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The aim of this paper is to develop a complete model of a power-line communication (PLC) system operating on a medium-voltage (MV) network. The core-shield configuration was chosen for signal transmission in the power cables. In order to validate the developed model experimental, the medium-voltage network of the Favignana island was used to carry out detailed testing. The transmission was performed between two transformer substations in the presence of mains voltage (i.e., 24 kV). ST7540 FSK power-line transceivers, together with capacitive coupling interfaces, were used for the transmission and the reception of the communication signal. The correlation between the experimental measurements and the simulation results would appear to validate the use of the developed model for the analysis of MV transmission channels.

This paper describes carrier gain adjustment (CGA) in the CENELEC A-band, a counter-measure against the negative impact of a transmitter coupling circuit's filter characteristic in this band. As the CENELEC A-band lies very close to the power waveform frequency, a steep -40 dB/decade coupler filtering slope is present in the lower parts of this band. Therefore, different symbol carriers (of different frequencies) are exposed to different attenuation factors. With linear amplification, only the least attenuated carrier can be amplified to the maximum level allowed by regulations, whilst the other carriers will be transmitted below the maximum level. Conversely, all carriers are exposed to similar noise levels, present on the power-line. CGA however, counters the unequal attenuation effect of the transmitter coupling circuit, by amplifying all carriers to an equal, maximum amplitude. As carrier gain adjustment is directly linked to the frequency response of the transmitter coupling circuit, this coupler needs to be characterized before implementing CGA. As measuring rod for this study, the performance of orthogonal M-ary frequency shift keying without coding, in the presence of white noise, is used. Results show that under the above conditions, carrier gain adjustment proves successful in equalizing the attenuating effect of the transmitter coupling circuit, thereby improving overall performance.

This paper investigates the multiple emitting multiple receiving points diversity technique as one of the ways of meeting the tripartite conditions of high data rate, less transmit power, and low unwanted electromagnetic radiations of the frequency-selective power-line channels. To be resilient to the intersymbol interference present in frequency-selective fading, the diversity technique must be used in conjunction with wideband multicarrier modulation. We propose an efficient space-frequency and space-time-frequency (STF)-coded multitone M-ary multilevel frequency-shift keying (M3FSK) for high-rate indoor communications over the multiwire power-line channels. We show that coding by using three dimensions of space, frequency, and time, the STF system is capable of achieving up to 8-dB diversity gain. Simulation results are provided to demonstrate the performance improvement of the STF over other diversity schemes as well as over single-wire M3FSK systems in a highly impulsive power line.

Power line communication (PLC) is a communications method where signals are carried across already existing power lines, rather than through other mediums such as optical fibers or radio waves. PLC has been a very important interdiscipline topic for power, communications, industrial, and automation engineers and researchers since the 1980s. Designing and planning optimized or standard PLC systems require information and data regarding signal attenuations, load variations, and communication performance for various locations of the world which have different power networks. In this study, PLC system is modeled by ABCD matrix and simulated via electronics workbench. In order to obtain data from Turkey's power lines, signal measurements at the frequencies of 50-200 kHz are carried out. The effects of load, frequency, line length, and the distribution transformers are examined. The properties of home appliances used in an average Turkish household are experimentally determined. System performance in terms of the bit error probability are calculated for FSK modulation.