• Influence of frequency-dependent and sub-cycle impedance variations on G3-PLC. • EMC filters imply high signal attenuation in the NB-PLC frequency band (9–500 kHz). • Degradation of the FER-LQI due to sub-cycle impedance variations. • Better performance of G3-PLC in terms of bitrate for a given LQI. The frequency– and time–dependent grid impedance is one of the major factors affecting the performance of Narrowband Power Line Communications (NB–PLC) systems. This paper aims to evaluate the potential impact of impedance variations on NB–PLC according to G3-PLC under laboratory conditions. First, the attenuation suffered by the PLC signal and the communications performance are analyzed in the presence of frequency–dependent impedance variations. According to the results, high attenuation is reported in the propagation channel, but the communications thresholds are not affected by the resulting Channel Frequency Responses (CFRs). Second, the study on the influence of short-term impedance variations concludes that the impedance variations within the fundamental period of the mains signal (20 ms) negatively affect the quality of the communications. Finally, a comparative analysis between G3-PLC and PRIME v1.4 is included, determining that G3-PLC in the FCC band is a better option under the analyzed conditions in terms of the Signal to Noise Ratio (SNR)/Link Quality Indicator (LQI) required for achieving a certain bitrate. This is the first paper that evaluates the performance of G3–PLC in the presence of impedance variations, including a comparison with PRIME v1.4 in terms of SNR/LQI vs bitrate. The findings are of special interest for the industry and the research community, particularly in the design and development of the next generation of PLC transmitters/receivers.
Larrucea et al. (Wed,) studied this question.