Analysis Of The Influence Of Exoteric Factors On Mixing Efficiency Of Space Optical Hybrid

Compared to microwave communication,space laser communication has lightweight and miniaturization,low power consumption,anti-jamming,good confidentiality and other obvious advantages.Coherent optical communication as one of its implementation,can meet the high-rate and long-distance communication needs at the same time,and has been widely studied in recent years.Space optical hybrid as a core element of the coherent receiver,its function is closely related to the communication quality of the whole system.Space optical hybrid is extremely sensitive to the quality of the signal beam that received and the research of the exoteric factors on its mixing efficiency is less,so the research content of this paper has academic research value and of guiding significance.Based on the homodyne coherent optical communication scheme,this paper compared and analyzed the selection and principle of optical phase-locked loop and its hybrid.Analyzed the 90-degree space optical hybrid in theory by using jones matrix,deduced the output mixing light and mixing efficiency formula.In response to the need for achieving high-efficiency mixing,carried out the research on the exoteric factors that affect mixing efficiency which based on this mathematical model,including:light field mode,visual axis shaking,light spot size,quality of wave front,polarization states of signal light and detector type.Established the formula model of mixing efficiency with influencing factor respectively and acquired the relation curve.Proposed an improved scheme to achieve 90-degree space optical mixing through analyzed:using multimode fiber output space optical hybrid instead of the traditional scheme.In order to check the result from analysis,a desktop virtual experimental system was built,and through testing the prototype of the multimode fiber output and single mode fiber output space optical hybrid,verified the superiority of the multimode fiber output space optical hybrid in the insertion loss and anti-jamming capability,it can instead the traditional scheme to solve the problems such as sensitivity to the influence of exoteric factors and large signal energy loss and so on.Problems founded in the experiment:the problem of modular interference exist in multimode fiber output space optical hybrid,made the fluctuations of beam energy,and think that the practical-project implementation needs more research demonstration and feasibility analysis.