Communication Systems and Electromagnetic Compatibility - Dissertation Example

Communication Systems and Electromagnetic Compatibility Introduction: In the present times, the use of digital systems and IT has immensely increased in manufacturing facilities for different business organizations. The use of power systems supply has been found to be significantly powerful on one hand. This involves the increasing electromagnetic interference. On the other hand, expansions in digital networks have been obtained that reflect higher level of sensitivity. Their performances produce transfers of data that are high in rates and are used for tasks associated with safety measures. All these factors have increased the need for electronic installations of high quality in all the buildings as initiation of electromagnetic non-compatibility entails high costs often involving lesser maintenance of safety as well (Langguth and Wirtschaft, 1). As described by Radasky in his studies, “electromagnetic compatibility describes a state in which the electromagnetic environments produced by natural phenomena and by other electrical and electronic devices do not cause interference in electronic equipment and systems of interest” (Radasky). EMC plays an increasingly important part in the design of electronic products and systems. There is a need to understand EMC in order to prevent the interferences. The present study focuses on a discussion of the techniques and practices used in electrical design of different systems and electrical parts to augment the probability of the ultimate system becoming acquiescent to the EMC order. The distinct system elements would be discussed in the study that include the safety critical systems, the control and data connectivity issues, the power and UPS system, as well as recognition of good EMC design and strategies to combat any unforeseen problems associated with EMC. EMC Design and Its Application: EMC in the present times focuses more on standardization. This is particularly in relation to international organizations. The international standards are significantly taken concern of as a result of the requirements of the Worlds Trade Center that has made it clear to reduce the trade barriers across the globe and thus have strong emphasis on the standards (Radasky). The purpose of EMC is to ensure tolerance of different equipments or systems of particular interferences such that the level of generation of the interference does not exceed a particular level (Colotti, 3). The escalating intricacy of automotive electrical systems, accompanied with the requirements for lower emissions of RF and increased resistance to disturbances form electromagnetic waves, has steadily increased the issues of electromagnetic compatibility. As the growing demands for EMC support increase, there are a wide range of services made available to industries that enable a complete package of engineering. Such services include PCB design, wire harness design and routing evaluation, EMC filter design and manufacture, EM simulation in support of module placement, packaging design, audio system interference resolution, and EMC problem resolution (Electromagnetic Compatibility Design). PCB Design: Making use of miniaturization parts in the design of electronic equipment leading to the introduction of new technique in inter-component electrical system and congregation is referred as a printed circuit board or PCB (PCB Design| PCB Assembly). Some of the features those are relevant to this design include 100 percent netlist testing, signal integrity modeling, HDI technology, more than 36 layers, aspect ratios greater than 12:1, as well as electrical test and development (PCB Production Capabilities/ Design and Engineering Services/ Materials and Surface Finishes). Wire Harness Design and Routing Evaluation: Wire harness designs may be built up either manually or automatically. While preparing it automatically, a new list is made through ECAD system. The Harness Wizard command is used to bring in the file of the net list to Solid Edge to allocate part, association, and terminal information for the design of the harness. Other commands are used to place the components appropriately. Route wires and cables are bundled and used as needed. Also, the conductors are all tested. In the manual process, the assembly is built using the components. The wires and the cables are created. Then the cables and routes and bundled and used and the conductors are also verified (Creating a Wire Harness with Harness Design, 2). EMC Filter Design and Manufacture: EMC filter may be tailored suiting the particular environment of the systems. The environmental specification may be adjusted accordingly around Def Stan 00-35. The filter solutions of EMC are applicable on HVAC and blower motors, DC/DC power converters, engine and gearbox control systems, wiper systems, indicators, and alternator whine removal (EMC Filter Design and Manufacture). EM Simulation in Support of Module Placement: The rationale behind the use of an electromagnetic simulator is to obtain an estimated explanation to the equations given by Maxwell thus satisfying a specified set of margin conditions and initial conditions. Creation of the physical model involves formation of the outline geometry jointly with the classification and tasks of properties of objects to objects restricted within the outline of the geometry. The levels of the simulation are explained and the conditions of the restrictions are given by the setup of the EM simulation. In order to perform the simulation action, mesh cells are used in the geometrical layout or physical model of the system. A local function is applied to fairly accurate the current passing through the mesh cells, which is also known as the expansion of basis function. The coefficients of the function are attuned to satisfy the conditions of the boundary (Morris, 5). Packaging Design: EMC packaging design deals with the concerns of