# Research on Networking Protocols for Large-Scale Mobile Ultraviolet Communication Networks
###### Abstract  
Ultraviolet (UV) communication, characterized by non-line-of-sight (NLOS) scattering, holds substantial potential for enabling communication networking in unmanned aerial vehicle (UAV) formations within strong electromagnetic interference environments. This paper proposes a networking protocol for large-scale mobile ultraviolet communication networks (LSM-UVCN). In large-scale networks, the proposed protocol establishes multiple non-interfering transmission paths based on a connection matrix simultaneously, ensuring reliable space division multiplexing (SDM) and optimizing the utilization of network channel resources. To address frequent network topology changes in mobile scenarios, the protocol employs periodic maintenance of the connection matrix, significantly reducing the adverse impacts of node mobility on network performance. Simulation results demonstrate that the proposed protocol achieves superior performance in large-scale mobile UV communication networks. By dynamically adjusting the connection matrix update frequency, it adapts to varying node mobility intensities, effectively minimizing control overhead and data loss rates while enhancing network throughput. This work underscores the protocol's adaptability to dynamic network environments, providing a robust solution for high-reliability communication requirements in complex electromagnetic scenarios, particularly for UAV swarm applications. The integration of SDM and adaptive matrix maintenance highlights its scalability and efficiency, positioning it as a viable technology for next-generation wireless communication systems in challenging operational conditions. 26 May 202  
Mbps [1; 2; 3; 4; 5; 6; 7]. Combining UV communication with self-organizing networks and constructing UV self-organizing networks can effectively overcome this problem. In recent years, swarm drones have developed rapidly in military, civil, and other applications. With the characteristics of NLOS communication, high confidentiality, and strong anti-interference ability, UV communication has great development potential in solving communication problems of drone swarms in strong electromagnetic interference environments. In the application of drone group networking, traditional radio frequency communication can easily ensure that any two nodes in the network can directly communicate without relaying or through one or two relays by taking advantage of its communication rate and distance, and improve the network performance through complex protocols. However, when applied to the same scenarios, due to the limitations of communication rate and distance, UV communication networks have to adopt networking protocols with lower complexity. Moreover, communication between nodes may rely on more relays, which not only leads to a decrease in throughput but also increases the probability of data interference during the transmission process. This poses more stringent requirements for the networking protocols applied to UV communication networks. Refs. [8; 9] have designed a directional MAC protocol for flight formations. This protocol can enhance network throughput and reduce latency through means such as channel reservation. However, this protocol is designed for large platforms. Without the constraints of energy supply and load, the communication distance and rate can be significantly increased by adding light sources, boosting optical power, and other measures, so it is not applicable to small and micro platforms like drones. Refs. [10; 11] have proposed clustering-based UV communication network protocols. In the proposed protocols, nodes with a large spacing are divided into different clusters. The cluster heads are responsible for the management of nodes within the clusters and the allocation of channels, thereby achieving spatial division multiplexing among different clusters.