EMC (electromagnetic compatibility) testing is a test of the electromagnetic compatibility of the sample. Including measurement equipment, measurement methods, data processing methods and evaluation of measurement results. Measuring equipment and measurement methods, the international community has a common CISPR series of standards to regulate. China has also introduced with the CISPR series of standards and IEC series of standards corresponding to the electromagnetic compatibility testing standards. Among them, such as GB 4343 and other mandatory national standards have been applied in the mandatory testing of product safety.