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88 DESIGN007 MAGAZINE I DECEMBER 2018 in the design of the electrical elements. These rules are not obvious from the basic informa- tion given about fractal shapes in the avail- able data; however, it becomes evident in the analysis of test data. This capability indicates that this reduction is useful in many existing products to elimi - nate the need for special requirements or fixes to reduce radiated emissions. Only a simple, no-cost design change is needed to implement this improvement, which will eliminate pro - cessing such as edge plating. Why does the application of fractal technol- ogy design rules have such an effect on cur- rent printed circuit designs? It's very much like understanding why airplanes are better designed with modern aerodynamics than with the original biplane concepts. PCBs are the biplane of the electronics industry, having changed little since the 1950s in their interactive design. These experimen - tal designs demonstrate the ability to improve high-speed operations using the normal rules of electrical engineering with new physics. Eventually, PCBs will have to conform to interactive scientific design rules to use less expensive and more easily manufactured designs or convert to optical technology, which presents a plethora of nightmarish problems. Here is a quick review of some of the testing done thus far, using a test board constructed with a small 0.030" space-filling curve around the perimeter. Adding this type of feature will have virtually no impact on the size or cost of the raw board while changing its electrical response significantly. Figure 5 demonstrates that the electrical response of a PCB component can be altered by simply changing small features on a con - ductive layer that are otherwise unused. This capability may allow the coupon above to operate at a higher frequency with lower radi- ated noise at targeted frequencies. The cost difference in making this change is zero. The value of this technical performance can be decisive. Fractal shapes by their very nature will present a form that has more dissipation of heat than other shapes. In addition, electrical fundamentals—such as impedance, crosstalk, and other features—can be controlled with the symmetry of fractal design. What might these design features be useful for? Currently, 5G technologies featuring 20 gigabit/s at speeds of 15 GHz are not achiev - able with standard PCB technologies and materials. If your plan is to change materials or morph to a different technology like opti- cal circuit boards, the cost difference is astro- nomical. Figure 6: An experimental 0.030" proprietary Hilbert fractal edge pattern.

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