## 4 The Design of Routing Protocol
### Data Packet Forwarding
Hence, the unnecessary energy consumption caused by data diffusion or dispersion in multiple directions is mitigated. In particular, in a dense network scenario, the pipeline radius is reduced to decrease the energy consumption while achieving the desired PDR. The incorporation of the SVM model in the ASVMR protocol facilitates the selection of sensor nodes with higher remaining energy. This contributes to a more balanced distribution of data traffic and prevents premature node failures caused by excessive energy consumption. Moreover, the ASVMR protocol employs the SVM model to determine the minimum hop count, which reduces the end-to-end delay and energy consumption. Second, the impact of node mobility on the performance of five routing protocols is simulated and compared. Figure 9 shows the impact of node mobility on the performance of five routing protocols, where the number of sensor nodes is set as 150; the node moving velocity changes from 0 m/s to 2 m/s; the discount factor is set as 0.8; and the routing pipe radius is set as \(R\). The PDR, the hop count, the end-to-end delay, and the energy tax are shown in Figure 9a-d, respectively. From Figure 9a, we observe that as the node moving velocity increases, the PDR of the five routing protocols increases slightly. Therefore, in a sparse network, the mobility of the sensor nodes has only a slight influence on the PDR. This phenomenon occurs because the network topology changes rapidly when the node velocity increases, resulting in a rapid coverage of the void region. However, as the network becomes denser, the emergence of void regions decreases. From Figure 9b, one finds that as the node moving velocity increases, the hop count of the five routing protocols changes slightly. Therefore, the moving velocity of the sensor nodes has a negligible influence on the hop count. Figure 8: Impact of the node density on the performance. From Figure 9c,d, we observe a slight decrease in the end-to-end delay and the energy consumption of the five routing protocols as the node moving velocity increases. This is because the node mobility can improve network coverage, which slightly enhances the data packet transmission efficiency in the network. Therefore, these five routing protocols demonstrate effective handling of sensor node mobility. Moreover, through comparison, the performance of the proposed ASVMR protocol is the best, and the proposed ASVMR protocol is a suitable choice for a mobile UASN. ### Impact of Parameter

First, the impact of the discount factor on the performance of the proposed ASVMR protocol is simulated. Figure 10 shows the impact of the discount factor on the performance of the proposed ASVMR protocol, where the number of sensor nodes is set as 150; the moving velocity of the sensor nodes is set as 0; the discount factor changes from 0.1 to 1; and the routing pipe radius is set as \(R\). The PDR, the hop count, the end-to-end delay, and the energy tax are shown in Figure 10a-d, respectively. From Figure 10, we observe that the magnitude of the discount factor has a certain effect on the performance of the ASVMR protocol. As the value of the discount factor increases, the PDR increases, while the hop count, the end-to-end delay, and the energy consumption decrease. It is demonstrated in (18) that the discount factor magnitude determines the proportion of the future one-hop decision value to the total decision value in routing decisions. A larger value of \(\gamma\) indicates a greater proportion of the one-hop decision value, which results in a better performance of the ASVMR protocol initially. This is because considering the future one-hop decision value in the routing decision makes the decision closer to the global optimal routing than just considering the current decision value. Figure 9: Impact of the node mobility on the performance. However, as \(\gamma\) further increases, the advantage becomes less apparent because the current state also affects the routing decision.