Research On The Power Conversion Technology And The Analog Optical Amplification Technology Of Underwater Relay System

With the development of ocean science and technology and the promotion of ocean strategy,the demand for the construction of the seafloor observatory network and the fiber optic hydrophone system is getting higher.The scale of the seafloor observatory network is also expanding.The optical transmission technology including underwater junction and underwater relay is the key technology of seafloor observatory network,which directly determines the system's extension distance and detection range.Especially in the fiber optic hydrophone detection system,the introduction of the low noise relay amplification directly extends the hydrophone to the farther distance to realize the long distance detection.Therefore,it is significant to improve the performance of the underwater relay system to improve the performance of the seafloor observatory network and the fiber optic hydrophone detection system.According to the demand of long-distance transmission of fiber optic hydrophone system,this paper makes an in-depth research on the analog signal of underwater relay system from the power conversion and low noise erbium-doped fiber amplifier.The main work and innovation points are as follows:1.According to the system structure of the underwater relay system,we analyzed the key technologies of the underwater relay system.This paper is mainly focused on the power conversion technology and erbium doped fiber amplifier technology.2.Making a research on the electric power transmission system and testing the conversion efficiency and the electrical parameters of the electric energy conversion module in the underwater repeater.3.According to requirements of analog optical signal amplification in the optical fiber hydrophone system,the amplification characteristics of the erbium doped fiber amplifier in analog optical system are studied experimentally.4.Set up an underwater relay system for long distance fiber optic hydrophone system,analyze the effect of intensity noise in the amplifier on phase noise and test the noise characteristics of the system.The experimental results show that the power conversion will not introduce extra noise,and the noise level of the doped fiber amplifier is-95 dB,which can meet the requirement of the system application.