How to . improve EMC performances of cable installations. The major conclusion from the study is that cable trays are an integral part of the ground structure (actually, it forms the ground if correctly done; nothing else is needed), which can perform as a shielding structure for the enclosed electronic systems. The major quality parameter […]
Michel Mardiguian . Electro Magnetic Interference (EMI) is the generic term describing a situation whereas an electrical disturbance generated by a certain electronic/electrical equipment is causing an undesirable response to another equipment. This undesirable effect may range from a mere nuisance to a catastrophic failure, with associated financial losses or eventually human casualties. The origin of the disturbance could also be a natural phenomena like lightning strokes or ElectroStatic Discharges (ESD). ElectroMagnetic Compatibility (EMC) is just the opposite: EMI being the disease, EMC is the cure, that is the discipline analyzing and preventing or fixing interference problems.
EYE ON . One fundamental concept in EMC design is zoning. Zoning is easy to understand. It is used in the most varied contexts and situations. Situations covering everything from old communist dictatorships, such as for example the former East Germany (DDR), to city planners and the European Union. Zones are used in order to achieve various properties in demarcated geographic areas, or within volumes. Zoning with application in electronic engineering are also known as the Controlled Electromagnetic Topology.
EYE ON . EMC is a complex topic. To achieve the desired EMC characteristics of a product, in an efficient way, often requires collaboration between different professional groups. In addition to electronics designers, all parties involved should have the understanding and basic knowledge of the subject. The most concerned may be: mechanical designers, project managers, machine builders, installers, and others.
A new product . must comply with certain EMC requirements in order to fulfill the essential requirements in the EMC directive. Mostly we take it for granted the product maintains its EMC performance through its entire lifetime. From sometimes bitter experience we know that our dear products fail occasionally, needing repair or replacement. Most people relate failure to loss of function but loss of EMC performance can also occur.
Background . PIM is an acronym for Passive InterModulation, an interference problem in wireless systems. The problem is not new, but has been known since long time back by designers of, for instance cell phone systems, space probes, connectors, coaxial cables, antennas and filters. The problem most frequently occurs, when dealing with high RF-currents in confined spaces. In this text, the basic theories behind PIM will be briefly discussed.
Abstract . The possible threat of a high-power microwave (HPM) weapon that destroys electronic equipment or its function is today taken seriously, and test methods and test standards are slowly adapted to this situation. However, a complete standard methodology for destructive HPM testing of complex electronic systems does not exist. In this article, the current status of relevant standards is reviewed, and FOIs ongoing work to contribute to the development of an up-to-date standard is mentioned.
An editor’s reflections . The total number of mobile subscriptions in the world is now as big as the world’s population. At the same time actors in the mobile communication industry have launched a vision that makes today’s mobile use appear only as a starting point. After the third and fourth generation mobile systems such developments are now underway to the fifth generation, 5G.
An editor’s reflections . The EMC area was born about a hundred years ago, when radio broadcasts began. At that time there was a concern that electromagnetic interference signals from electrical household equipment in could interfere with the reception of the new service.
FOI is establishing a facility . for destructive HPM testing and is developing an envisaged test methodology for such tests. The methodology consists of two test phases: (1) Determine the lowest power density required to destroy an object within a frequency range, using a reverberation chamber. (2) At this frequency, determine the most sensitive direction of attack using an HPM generator. A reverberation chamber and an HPM-generator adequate for such tests are presented together with early results from destructive testing of electronic systems in a reverberation chamber.