# Performance Comparisons of Broadband Power Line Communication Technologies
## 3 Bit Rate and Power Spectrum Comparisons
For EDV and DV modes, 40 information bytes and 12 bytes are transmitted by 16 OFDM symbols, respectively. Using the values in Tables 1 and 2, the transmission rates are obtained by Equation (2). The transmission rates for HS PLC are shown in Table 4. The transmission rate for NORMAL mode, 25.684 Mbps, is the maximum rate, when assuming that D8 PSK is used for each subcarrier, and the rate 3/4 CC is employed for the FEC. When the rate 1/2 CC is used for the FEC, the transmission rate decreases to 17.123 Mbps. For the modes of DV and EDV, the values are the actual transmission rates of the physical layer. These transmission rates for HS PLC are also shown in Figure 9.  
There are several methods to numerically estimate the power spectrum or power spectral density, such as periodograms and [PERSON]'s method. [PERSON]'s method is known to reduce the noise in the \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**HPGP**} & \multicolumn{3}{c}{**HS PLC**} \\ \hline
**Mode** & **STD** & **HS** & **MINI** & **NORMAL** & **EDV** & **DV** \\ \hline Rate & 4.707 (4.923) & 8.942 (9.845) & 3.737 (3.772) & \(\leq\)25.684 & 1.603 & 0.481 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Transmission rate for HPGP and HS PLC (Mbps). \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \(DV_{n}\) & **1** & **2** & **3** & **4** & **5** & **6** & **7** & **8** \\ \hline Rate, \(N_{bpt}=2\) & 12.784 & 6.392 & 4.649 & 3.409 & 2.841 & 2.324 & 1.967 & 1.763 \\ Rate, \(N_{bpt}=4\) & 25.568 & 12.784 & 8.523 & 6.392 & 5.682 & 4.649 & 3.934 & 3.409 \\ \hline \hline \(DV_{n}\) & **9** & **10** & **11** & **12** & **13** & **14** & **15** & **Mini DF** \\ \hline Rate, \(N_{bpt}=2\) & 1.550 & 1.421 & 1.278 & 1.162 & 1.065 & 1.003 & 0.930 & 0.852 \\ Rate, \(N_{bpt}=4\) & 3.008 & 2.841 & 2.557 & 2.324 & 2.131 & 1.967 & 1.826 & - \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Transmission rate for IoT PLC (Mbps). Figure 9: Transmission rate of IoT PLC according to diversity numbers. estimated power spectra which is noticeable in a periodogram [33]. We estimate the power spectrum of the transmitted PLC signals by [PERSON]'s method. The number of samples used to obtain the spectrum is about 1 million. Figure 10a shows the power spectrum of the IoT PLC signal. The horizontal axis ranges from 0 to half of the sampling frequency. The signal is designed to occupy the frequency band of 2-28 MHz. However, in the band, there are forbidden ranges due to the use of wireless communication such as short-wave radio and amateur radio. As in other countries around the world, the radiation levels for each frequency band are strictly regulated by law in Korea. In Figure 10a, the notches are located in the forbidden bands and are very deep. The power at band edges is about 70 dB lower. Figure 10b,c shows the spectrum results for HPGP and HS PLC, respectively. The frequency range is from 0 to \(f_{s}/2\), which corresponds to 37.5 and 25 MHz for HPGP and HS PLC, respectively. The frequency bands for HPGP and HS PLC are 2-28 and 4-24 MHz, respectively. In the computer experiment, the subcarrier masks in the standards [6; 7; 9] are applied, and the power of the transmitted signals for the three PLC technologies is made to be equal. Since the bandwidth of HS PLC is narrower than the others, the power spectrum level is higher. The spectrum notches in HS PLC is very shallow compared to those of the others. The notches are only about 20-25 dB deep because the RI value of HS PLC is short. Since the power at the band edges is observed only about 30 dB lower, an additional analog filter is needed to control the sidelobe power. In HPGP, the notch depth is about 30-40 dB and the power at band edges is about 40 dB lower. Thus, HPGP has better power spectrum properties than HS PLC in terms of the notch depth and out-of-band power. IoT PLC has better spectral properties than HPGP since IoT PLC has deeper notches and lower out-of-band power than HPGP. Figure 10: Power spectrum: (**a**) IoT PLC; (**b**) HPGP; and (**c**) HS PLC.