# Simulation of Achievable Data Rates of Broadband Power Line Communication for Smart Metering
## 8 Measurement in Real Topology--Evaluation of Simulation  
According to topology and cable specification in Figure 9, the measurements were conducted between node n1 (HeadEnd modem located in the transformer substation (TS)) and two measurement points (Smart Meters), no. 26 and no. 32. The distance between TS and point no. 32 was 836 m, and from TS to point no. 26 od it was 705 m.  
The AV200 broadband power line technology with physical layer data rates of 200 Mbps based on the OFDM technology and NB-PLC based on single carrier solution with BPSK modulation were used for measurements. The aims of real measurements were:  
* Verification of the simulation results of BPL, especially these parameters: \[\begin{array}{ll}\odot&\text{Reliability of communication;}\\ \odot&\text{Number of repeaters;}\\ \odot&\text{Communication distances without repeaters.}\end{array}\]
* Comparison of simulation and measurement result of BPL with NB-PLC with single carrier.  
The measurements of BPL were performed via GUI of the HE modem, where the network topology with TDR and CPE were available. The measurements of NB-PLC were performed via GUI of the NB-PLC modems and also with tools for serial communication.  
Table 3 shows the results of the possibility of communication without repeaters for BPL and NB-PLC. Smart Meters no. 32 and no. 26 did not communicate with BPL without repeaters due to long distances and many transitions between underground and overhead power lines. For the distance of 367 m between n20 and n27 it was not possible to establish BPL communication due to distance limitation of this technology. Therefore, for this critical path, an additional repeater was installed in the fuse box in point no. 21.  
To find the reason why point no. 32 did not communicate with NB-PLC, the impedance of the nearest fuse box no. 28 was measured. The connection was not established due to the section of overhead line of 43 m length between fuse boxes no. 28 and Smart Meter no. 32. The impedance of the power line between these fuse boxes was measured and the impedance between these two ends of the line was very different (possible reason for failure of PLC communication in point no. 32 with NB-PLC and also reason for BPL repeater in no. 28).  
Table 4 shows the results of the possibility of communication with repeaters for BPL Smart metering infrastructure. The repeaters are considered in Smart Meters and one additional repeater in the fuse box for point no. 21 (see Figure 9).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Measuring Point** & **Distance from TS [m]** & \multicolumn{2}{c}{**Possibility of Communication**} \\ \cline{3-4}  & & **BPL** & **NB-PLC Single Carrier** \\ \hline Smart Meter & & NO & NO \\ \cline{3-4}   no. 32 & & (long distances, lack of repeaters, transition between underground, and overhead) & (communication in the near fuse box (no. 28) was possible) \\ \cline{3-4}  & & NO & YES \\ \cline{3-4}  & & (long distances, lack of repeaters) & (BPSK, 5 kb/s) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Possibility of BPL and NB-PLC communication—without repeaters.