Conducted interference immunity test to high-speed power line communication system

In this paper, we measured the immunity characteristics to the conducted interference wave, from the aspect of PHY rate (physical layer date rate) of PLC (power line communication) system, and compared with simulation results by MATLAB/Simulink. When the interference signal is impressed to the OFDM (orthogonal frequency division multiplexing) signal, the PHY rate decrease rapidly below C/I (carrier / interference) = -10 dB and become nearly zero around C/I = -70 dB, and so it turns out that the PLC system with OFDM signal has an good narrowband interference immunity characteristic. Furthermore, it is revealed that the PHY rate (physical layer date rate) of PLC modem can be calculated by MATLAB/Simulink even when the narrowband interference signal is impressed through the power line. In addition, we examined the improving effect of the notch band for the immunity characteristics to the conducted interference wave. As a result, it is revealed that the PHY rate normalized by the maximum value increases by about 20% by inserting the notch when impressing the interference signal in the notch band and C/I is improved by 10~15 dB by inserting the notch.