## 5 Experiments  
### Experimental Setup  
This paper utilizes NS-3 (Network Simulation Version 3) network simulation software to simulate data transmission among nodes in an unmanned cluster network. Compared with other network simulation tools, such as NS-2, OMNeT++, and Simulink, NS-3 as an open-source simulation platform based on C++ and has significant advantages. First, NS-3 comes with a comprehensive protocol stack that supports a wide range of common network protocols, including TCP, UDP, Wi-Fi, LTE, and 5G, making it highly adaptable to various network scenarios and simulation requirements. Additionally, users have the flexibility to access, modify, and extend the source code within NS-3, enabling the creation  
Figure 7: Route reply process of AODV-EM protocol.  
of customized network protocols and simulation modules, thus offering greater flexibility and support for researchers. More importantly, NS-3 is capable of large-scale network simulations, supporting the modeling of network environments with hundreds or even thousands of nodes. When simulating large-scale unmanned cluster networks, NS-3 can efficiently manage simulation resources, optimize simulation strategies, and ensure both the efficiency and accuracy of the simulation process [40; 41].  
In the virtual network simulated by NS-3, elements such as nodes, links, protocol stacks, and other elements in the network topology are abstracted as various C++ classes, and their connection operations are abstracted into associations among different C++ objects through function calls. For example, network nodes are represented by the Node class, and each simulated node requires the installation of NetDevice, Channel, Protocol Stack, Packets, Application, and other elements to achieve normal communication functions. This object-oriented design approach allows users the flexibility to construct and customize the desired network topology and behavior.  
In addition, NS-3 software also provides users with powerful tool support. In this software, the FlowMonitor module can be utilized to monitor the transmission status of various data streams in the network and collect performance indicators such as transmission rate and packet loss rate. Furthermore, it also supports visualization tools such as NetAnim and PyViz, which allow for the visualization of network topology, node movements and communication status, thereby facilitating a more intuitive observation of network behavior during simulations.  
In order to verify the performance improvement of the AODV-EM protocol proposed in this paper compared with the traditional AODV protocol in unmanned cluster network applications, NS-3 software is used to build a 1 km \(\times\) 1 km simulation scenario, in which 50-140 UAV nodes are deployed, and each node moves irregularly within a speed range of 5-50 m/s. As shown in Figure 8, the red dots represent the UAV nodes, and the green lines represent the network links formed between the nodes, through which the specified data can be transmitted. The detailed simulation parameters of NS3 software configured in this paper are shown in Table 1.  
Figure 8: Simulation scenario built by NS-3 software.