EMI/EMC while designing an area of enclosed space. According to the need of the space, instructions are given for constructing a profitable area and forecasting its shield performance (Design Services). Audio System Interference Resolution: There are certain basic problems related to obtaining an interference free system of audio. These include very few components being available that can be complied with the EM. Moreover the number of buildings is few with completely latticed earth conductor electric wiring that may be considered not to exist. Thus audio engineers and system integrators are taking greater interests in the system components of EM and on their designs (Waldron). EMC Problem Resolution: The best possible ways to solve problems related to EM system involves locating the basic group among the known groups and realize where the interference falls in (Introducing the EMC Newsletter, 1). After determining that, the designer can hold back the production at the point of the source, decrease the competence of the cables or air that form the coupling path that might also lessen the effect of propensity on the system. In general the source of emission cannot be controlled by the designer and hence needs to depend on measures that may lead to lesser susceptibility of the path making it inefficient (Introducing the EMC Newsletter, 1). System Analysis and EMC Issues: The process of systems analysis involves studying of a particular system, in this case meaning electronic system, by breaking down its parts. Thus the components are studied individually to see their relation and connectivity. Conventionally, systems analysis is coupled with projects of application development that include projects generating information systems and their linked applications of the computer and electronic systems. Certain strategies or techniques are available for implementing the act of systems analysis. These include: “modern structured analysis, information engineering, prototyping, and object-oriented analysis” (Systems Analysis). These strategies often prove to be competitors of each other (Systems Analysis). System Components Safety Critical Systems: Considering the issues of safety, the 6 dB margin has been found to be highly suitable for use. These values of margin have been suggested by studies to be sufficient for systems safety and performance. These are also strictly attainable through knowledge and understanding of the systems over a long period of time. Hence the application of these proves to be essential (Lawton, 4). The Control and Data Connectivity Issues: Data being the most important asset of any organization, the connectivity of such data and their control measures prove to be extremely necessary. This may be achieved through audit of the security measures of the manufacturing facilities and of the storage area network of EMC (Chapman, 4). The Power and UPS System: With the increasing use of computer systems in the electronic systems, the importance of computing devices has increased in the present times. If power supplies are unpredictable, then it creates a severe danger to the dependability and stability of data.  Thus there is need for protection of data for the person who remains in charge of the information, including the UPS. The role of the UPS involves storing energy into batteries and converting them into stored DC from where it gets converted into an AC supply.  Switching technique is used as result of which the current of switching produces electromagnetic discharge affecting the products in close proximity.  The emission created from UPS my include radiation or conduction or both.  Highly developed technologies of UPS are also responsive and for this reason necessitate greater resistance from Electromagnetic noise. Owing to the dependency of the computer systems on UPS, there is a need for immunity of the UPS to noise of power or any disturbances. Thus the EMI assessment of UPS is highly essential to make sure that the system works adequately in the proposed setting (EMC Evaluation and Analysis of UPS). EMC Design and Strategies to Combat EMC Problems: The effectiveness of EMC design has become a significant concern in the present times. The problems associated with EMC are classified as Conducted Emissions, Radiated Emissions, Conducted Susceptibility, and Radiated Susceptibility. The ability of a component of the EMC system such that it can operate either as a conductor or as a radiator, depends on the electrical measurement of the component. This dimension is again dependent on the physical size of the system component, as well as the frequency and wavelength of the occurrence of the operation (Electromagnetic Compatibility). General Issues of EMC: Electromagnetic interference (EMI) is being emitted in the present times from almost all electrical and electronic technologies. These emissions have the capability to interfere with the accurate process of radio communications and other electronics. The emissions are more likely in modern electronic technologies as can be expected to be at higher levels and higher frequencies than the case was in earlier times. Thus, all electronics (and software) can undergo corrupted functionality if they are out in the open to interference. The present day electronic devices are typically more predisposed than the systems of the earlier times (EMC for Functional Safety). Being more susceptible and the increasing use of today’s electronic technologies, the EM atmosphere is becoming more contaminated with the passing days. Following these trends, it is gradually more possible that inaccuracies and failures in operations of electronics and software owing to insufficient EMC will lead to augmented risks of safety (EMC for Functional Safety). Potential Solutions to EMC Problems: The problems related to EMC might often be hidden by the performances of other equipments and operations. The overall compatibility within the EMC system is determined by