Difference between space and underwater wireless laser communication;
Compared with the development of fixed-line optical communication, underwater wireless optical communication is still progressing slowly, and the technology is far from being practical. The establishment of underwater optical communication network can refer to the optical communication network established and operated on land. China's fixed network is transformed into all-optical network, which further improves the transmission rate, reduces the transmission delay and improves the transmission capacity. Underwater wireless optical communication also has to face and solve the problems of communication speed, communication capacity and communication safety, and still has to solve two eternal themes of communication: transmission and switching. However, compared with the traditional fixed-line optical communication, the development of underwater wireless optical communication is bound to solve more problems. For example, in optical fiber communication, optical fiber is a transmission channel with relatively stable characteristics, and it is easy to establish a mathematical model of the channel. By improving the production process, the loss of optical fiber can be reduced as much as possible, and dispersion fiber (DCF) can be used to compensate the dispersion. However, the complexity of underwater environment, organic and inorganic substances contained in water, aquatic organisms and other environments make it more difficult to establish the mathematical model of underwater optical communication channel than that of optical fiber communication channel.