WIDE-BAND IMPULSIVE NOISE SURVEY OF THE ACCESS NETWORK

There is currently much interest in higher rate digital transmission in the access network as a bridge to the eventual deployment of optical fibre, but the usefulness of such systems may ultimately be limited by impulsive noise. An extensive survey of impulsive noise in the UK access network is reported in which wide bandwidth digital recording is being used with simultaneous recording of both the differential and common-mode components. These features make this survey useful for the purposes of transmission system design, especially when combined with analysis techniques which yield pertinent statistics. A description of the collection and analysis process is given as well as the statistics of the results gathered so far It has been found that the peak level of impulsive noise experienced by an access network transmission system is generally an increasing function of the system signalling rate. The balance about earth of the impulsive noise has been found to be good even at the higher frequencies.