# Research on Underwater Wireless Optical Communication Channel Model and Its Application
###### Abstract  
Underwater wireless optical communication (UWOC) is an emerging technology with wide-ranging applications in marine exploration, offshore industries, environmental monitoring, and underwater robotics. In order to investigate the application of UWOC in environments of different water quality, this study establishes a model of an optical communication channel and analyzes the impact of water quality on communication range. Our experimental design is employed to validate the effectiveness of the model and analyze the sources of model errors. Furthermore, this research introduces the concept of an \"effective communication space\" for underwater optical wireless communication and constructs an experimental platform to test the effective communication space under various water quality conditions. In addition, the application methods and workflow of wireless optical communication on underwater mobile platforms are discussed, and field tests are conducted in a practical lake environment to verify  
quantifying the light absorption capability of water. Consequently, the correspondence between the attenuation coefficient and transmission range is a crucial under-researched topic in the study of the underwater environments, especially for the application of UWOC technology [5; 6; 7; 8].  
In the evaluation of UWOC technology's communicative reach, contemporary research predominantly centers on the parameter of optical transmission distance. In the practical engineering application of underwater intelligent devices such as autonomous underwater vehicles (AUVs), most communication systems expand their communication emission angle and receiving field of view to rapidly establish underwater transmission links for inter-cluster communication [9; 10; 11]. This expansion increases geometric loss and reduces communication distance. Consequently, reliance solely on the metric of communication distance offers an incomplete portrayal of a system's spatial coverage. In UWOC deployments, the dynamic nature of the communication range and angle gives rise to continuously evolving communication channels. The communication range and angle are interdependent parameters in optical communication systems. It is essential to establish effective coupling between these indicators within a designated operational range to ensure efficient and reliable optical communication. In response to this issue, the current study, in conjunction with engineering applications, proposes the method of using the \"effective communication space\" to evaluate the effective spatial coverage of communication systems.  
Considering the application of optical wireless communication on mobile platforms like AUVs, it is evident that both water quality and effectively coupled space significantly impact the efficacy of communication. Importantly, these coupled effective spaces cannot be directly ascertained by optical communication devices alone. This research thus involved a comprehensive analysis of a model, experimental testing on an UWOC channel, and the exploration of optical wireless communication methods and workflows for underwater mobile platforms. Specifically, the paper is structured as follows. Section 2 provides an analysis of the factors influencing the UOWC channel and the determination of the effective communication space. A detailed description of the experimental setup and the analysis of the results are presented in Section 3. Section 4 presents the practical application process of wireless optical communication on a mobile AUV in water. Our conclusions are drawn in Section 5.