The characterization of hybrid PLC-wireless and PLC channels in the frequency band between 1.7 and 100 MHz for data communication

Abstract

This work outlines initially a methodology to be applied to the characterization of electric power grids for data communication purposes. This methodology englobes all the procedures and required signal processing tools for a reliable estimation of features that allow the suitability of a media for data communication. Next, PLC (power line communication) channel results provided by the use of such methodology in a data set obtained from a measurement campaing in in-home Brazilian places are presented. The analyzed channel features are the average channel gain, the coherence bandwidth, the coherence time, the root mean squared delay spread, the channel capacity and the noise power spectral density by considering the following frequency bands: from 1.7 up to 30 MHz, from 1.7 up to 50 MHz and from 1.7 up to 100 MHz. Comparisons among the results for in-home Brazilian PLC channels with other provided for other countries such as Spain, United States, France and Italy showed that, in general, in-home Brazilian PLC channels present smaller attenuation, are less frequency selective and showed smaller delay spread than these countries. Finally, a new medium to provide data communication is presented and defined as hybrid PLC-wireless, in which PLC and wireless technologies are combined. Such novel communication channel is characterized in in-home Brazilian places and important channel features are estimated and discussed. Though the hybrid PLC-wireless channel has been shown more adverse than the PLC channel, the introduction of mobility is its main advantage, something that is impossible in traditional PLC technologies. Thus, this mobility is an important issue that puts hybrid PLC-wireless technologies in a privileged position among the candidates to form the communication infrastructure for smart grids, or to be used as a too to solve the digital divide problem that is more accentuated in poor and in developing countries.