to the expensive nature of high frequency measurements in the EMC (Electromagnetic Compatability) field, more affordable methods of measurement instrumentation and environments are investigated. Different calibration methods for an Automatic Network Analyser (ANA) are evaluated against each other to determine the most cost-effective method of calibration. The mathematics for all the calibration methods are used in MATLAB programs which perform the error-calculation and correction which is usually done by the ANA software. These programs can be used to develop a simplified homebuilt ANA at reduced cost. The MATLAB program calibrations are compared to actual ANA calibrations to determine accuracy. Different measurement environments are considered as well to decide on a best compromise between cost and accuracy. To achieve this a reverberation chamber was built in which measurements were done and compared to measurements done on an Open Area Test Site. The Device Under Test was a standard radiator constructed specifically for such measurements. The development of both the radiator and the reverberation chamber are discussed and all the measurement results are considered in this thesis.

This document is a thesis submitted in partial fulfilment of the requirements of the University of Hertfordshire for the degree of Doctor of Philosophy (Part Time) in 'EMC in Wire-line Communications' in the School of Electronic, Communication and Electrical Engineering at the University of Hertfordshire. It describes a programme of research into the modelling and measurement of radio frequency interference emissions from various communication networks including Power Line (Tele)communications (PLC/PLT) and Digital Subscriber Line (DSL). An introduction and literature review are followed by the results of practical measurements on installed networks. These measurements include antenna gain and Longitudinal Conversion Loss (LCL). Power line communication networks, splitterless DSL and home phoneline networks in buildings are studied and modelled and the models are compared with the measured results. Improved EMC test methods are also described, in particular the modelling and design of four types of portable antennas for use in radiated EMC measurements with improved sensitivity at frequencies up to 30 MHz. The first type is a set of three manually tuned loop antennas covering 100 kHz - 30 MHz. The second is a set of three loop antennas that cover a similar frequency range but with remote tuning via an optical fibre link, under the control of software which also controls an EMC measuring receiver. The third type is a larger (1.6 m diameter) tuned loop covering 1.75 - 10 MHz that allows the measuring system noise floor to be below the typical atmospheric noise floor. The fourth type is an electrically short dipole covering 10 - 30 MHz with improved matching. The protection requirements for various types of radio communication services are analysed and are compared with emission levels from various types of wireline communication network. A review of existing applicable EMC standards and standards under development is also presented.

La cohabitaion, dans une même enceinte, des systèmes électroniques de puissance et decommande est un risque majeur pour le bon fonctionnement des systèmes électroniquesembarqués (Automobile, Aéronautique et Spatial). La maitrise de la CEM de ces systèmes estun défit surtout avec la difficulté de rendre compte des phénomènes EM.Ce mémoire décrit la modélisation des émissions conduites et des émissions EM rayonnéespar le câblage des systèmes électroniques embarqués. On explique d’abord le choix del’utilisation de la méthode de modélisation PEEC puis on décrit sa formulationmathématique et on présente les différents phénomènes EM qu’elle prend en compte dansle contexte de câblage.Dans le deuxième chapitre, un calcul tridimensionnel des émissions EM rayonnées a étéproposé. Il prend en compte de la géometrie des cellules de discrétisation et permet unemeilleure considération de la montée en fréquence. Il permet ainsi de se rapprocher au plusprès de la structure. Une validation de ce calcul a été effectuée en comparant les résultatsde simulation à ceux obtenus par d’autres calculs analytiques, par modélisation « élémentsfinis » et aussi par des mesures en champ proche.Le troisième chapitre est consacré aux applications aux systèmes électroniques embarqués.Dans une première partie, une étude d’un système de câblage, qui reflète les différentsphénomènes rencontrés en automobile, a été faite. Ensuite, un câblage est associé à unconvertisseur DC/DC. Ce convertisseur est utilisé comme un générateur de perturbations EMen Hautes fréquences. Dans cette partie du travail, on présente une modélisation de cesperturbations qui se propagent vers le câblage et qui se transforment en émissions EMrayonnées. / The calculation of radiated electromagnetic (EM) fields from wiring systems such as cables in automotive/aeronautic applications is an important issue for the prediction and the prevention of EM Interference (EMI) and EM Compatibility (EMC) problems. Many numericalmethods of electromagnetic modeling are available and can be used for EM analysis. Amongthese methods, the Partial Element Equivalent Circuit method (PEEC) is particularly wellsuited. Usually the PEEC approach is an efficient way to deal with circuit simulation ofdistributed structures. In automotive/aeronautic applications, the electronic systemsoperate at increasingly higher frequencies. So, the radiation of cables cannot be neglected. A3D model based on the PEEC method was proposed in order to take into account the size ofautomotive wiring systems. It includes resistive, inductive and capacitive effects. This 3Dapproach was shown to accurately predict the conducted disturbances by cables above largeground planes.In this work a new 3D calculation approach based on Maclaurin expansion is developed toevaluate the radiated fields with the PEEC method. The originality of this work is consideringboth radiated and conducted disturbances in the framework of a PEEC method for large sizestrcutures. In a first step the current carried by the conductors are determined from thecircuit model deduced with the 3D PEEC method. Then in a second step the field radiated bythe wiring systems is evaluated using an analytical calculation deduced from the distributionof currents.The third part of this work is to identify the disturbances generated