the complicated relationship that exists between the layout of the circuits, the bandwidth, the grounding as well as the shielding that play a major role in the electromagnetic atmosphere. In order to realize the problems in such an environment, the unpredictable or unexplained behavior of the system needs to be recognized. This could be some form of malfunction that might be activated by the performances of other equipments in the environment, even if the functions of the two instruments may be different (What is EMC?). Problems related to EMC might also be enhanced through natural incidents like lighting or electrostatic discharge. These are more initiated if the systems are susceptible in nature. It has been observed that when there is an EMC problem, it is always accompanied by an interference from a particular point of source, which might be a circuit being the victim. Also, a coupling path is involved in the process. The best way to repair the system is to recognize the problem as early as possible, diagnose it systematically and implement practical solutions on it to reduce the problem to a simpler issue. In this regard consultation with a qualified professional of EMC is necessary (What is EMC?). With the growing problems of the EMC, there is a need for measures to tackle the problems and lead to potential solutions. The European Commission adopted the EMS directive on January, 1st, 1992, as part of the new approach directives, that was focused to deal with the growing number of conflicts associated with EM. The major intention was to facilitate the movement of goods without charges within the EU by setting up technological necessities for producers in different locations (What is EMC?). The Directive had included the following as parts of its measures: "the electromagnetic disturbance it generates does not exceed a level allowing radio and telecommunications equipment and other apparatus to operate as intended... the apparatus has an adequate level of intrinsic immunity to electromagnetic disturbance to enable it to operate as intended... Conformity is demonstrated by use of the "CE" mark. This will also indicate conformity with the European directive covering safety, as well as a number of other directives should they be applicable. It is an offence to knowingly supply "CE-labelled" goods that do not meet the requirements of the directives. Such an offence could result in fines, removal of goods from the market, as well as legal action against individuals within your company” (What is EMC?). EDRA Evaluation: EDRA or EMC Design Risk Assessment has some technical recommendations for EMC. The EDRA makes available both techniques involving qualitative and quantitative measures for evaluating the collision of changes in the individual designs of products design on the conformity condition of a product.  The technique has been considered depending on Design Failure Mode and Effect Analysis (DFMEA). It is a technique used comprehensively in the industries of aerospace and automotive electronics and as a result it needs to be well-known to engineers working in these areas.  A source in obtainable engineering practice requires facilitating the system to increase integrity with DFMEA supporters, accompanied with beginners to the use of the system being offered some self-assurance that the method has a standard in other areas (O’Hara). The technique of EDRA constitutes 4 different classes of risk the effect of which are implied. These categories have numeric range to designate the degree of risk associated with EMC. The technique is as follows: “The impact assessment is a simpler 3-category multiplier based on the circuit application of the change.  The risk factor is multiplied by the impact factor for each proposed change. Consequently a simple change such as a change in a bias resistor value has in itself a low risk on system EMC performance.  However, if this bias resistor is connected to an I/O circuit there is the potential that this will reduce the immunity of that circuit hence has a greater impact than if this is simply holding up an unused internal logic gate.  It is also important to include changes that have no implied EMC risk, such as change in temperature performance, as this demonstrates that the change was considered and assessed to have no effect. The category values are open to discussion and may be set for specific industries, values quoted here should be appropriate for an electronic module of moderate complexity (e.g. PC plug-in card or similar sized electronic controller).  Highly complex, higher component density systems (e.g. complete PC’s or instrumentation systems) may use slightly higher threshold values as higher component count systems may be less affected by single component changes” (O’Hara). Conclusion: From the above study, it may be concluded that with the changing use of electronic systems and computing mechanisms in industries in the present times, the design and proper use of EMC holds significant importance for instruments and in organizations. Thus effects of the design and the probable faults, errors and problems associated with the EMC need to be understood well in order to implement measures to make correct use of the EMC. This would then allow the relief of the instruments and equipments for the issue of interferences. With the increasing need for EMC, the potential solutions for the problems are also being processed and discovered. Here it may be recommended that the EDRA measure needs to be well understood and applied within organizations such that the design changes on the EMC system may be analyzed with the use of a low cost measure as it proves to be complaint in its use. Thus whether design changes would affect the system, or would prove to be effective may be evaluated, thereby trying to implement a good practice and design of EMC system within organizations and in use of electronic systems. 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