Overview of PCB EMC Expert System Algorithms

Computer modeling software based on Electromagnetic Compatibility (EMC) expert system algorithms can be used to identify problems with a printed circuit board layout before the first hardware is built. Unlike numerical EM modeling software (which solves for fields due to specific structures) or EMC design rule checkers (which look for layout features that violate selected design guidelines), expert system tools examine boards in much the same manner as a professional EMC engineer. They evaluate possible EMI sources, coupling paths and antennas, then identify and rank potential EMC problems.

An expert system provides assistance to the non-expert, by identifying potential problems and helping to guide the designer towards possible solutions. Expert systems are also useful tools for experienced EMC engineers, because they can process an enormous amount of information quickly, allowing human experts to focus their attention on the specific problems identified by the software [1] - [7].

Expert system algorithms to evaluate and identify EMC problems with printed circuit board (PCB) designs have been developed and are described in the literature [2], [3], [7], [8]. These algorithms analyze printed circuit board sources and structures to estimate the maximum likely radiated emissions due to a particular coupling mechanism. The purpose of these estimates is not to predict the results of an EMI test, but rather to determine whether a particular feature of the board layout is likely to result in an EMI problem.

References

[1] K. Nageswara Rao, P. Venkata Ramana, M. V. Krishnamurthy, K. Zinnias, “ EMC analysis in PCB designs using an expert system,” Electromagnetic Interference and Compatibility, 1995 International Conference, Madras, India, Dec. 1995, pp. 59-62.

[2] T. Hubing, J. Drewniak, T. Van Doren and N. Kashyap, “An expert system approach to EMC modeling,” Proc. 1996 IEEE Int. Symp. Electromag. Compat., Santa Clara, CA, Aug. 1996, pp. 200-203.

[3] N. Kashyap, T. Hubing, J. Drewniak and T. Van Doren, “An expert system for predicting radiated EMI from PCB’s,” Proc. 1997 IEEE Int. Symp. Electromag. Compat., Aug. 1997, pp. 444-449.

[4] Drozd, A. Pesta, D. Wiener, P. Varshney and I. Demirkiran, “Application and demonstration of a knowledge-based approach to interference rejection for EMC”, in Proc. 1998 IEEE Int. Symp. Electromag. Compat., Aug. 1998, pp. 537-542.

[5] Demirkiran, V. N. S. Samarasooriva, P. K. Varshney, D. D. Weiner, R. Mani, S. Hamid Nawab and S. Tyler, “Knowledge-based approach to interference rejection for EMC,” Proc. 1998 IEEE Int. Symp. Electromag. Compat., Aug. 1998, pp. 1150-1155.

[6] S. Ranganathan, D. Beetner, R. Wiese and T. Hubing, “An expert system architecture to detect system-level automotive EMC problems,” Proc. 2002 IEEE Int. Symp. Electromag. Compat., Minneapolis, MN, Aug. 2002, pp. 976-981.

[7] H. Shim, T. Hubing, T. Van Doren, R. DuBroff, J. Drewniak, D. Pommerenke and R. Kaires, “Expert system algorithms for identifying radiated emission problems in printed circuit boards,” Proc. 2004 IEEE Int. Symp. Electromag. Compat., Santa Clara, CA, Aug. 2004, pp. 57-62.

[8] Y. Fu and T. Hubing, "Analysis Of Radiated Emissions From A Printed Circuit Board Using Expert System Algorithms," IEEE Trans. on Electromagnetic Compatibility, vol. 49, no. 1, Feb. 2007, pp. 68-75