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Cette thèse se situe dans le domaine de l'électromagnétisme et plus particulièrement, celui de la compatibilité électromagnétique. L'objectif de cette thèse est de proposer une condition d'interface qui évite de mailler les plaques minces conductrices lors d’une modélisation tridimensionnelle. Cette condition permet de prendre en compte de manière précise la réflexion d'une onde ou sa transmission par une plaque conductrice. Elle permet aussi de tenir compte de l'effet de peau de l'effet de peau à l'intérieur de la plaque. Cette condition d'interface est intégrée dans une méthode Galerkin discontinue. La présence des termes de flux dans cette méthode rend facile l'implémentation de cette condition d'interface. Afin de montrer l'intérêt de cette condition dans le cadre de la compatibilité électromagnétique, des configurations d'interaction ondes-Structures sont traitées. Elles ont pour but d'étudier l'efficacité de blindage de diverses cavités bidimensionnelles et tridimensionnelles. / This thesis concerns electromagnetic fields and more particularly electromagnetic compatibility. The aim of this thesis is the modeling an interface condition to avoid the mesh of thin conductive sheets in 3D numerical methods. This interface condition allows to take in account the reflection or the transmission of an incident wave on a conductive sheet. It also takes into account the skin effect in this sheet. This interface condition is integrated in discontinuous Galerkin method. The presence of flux terms is this method makes easy to implement this interface condition. To demonstrate the advantage of this interface condition in electromagnetic compatibility problems, many configurations of interaction wave-Structure are treated. They aim to study the shielding effectiveness of different cavities in two and three dimensions.

Este trabalho propõe uma configuração de câmaras excitadas por linhas de transmissão, considerada como potencial solução para as restrições das câmaras reverberantes atuais. Dentre estas restrições menciona-se, por exemplo, as relativas à operação das câmaras em baixas frequências, cujas dimensões poderão representar uma restrição física à sua implementação em ambientes de teste. Outras características físicas podem ser consideradas também restritivas, ao se considerar o volume útil de trabalho e o modo de excitação das câmaras canônicas. Visando satisfazer os índices de mérito aplicáveis, as diversas configurações propostas são avaliadas, onde, além dos arranjos das linhas de transmissão, também são considerados os detalhes relativos às variações da excitação e da carga via controle eletrônico. A metodologia de análise de desempenho da câmara proposta utiliza, basicamente, métodos analíticos, numéricos e avaliações experimentais. A aplicação de algoritmos e métodos de otimização recomendados pela literatura atual e alguns procedimentos desenvolvidos e adaptados pelos autores, foram utilizados na busca de configurações que melhor satisfaçam os índices de mérito adotados. Diversos resultados, obtidos através de simulações numéricas e de avaliações experimentais realizadas em um protótipo são apresentados e comparados, visando uma análise das potencialidades e da aplicabilidade deste tipo de câmara às necessidades dos ensaios de compatibilidade eletromagnética de equipamentos e sistemas elétricos e eletrônicos. / This Thesis presents the proposition of a Transmission Line Excited Chamber configuration. This configuration is considered to be a potential solution for the constraints of reverberation chambers of nowadays. Among this constraints, e.g. the ones related to chamber operation at some MHz, is a physical restriction to implement in tests environments. Moreover the work volume and the canonical chamber excitation ways are also considered restrictions. In order to satisfy the chamber evaluation indexes of merit applicability, several transmission line sets are evaluated, including the details concerned to electronic exciting variation and load variation. The chamber performance analysis methodology is proposed in this work is based on analytical and numerical methods, and also experimental evaluations. Not only optimization algorithms and methods recommended by literature were used in order to reach the adopted indexes of merit but also procedures developed and adapted by the authors. To analyze the chamber capacity to reach all the electromagnetic compatibility test requirements applied to equipments and electric and electronic systems, several tests, were performed over one Transmission Line Excited Chamber prototype. The results obtained by numerical simulations and experimental evaluations are presented and compared.

Neste trabalho apresentar-se-á um método para a determinação de modelos simplificados de fontes equivalentes de campos elétricos e magnéticos aplicáveis à análise de compatibilidade eletromagnética de sistemas embarcados. Esses modelos são obtidos a partir de medições laboratoriais, com técnicas de cálculos analíticos, numéricos e híbridos. Destacam-se, o fato da utilização do método de medição através de antenas de grandes loops (ou, laços, em português), na determinação de fontes equivalentes de emissão radiada e a aplicação destas na avaliação dos campos eletromagnéticos radiados. A contribuição deste trabalho é a obtenção dessas fontes equivalentes de emissão radiada, que possibilitam a avaliação da contribuição dos campos elétricos e magnéticos em ambientes eletromagnéticos. E também contribui com a aplicação de uma metodologia para a obtenção dos campos elétricos a partir dos campos magnéticos previamente determinados. Em particular, este trabalho pode ser considerado como decorrente da evolução da Dissertação de Mestrado [1]. / It will be shown in this work a method for simplified models determination of equivalent sources for electric and magnetic fields, applicable to embedded systems electromagnetic compatibility analysis. These models are obtained by laboratory tests with analytical calculation techniques associated to numerical and hybrid calculations. This work highlights the application of measurement method by Large Loop Antennas (LLAs) for the creation of radiated emission equivalent sources and the application of a corresponding method for obtaining radiated electromagnetic fields. The contribution of this work is the acquisition of these equivalent sources of radiated emission, which allows the evaluation of the magnetic and electric field contribution in electromagnetic environments. And it also contributes with the application of a methodology to obtain the electric fields from previously determined magnetic fields. In special, this work may be considered as an evolution of the Master\'s Thesis [1]

