Abstract

Designing a reliable voice transmission system is not a trivial task. Wired media, thanks to their resistance to mechanical damage, seem an ideal solution. The BPL-PLC (Broadband over Power Line – Power Line Communication) cable is resilient to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency situation, including paramedic rescue operations. These features make it an ideal solution for delivering data, e.g. in an underground mine environment. This paper describes a subjective quality evaluation of such a system. The solution was designed and tested in real-time operating conditions. It involved two types of coupling, namely: induction-inductive and capacitive-inductive, as well as two transmission modes (Mode 1 and Mode 11 operating in the 2–7.5 MHz frequency range). The tested one-way transmission system was designed to deliver clear and easily understandable voice messages. The study involved signal samples in three languages: English (both British and American dialects), German, and Polish, processed in three bitrates: 8, 16, and 24 kbit/s, with the Ogg Vorbis codec. Obtained results confirmed the usefulness of the BPL-PLC technology for voice communication purposes. Results of this study may be of interest to professionals from the mining and oil industry.

Citations

Authors (7)