# Wake-Up Receiver-Based Routing for Clustered Multihop Wireless Sensor Networks
## 5 Experimental Setup and Measurement
### Performance Evaluation
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Relay**} & **Proposed Approach CWM** & **SBS** & **NTN** \\  & **mAs** & **mAs** & **mAs** \\ \hline Sink & 1.74 & 2.55 & 2.57 \\ Fog Node & 2.26 & 3.16 & 3.22 \\ Relay 1 & 1.05 & 2.04 & 0.45 \\ Relay 2 & 0.82 & 1.33 & 0.66 \\ Relay 3 & 0.52 & 0.80 & 0.68 \\ Destination & 0.22 & 0.23 & 0.44 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Single nodes energy consumption using 3 Relays. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Relay**} & **Proposed Approach CWM** & **SBS** & **NTN** \\  & **mAs** & **mAs** & **mAs** \\ \hline Sink & 130.46 & 183.55 & 184.34 \\ Fog Node & 137.06 & 189.04 & 193.35 \\ Relay 1 & 84.60 & 129.27 & 47.52 \\ Relay 2 & 55.12 & 78.58 & 75.77 \\ Destination & 30.52 & 28.81 & 57.66 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Nodes time in active mode using 2 Relays. Figure 17 and the corresponding Table 8 present, respectively, the overall consumed energy with respect to number of cluster nodes used as relays. The different strategies \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Relay** & **Proposed Approach CWM** & **SBS** & **NTN** \\  & **ms** & **ms** & **ms** \\ \hline Sink & 154.80 & 233.50 & 235.43 \\ Fog Node & 164.41 & 242.13 & 239.38 \\ Relay 1 & 108.69 & 180.12 & 47.41 \\ Relay 2 & 83.81 & 128.30 & 74.37 \\ Relay 3 & 59.85 & 78.69 & 74.37 \\ Destination & 30.62 & 28.77 & 56.04 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Single nodes time in active mode using 3 Relays. Figure 16: Measured time of every single node in active mode using 3 Relays. based on the number of relays used for data transmission were considered to understand how the energy consumption changes when the communication path is extended. The results show that the benefit regarding the energy consumption is given since our approach consumes less energy than the other compared protocols in all network sizes. The reason for this is that although the sensor nodes used for data transmission are all woken up at the same time, the Fog Node has only to send one single WuPt. The unique sending and simultaneous waking up of the cluster nodes leads to all of the used nodes being in active mode and ready to react immediately. Compared to SBS, which enables sequential transmission of WuPts, the longer activity state in the active mode of the relays, as well as the multiple transmission of WuPts, results in increased energy consumption. The approach followed in NTN, in which the destination node is woken up directly, also presents increased energy consumption. This is due to the fact that each of the relays has to send WuPt in addition to the actual data packet. This increased sending of packets leads to a non-negligible energy consumption. Regarding all three strategies, we can clearly see the superiority of our approach in terms of energy-efficiency. Regardless of the number of relays, our approach delivers the best result in all measurements. Figure 18 depicts the performance of the different strategies in terms of packet transmission delay with respect to the different number of relays participating in the transmission  
Figure 17: Nodes of energy consumption related to the number of relay nodes comparing the 3 strategies. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Relay**} & **Proposed Approach CWM** & **SBS** & **NTN** \\  & **mAs** & **mAs** & **mAs** \\ \hline
1 Relay & 3.51 & 4.45 & 4.42 \\
2 Relays & 4.77 & 6.82 & 6.15 \\
3 Relays & 6.59 & 10.10 & 8.03 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Nodes of energy consumption related to the number of relay nodes comparing the 3 strategies. route. The specific results can be found in Table 9. As shown in this figure, our approach drastically outperforms both of the other strategies in shorter communication delay, and the more the number of relay nodes increases, the more the out-performance of our proposed approach becomes clearer.