# Influence of Random Modulated Power Converter on G3 Power Line Communication
## 6 Conclusions  
In this paper, the coexistence between power and data lines in G3-PLC systems in the presence of randomly modulated power converters has been investigated. More specifically, among the available RPWM schemes, this work focused on RPPM. The effects of different parameters of an RPW-scheme driving power converter (switching frequency, modulation index, and RNUR) on the G3-PLC are assessed by experiments. Communication performance is evaluated in terms of FER, Channel Capacity, and Channel Capacity Loss. The obtained results have confirmed that switching frequencies close to the bandwidth of the G3-PLC causes interference in the PLC system more than those out of the frequency bandwidth. The comparison versus similar results obtained by considering other RPWM techniques has showed that there is a trade-off between CE reduction and coexistence with communication systems. Namely, even if RPPM is not as effective as other schemes (as, for instance, RFM) in reducing the CE exiting the converter, this modulation scheme outperforms RFM in terms of coexistence with communication systems. Moreover, the effects of other RPWM parameters, such as the RNUR and the modulation index, on the PLC system have been experimentally examined to draw general conclusions on the effectiveness of RPWM in assuring coexistence. Results showed that the RNUR and the modulation index of RPPM have a direct effect on the communication channel. Indeed, the performance of the G3-PLC degrades with the increase in the RNUR and the modulation index. However, this is true only when the switching frequency of the randomly modulated converter overlaps with the bandwidth of the G3-PLC. Otherwise the effect is almost negligible.  
Figure 15: FER of the G3 PLC measured with different values of the RNUR and the modulation index of the RPPM modulated DC-DC converter at 100 kHz switching frequency.  
Based on the experimental analysis, it is possible to draw two main conclusions. First, a randomly modulated power converter may deteriorate PLC performance when the converter switching frequency is near the bandwidth of the communication channel. The interference can be avoided or reduced to a minimum by choosing different/non overlapping frequency bands for the converters and/or the PLC systems. Another conclusion is that, among the available RPWM schemes, RPPM is less detrimental than RFM. Obviously, RFM may also result in less interference to the PLC if a lower modulation index is chosen, but with compromising CE reduction.  
Conceptualization, A.H.B., W.E.S., F.G. and P.S.C.; methodology, A.H.B., F.G., P.S.C. and W.E.S.; validation, A.H.B., W.E.S., L.W., F.G., P.S.C., A.M., X.L. and X.W.; formal analysis, A.H.B., W.E.S., L.W., F.G., P.S.C., X.L. and X.W.; investigation, A.H.B., W.E.S., F.G. and P.S.C.; resources, F.G., R.S. and S.A.P.; data curation, A.H.B. and W.E.S.; writing--original draft preparation, A.H.B. and F.G.; writing--review and editing, A.H.B., W.E.S., L.W., F.G., P.S.C., A.M., X.L., X.W., R.S. and S.A.P.; visualization, F.G., W.E.S. and P.S.C.; supervision, F.G., P.S.C., R.S. and S.A.P.; project administration, F.G.; funding acquisition, F.G. All authors have read and agreed to the published version of the manuscript.  
This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 812753.  
Not applicable.  
The authors declare no conflict of interest.