Personal communication on residential power lines-assessment of channel parameters

A possible concept of voice communication using a residential distribution power line for the access network is investigated with special reference to its application in the underprovided regions of developing countries. Usually such a distribution grid connects up to 100 houses served by one transformer unit and spreads out up to 1 km. Acceptable grade of service (GOS) requires a capacity of 10 channels and reliable random access scheme. The survey of literature shows that precise channel parameters are not known, as noise, attenuation and impedance change with frequency, distance, time and location (network topology and point of connection). The efforts to date have mostly concentrated on systems or modems design for data rather than voice communication. Aided by statistical processing of the measurement data one should be able to create a "more stable", usable analytical model of the channel, on which the authors are currently working. Meanwhile several channel refinements (noise filtering, impedance stabilization and line coupling) introduced to overcome its critical impairments are suggested in this paper.