by Hung King Fai Kevin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 82-85 (2nd gp.)). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.ii / ABSTRACT --- p.iii / 摘要 --- p.v / TABLE OF CONTENTS --- p.vi / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- OBJECTIVES --- p.1 / Chapter 1.2 --- NEED FOR PATIENT-MONITORING SYSTEM --- p.1 / Chapter 1.2.1 --- Aging Population --- p.1 / Chapter 1.2.2 --- Increasing Population with Heart Diseases --- p.2 / Chapter 1.3 --- ECG BASICS --- p.3 / Chapter 1.4 --- EXISITING ECG-MONITORING TECHNOLOGIES --- p.4 / Chapter 1.5 --- CHALLENGES IN PATIENT-MONITORING --- p.5 / Chapter 1.6 --- DEVELOPMENT OF AN ECG-MONITORING SYSTEM --- p.6 / Chapter 1.6.1 --- Overall Structure --- p.6 / Chapter 1.6.2 --- Considerations --- p.7 / Chapter CHAPTER 2 --- EMI FILTERS IN ECG ACQUISITION CIRCUIT --- p.8 / Chapter 2.1 --- OVERVIEW OF NOISE SOURCES IN ECG ACQUISITION --- p.8 / Chapter 2.1.1 --- Other Biopotentials --- p.8 / Chapter 2.1.2 --- Motion Artifact --- p.8 / Chapter 2.1.3 --- Power-line Interference --- p.10 / Chapter 2.1.4 --- High-Frequency Electromagnetic Interference --- p.15 / Chapter 2.2 --- EMI FILTERS --- p.16 / Chapter 2.2.1 --- Introduction to EMI Filters --- p.16 / Chapter 2.2.2 --- Types of EMI Filter --- p.17 / Chapter 2.2.3 --- EMI Filters in ECG Monitoring --- p.21 / Chapter 2.3 --- MODELING OF INTERFERENCE IN ECG-MONITORING SYSTEM --- p.22 / Chapter 2.3.1 --- Model and Parameters --- p.22 / Chapter 2.3.2 --- Method --- p.24 / Chapter 2.3.2 --- Results --- p.27 / Chapter 2.3.3 --- Discussion --- p.30 / Chapter 2.4 --- BUILDING AN ECG ACQUISITION CIRCUIT WITH EMI FILTERS --- p.30 / Chapter 2.4.1 --- Purpose --- p.30 / Chapter 2.4.2 --- Experimental Setup and Method --- p.30 / Chapter 2.4.3 --- Results --- p.32 / Chapter 2.4.4 --- Discussion --- p.46 / Chapter CHAPTER 3 --- ADAPTIVE FILTER --- p.48 / Chapter 3.1 --- OBJECTIVE --- p.48 / Chapter 3.2 --- INTRODUCTION TO ADAPTIVE FILTER --- p.48 / Chapter 3.3 --- METHOD --- p.50 / Chapter 3.4 --- RESULTS --- p.52 / Chapter 3.5 --- DISCUSSION --- p.57 / Chapter CHAPTER 4 --- WAP-BASED TELEMEDICINE APPLICATIONS --- p.59 / Chapter 4.1 --- INTRODUCTION TO TELEMEDICINE --- p.59 / Chapter 4.2 --- INTRODUCTION TO WAP --- p.59 / Chapter 4.3 --- WAP APPLICATIONS --- p.60 / Chapter 4.4 --- SYSTEM IMPLEMENTATION --- p.63 / Chapter 4.4.1 --- Overall Structure --- p.63 / Chapter 4.4.2 --- Relational Database --- p.63 / Chapter 4.4.3 --- Program Flow --- p.64 / Chapter 4.4.4 --- ECG Browsing and Feature Extraction --- p.70 / Chapter 4.5 --- EMULATION --- p.72 / Chapter 4.6 --- EXPERIENCE WITH WAP PHONE --- p.74 / Chapter 4.7 --- DISCUSSION AND CONCLUSION --- p.75 / Chapter CHAPTER 5: --- CONCLUSION AND FUTURE WORK --- p.77 / Chapter 5.1 --- CONCLUSION --- p.77 / Chapter 5.2 --- FUTURE WORK --- p.77 / Chapter 5.3 --- MARKET ANALYSIS --- p.79 / BIBLIOGRAPHY --- p.80