Radiated Emissions From High Frequency Powerline Telecommunications (PLT) Systems

Summers, Iain (2011). Radiated Emissions From High Frequency Powerline Telecommunications (PLT) Systems. PhD thesis The Open University.

DOI: https://doi.org/10.21954/ou.ro.0000f1cb

Abstract

The use of broadband Powerline Telecommunications (PLT) to deliver high speed services has been anticipated since the late 1990s. Due to its radiated emissions in the High Frequency (HF) band, the regulatory authorities have had difficulty in defining a repeatable measurement technique and an acceptable radiated limit for Electromagnetic Compatibility (EMC) compliance. Other researchers have undertaken work to predict, model or measure the effects on victim receivers but the uncertainty of the measurements is rarely discussed.

This thesis identifies the areas of uncertainty in PLT radiated emission measurements and recommends a method to account for the measurement errors. A measurement campaign was undertaken in urban, rural and semi-rural test sites in the UK to demonstrate the effects of antenna type, orientation and measurement distance. Furthermore for each measurement location, attenuation with distance properties are described which can be used in the prediction of PLT radiated emissions at a distance. Additionally the K-factor which had previously been thought to be a useful parameter is calculated at each location and is shown to be of little value in the determination of a “safe radiated emission limit” for PLT.

A novel test method of mutual interference testing is described which provides a more realistic demonstration of the effects of PLT radiated emissions on HF receivers. In conjunction with a risk mitigation strategy a compromise radiated emission limit is recommended that may facilitate the regulation of PLT.