Expert System To Address Problems Of Electromagnetic Interference

The three-year project, now in its second year, will result in "expert"software products that will help electronics makers meet federal standardson electromagnetic emissions. The expert system should also save circuitboard makers a lot of time and money by allowing them to catch and fixproblems before the circuit boards are manufactured.

"Computer systems are getting faster and faster, and the faster they get,the more likely they are to act as tiny radios and emit signals," says Dr.Todd Hubing, an associate professor of electrical engineering at UMR. "Whatwe have to do is make them extremely inefficient radiators."

Hubing is one of four UMR electrical engineering researchers involved inthe UMR EMI Expert System Consortium. EMI stands for electromagneticinterference.

The UMR research team also includes one visiting scholar, 15 graduatestudents and five undergraduate students.

The consortium is a three-year project between UMR and nine diversebusinesses -- from equipment manufacturer Caterpillar to computer giantsIntel and Sun Microsystems. The consortium's goal is to develop software toeliminate electromagnetic interference problems during the design phase ofcomputer circuit boards. The project has more than $1 million in fundingfrom consortium members.

In the personal computer's early days, the circuit boards that ran the PCsoften would interfere with the music of an office radio. That's because thecircuit boards act as miniature radio stations and broadcast signals. Theresult is radio static.

This is one common example of how electronic noise can disrupt theoperation of everyday products, and this problem, for the most part, hasbeen taken care of by manufacturers of both PCs and radios. But newproblems of electromagnetic interference are likely to arise as portableelectronic products -- such as compact-disc players, laptop computers andhand-held computers -- become more commonplace. Signals from these gadgetscould potentially wreak havoc on the computer systems of airplanes,automobiles and other complex electronic systems.

At UMR, the researchers test a variety of products in its ElectromagneticCompatibility (EMC) Laboratory, analyze the results, and write thealgorithms that will be used to develop an expert software system that canbe used by any circuit board designer. The UMR researchers then hand offtheir algorithms to the consortium's software partners. Those partners, inturn, develop computer-assisted design software products to be used bycircuit board designers in the industry. All information is shared amongthe consortium's members, and all hardware companies in the consortiumreceive free evaluation copies of the early versions of the software.

When completed, these expert systems will diagnose circuit board designs,catch any potential problems, predict the extent of those problems, andrecommend ways for designers to fix them.

"Through this consortium, we're developing software that does the samething that an EMC engineer would do, looking at things the way a humanwould," Hubing says.

The need for an expert system is great because circuit board designersoften know little about EMI concerns, Hubing says. There are few EMIengineers in the world, but many circuit board designers, he adds.

"If you had a human EMC expert looking over the shoulder of circuit boarddesigners, then you wouldn't have a problem," Hubing says. "But circuitboard designers have a lot of other things to concern themselves withbesides EMI problems.

"As a circuit board designer, you've got thermal considerations, EMIconsiderations, cost trade-offs and manufacturing considerations to takeinto account-- plus you must keep up with the latest in digital technology," Hubingadds. "Circuit designers can't be experts in all of these areas, and sothey're having to rely on tools to catch certain things automatically."

Already, the UMR EMI Expert System Consortium has developed prototypesoftware that all partners in the consortium are evaluating.

Hubing and his colleagues in UMR's electrical engineering department --Drs. Tom Van Doren, James L. Drewniak and Richard E. DuBroff -- first gotthe idea for developing an expert system after working with Boeing on asimilar project. With Boeing, the UMR researchers developed software tolocate EMI "design rule violations" in circuit board designs. The expertsystem software now under development not only locates potential problems,but also analyzes them and proposes specific solutions.

Working with the four UMR professors is Dr. Sergiu Radu, a visitingprofessor from Romania.