## 6 Simulation Results and Analysis
### Energy Consumption of Nodes under Different Kinds of Network Partition  
Figure 10 shows the total energy consumption of nodes after a round of data collection under different numbers of sectors. Without loss of generality, the number of annuli is set to 3, that is, \(k=3\). Moreover, according to Equation (21), it is not difficult to know that, to ensure that there is at least one node in each RCCH of the outermost annulus, the network can be divided into eight sectors at most, namely \(n\leq 8\). Obviously, with the increase of the value of \(n\), the total energy consumption of the whole network is decreasing. For example, when \(n=8\), the energy consumption is 17.8% lower than that at \(n=4\). The main reason is that the area of each annulus decreases with the increase of \(n\), which releases the burden of nodes in the RCCH to some extent and decreases their energy consumption. In addition, the distance between the CN and the CH is also shortened when \(n\) is large. Thus, the energy consumption on single-hop transmission is also effectively reduced. Then, we keep the network scale unchanged and analyze the total energy consumption under different kinds of network partition methods. The radius of the circular network is set to 240 m, and the total number of nodes in the network is 500. According to Equations (20) and (21), the network can be divided into five annuli at most in order to ensure that there is at least one node in each RCCH. Thus, we adopt three kinds of division, namely, \(k=3\) and \(n=8\); \(k=4\) and \(n=5\) and \(k=5\) and \(n=4\). Table 5 shows the average number of nodes in each RCCH under these three partition methods as well as the total energy consumption of them in one round of data collection. We can find that the energy consumption is the lowest when \(k=3\) and \(n=8\), which is respectively 75% and 65% of that in other two modes. It further illustrates the conclusion that \"the smaller the annulus-sector is, the lower the total energy consumption will be\". It is worth noting that when the number of annulus-sectors is 20, the energy consumption of the network with \(k=4\) and \(n=5\) is about 0.0916 J lower than that with \(k=5\) and \(n=4\). This is because the area of the innermost RCCH of the former is much larger than that of the latter. Thus, more nodes can participate in data transmission. In addition, the fewer the number of annulus is, the fewer the hops is, that results in lower energy consumption on communication. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameter** & **Symbol** & **Values** \\ \hline Initial Energy of Each Node & \(\epsilon_{0}\) & 4 J \\ Maximal Battery Capacity of Each Node & \(C\) & 4 J \\ Length of Network Radius & \(R\) & 240 m \\ The Amount of Data Collected by a Node during a Round of Data Gathering Time & \(l\) & 1800 bits \\ Energy Consumption of the Sending and Receiving Circuit & \(E_{dac}\) & 50 N/bit \\ Energy Consumption of the Amplifier in Free-Space Model & \(\epsilon_{g}\) & 10 J (b/m\({}^{2}\))\({}^{-1}\) \\ Adjustable parameter & \(\alpha\) & 0.5 \\ Adjustable parameter & \(\beta\) & 0.5 \\ Adjustment coefficient & \(\delta\) & 40 \\ The Initial Energy of WCV at the beginning of Each Recharging & \(B\) & 100 J \\ Energy Consumption of the WCV on Travelling One Meter & \(P_{m}\) & 0.0023 J /m \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Parameter values. Table 6 shows the average energy consumption of nodes in each RCCH during a round of data collection. No matter how many annuli are in the network, the energy consumption of nodes in different RCCHs within the same annulus is approximately equal to each other. This is because the cluster head is periodically selected in AEBDC and it also makes full use of the non-cluster heads with high residual energy and low load to forward data collaboratively. This effectively balances the energy consumption of nodes near the center of each annulus-sector.