Introduction of the amplitude probability distribution (APD) measurement in CISPR 32

CISPR 32 emission requirements for multimedia equipment (MME) describes that “The peak detector limits for radiated emissions requirements above 1 GHz shall not be applied to emissions produced by arcs or sparks that are high voltage breakdown events.” In order to verify this exclusion of limits, we investigated impacts of impulsive disturbances from printer on Wi-Fi communications that were generated by feeding papers especially in low humid winter season, concluding no remarkable impact observed. We have therefore extended our investigations to cover most of all wireless communication systems above 1 GHz such as LTE, WCDMA, GSM, DAB and DECT. Measurements have been made of the APD of disturbances and the communication qualities. As a result, it is found that GSM and Wi-Fi have the lowest immunity. Finally we propose addition of the APD limits to CISPR 32 based on the immunity level of GSM and Wi-Fi so as to keep current spectrum protection level. The introduction of the APD measurement and the proposal of the limits in CISPR 32 has currently been discussed in CISPR.