Subjective Quality Evaluation of Underground BPL-PLC Voice Communication System

BPL-PLC Voice Communication System for the Oil and Mining Industry

“…This work is an extended version and a direct continuation of our published conference paper [21]. It summarizes many years of research conducted by the authors, hence some of the results were published early [9][10][11]21]. The content of Section 3, as well as Sections 4.1 and 4.3, has not been previously published.…”

“…As a result, the investment costs of the installation are significantly reduced and operator fees can be omitted. However, the disadvantages of PLC transmission include, most of all, the impact of environmental electromagnetic compatibility (EMC) disturbances, both conducted and induced, on the scope and quality of transmission [7][8][9][10][11]. In addition, PLC transmission should not interfere with the basic functions of electricity networks, such as transmission and distribution of electricity itself.…”

“…This is much faster than narrowband communication. The BPL-PLC technology can be successfully used both for control and monitoring of environmental conditions, and secondary as voice and/or image transmission of the so-called last chance, especially during mine disaster or other random events [9][10][11]. The underground cable lines are above all the most resistant to mechanical damage and thus can provide an effective transmission channel under various hazardous situations.…”

“…Therefore, it may be sometimes difficult to derive the physical quantities of the analyzed cable. Due to this, the verification of the propagation model becomes a major issue to overcome [9][10][11]. Based on previous research conducted by the authors, it has been shown that the efficiency of high-frequency transmission in underground cable mine networks can be subjected to significant changes, depending on the network load conditions (with or without supply, under-voltage but unloaded, loaded, etc.…”