IEMI refers to the deliberate attempt to produce EMI to interfere with commercial equipment. Dr. William A. Radasky, Ph.D. Metatech Corporation, Goleta, CA INTRODUCTION Over the past few years several articles have been written by this author and others indicating the threat and importance of intentional electromagnetic interference (IEMI).1–4 Since the publication of the … [Read more...]
First Amendment to the International Standard for EMC on Medical Devices
Amendment 1 to IEC 60601-1-2 is worth a careful reading by anyone involved in the design, manufacturing and/or testing of electrical medical equipment. Daniel D. Hoolihan Hoolihan EMC Consulting, Lindstrom, MN In September of 2004, the International Electrotechnical Commission (IEC) released Amendment 1 to the Second Edition of IEC 60601-1-2. This Amendment was prepared by … [Read more...]
EMC Assessment of Programmable Controllers: Choosing the Appropriate Standards
Using out-dated standards may result in erroneous conclusions regarding the true electromagnetic compatibility of the device under test. Nikolai Panteleev and Borislava Medzhidieva EMC Testing Laboratory, Sofia, Bulgaria Programmable logic controllers (PLCs) are widely used in industrial control systems for several reasons. Using specialized languages, they are easy to … [Read more...]
Achieving EMC in Pharmaceutical Industry Equipment – A Case Study
The many devices used in an industrial setting can present significant challenges in emissions control. Vinod Kumar Dhar Electronics Regional Test Laboratory (West), Indian Ministry of Information Technology, Mumbai, India While controlling electromagnetic interference is a worldwide challenge encountered in homes, shops, and offices, that task can be particularly difficult … [Read more...]
Selecting Antenna/Power Amplifier Combinations for the Coming New RF Immunity Standards
Though far from certain, it looks as if 6 GHz is a strong candidate for the upper frequency for consumer products. Art Cohen A.H. Systems, Inc., Chatsworth, CA, USA Thomas Mullineaux Empower RF Systems, Inc. Inglewood, CA, USA Testing products for susceptibility to radiated fields above 1 GHz is on the horizon. The new medical standard now stipulates testing to 2.5 GHz, and … [Read more...]
HIRF Testing in an Anechoic Chamber
A detailed examination of radiated field and transmitted power test techniques MICHEL LE CLECH, EMITECH ABSTRACT HIGH PULSED E-FIELD TEST LEVELS increased at the end of the 1990s. At the same time, many efforts were made to develop a very efficient test technique with the mode-stirred chamber. However, by improving the antenna design and test distances, comparable levels can … [Read more...]
Aspects of Conductive Filler Loading on EMI Shielding and DC Volume Resistivity
Brian W. Callen, B. Sc., Ph.D. and Claudia E. Johnston Westaim Ambeon, Fort Saskatchewan, Alberta, Canada Dennis K. Morland, P. Eng., M.Sc. The Northern Alberta Institute of Technology, Edmonton, Alberta, Canada INTRODUCTION Conductive fillers for plastics have been used in EMI shielding applications for many years. Initially pure metallic powders such as nickel or copper … [Read more...]
Antenna Polarization Measurements
Losses can arise from polarization mismatches. Ricardo Perez Alion Science and Technology, Annapolis, MD Antenna polarization is one of many parameters to consider when designing a system. The polarization of the transmitter antenna in a system should be properly aligned with the receiver antenna to maximize coupling. Maximum signal coupling between stations occurs when both … [Read more...]
Coping with Reflected Power in RF Immunity Systems
EMC system engineers face trade-offs when selecting high power amplifiers for RF immunity testing. During testing, the amplifier must withstand high levels of reflected power. An appreciation of how reflected power affects an amplifier is important if well-informed decisions are to be made. This article uses a simple thought experiment to de-mystify this complex phenomenon and … [Read more...]
Integrated Inductive Component Reduces Radiated Emissions in Power Applications
The geometry of magnetic components can affect the incidence of unwanted low frequency radiation in the magnetic field. Gabriel Arianes, David Castillo, Raquel Garcia and Oscar Perez; Ferroxcube, Guadalajara, Spain INTRODUCTION The miniaturization trend has resulted in smaller components and greater board densities in electronic applications. This very density, which … [Read more...]