Development on ISN and CDN for EMC Measurement at Telecommunication Ports

The widespread application of digital LSIs and microprocessors technologies to telecommunications equipment has resulted in a large increase in electromagnetic interference as well as a deterioration in noise-immunity. This has created a need to develop the measurement methods of disturbance and immunity at telecommunication ports. CISPR and IEC have been discussing the measurement methods. An impedance stabilization network (ISN) and a coupling and decoupling network (CDN) have been developed for the measurement of disturbance and immunity. This paper presents the ISN and CDN which are recently developed in Japan and shows that the ISN and CDN meet the requirements proposed by CISPR and IEC.