Radiated emission characteristics of communication systems using unscreened cables

Various new cable communication systems are being developed which use existing cable infrastructure. These include power line telecommunication (PLT) using low voltage electricity distribution networks (LVEDN), digital subscriber line (xDSL) using existing copper telephony pairs and home networks using domestic mains electricity wiring or indoor telephone wiring. The EMC implications of such systems are examined, with emphasis on proposed PLT systems which would use frequencies up to 5 MHz or more. The radiation characteristics of various configurations of mains power and extension telephone cable networks are presented. Injected signal levels are then related to radiated field strengths at various frequencies and distances. The need for protection of various LF/MF/HF radio services from interference is also considered