Research On Reliability Of Satellite Laser Communication Terminal In Space Radiation Envirnoment

Satellite laser communication technology has received great attention from all countries due to its excellent communication capability and high confidentiality.With the development of theory and the success of on-orbit testing,the technology is gradually entering commercial applications.Since satellite laser communication terminal equipment is irreparable,it is necessary to study the life and reliability of satellite optical communication terminals under space environment conditions.However,to date,reliability studies for satellite optical communication terminals have not been publicly reported.In this paper,the reliability research of terminal equipment on satellite optical communication is carried out for the first time,and the following work is mainly carried out:1.According to the structure of satellite laser communication terminal and the characteristics of on-orbit operation of satellite optical communication terminal,the reliability model of corresponding mission is established based on the theory of reliability analysis.According To this model,the reliability of the system and components can be simply described through such parameters as reliability,failure efficiency and Mean Time To Fail(MTTF),and the relationship between the reliability of components and the reliability of terminal system can be studied,laying a theoretical foundation for the reliability calculation of terminal.2.In order to study the reliability of each component in the laser communication terminal,the components used in the terminal are classified into three types: optical system components,electrical system components,and mechanical platforms according to their attributes.For each component in each system,the device damage model is established respectively,and the inherent reliability model is studied based on the temperature environment in which the device is located,which provides a data foundation for computing terminal reliability.3.Based on the inherent reliability model of all components and the task reliability model of the terminal,the task reliability function of the terminal system can be studied.According to the task reliability function combined with the reliability theory knowledge,the MTTF of the terminal device can be estimated.In order to solve the problem of low reliability of the terminal system,a redundant design solution is proposed and its improvement efficiency is studied.By extending the research method of this paper,we can study the basic reliability of the terminal,which means that the research method of this paper has universal value.4.Based on the analysis of the working environment of the terminal,the device used in the terminal is analyzed for damage in the space environment.According to the accumulation effect of device damage,the influence of environment on the reliability of terminal components is studied by mathematical methods.It is found through research that a normal distribution cumulative distribution function can be introduced as an environmental impact factor to describe the reduction of device reliability.Device-based environmental degradation and terminal reliability models can be used to study the degradation of end systems in the environment.In this paper,the reliability model of satellite laser communication terminal is established.Based on this,the mission reliability and basic reliability,as well as the impact of space environment on its terminal reliability are studied.It provides reliability technical support for the use of laser communication terminal products,and also provides a theoretical basis for future reliability evaluation of inter-satellite and inter-satellite communication systems.