Automatic PCB-EMI evaluation system with high-efficiency image mapping method

This paper presents an automatic PCB-EMI evaluation system with a high-efficiency image mapping method. The method combines image positioning technique with near-field electromagnetic interference (EMI) evaluation technique, which could automatically obtain the tested board's near-field spectrum amplitude and then maps the board's image with high efficiency. After processed by computer, each frequency's near-field distributions corresponding to each part of the circuit board could be vividly displayed in rainbow map. Thus, positions in this map of serious EMI could be immediately determined. Validity of the proposed system is proved by testing a commercial embedded microcomputer development board. The proposed system could conveniently produce PCB-EMI map with extremely little time and low cost consumed, which drastically benefits the designers to solve the intractable EMI suppression issue.