Protection against Danger and Disturbances of Electromagnetic Origin in Telecommunication Network

Disturbances in telecommunication network and installations can have many causes. One of these is the influence of the electromagnetic fields that are generated in different processes. The generation of such fields and their disturbing effects in telecommunication network was early observed. It was the natural sources of disturbances in telecommunication circuits that were noticed first and foremost the atmospheric discharges. Later another type of natural disturbances was observed and caused by geomagnetic storms. By the increasing number of electricity lines and installations in the vicinity of the telecommunication systems other types of disturbing effects were observed. We got the man made sources of disturbances that were caused by the capasitive, inductive and conductive coupling including direct contact between the electric power and the telecommunication systems. Other types of man made sources of disturbances were radiation from RF-transmitters and emission from different electronic devices. By introducing more sensitive electronic equipment often electric power supplied, the mains power and the telecom network will be more and more "connected" to each other. For these reasons a growing number of environmental parameters have to be taken into account concerning both emission and immunity severities to solve the EMC problems nowadays.