Reseach Of Novel Tunable OADM Based On Fiber Grating And Mach-zehnder Interferometer

All-optical communication network has developed recently with the demand of large-bandwidth communication network,which also provides a way to keep on track with the development of various emerging business.Particularly,Optical Add-Drop Multiplexer(OADM)has received the widespread attention as a indispensable unit of all-optical communication network.At present,many kinds of OADM structure has been put forward,while OADM based on fiber grating has the advantages of simple structure,high isolation,low loss,easy to be coupled with other optical devices,unfolding the unique advantages of the whole fiber structure,these advantages make it more excellent than other types of OADM.In this paper,experimental research object is mainly focusing on the tunable OADM based on fiber Bragg grating(FBG),The main works and innovations are as follows:(1)Firstly,the research background of this paper and some typical structures of OADM are introduced,based on the foundation theory of coupling mode theory and transfer matrix method for fiber gratings,the transmission and reflection characteristics of FBG are derived,secondly,introducing the methods of self-graved Bragg grating in the experiment,and then analyzing on the stress and temperature tuning principle of fiber grating.(2)Simulation and experiments are carried out to examine the performance of OADM based on FBG and circulator,analyzing the similarities and differences between the experimental and simulation results,optimization experiments to study the structural parameters of OADM.And then the principle of spectral output characteristics of the Mach-Zehnder Interferometer are analyzed,studying on the two key factors that affect the performance of OADM based on FBG and Mach-Zehnder Interferometer,which are efficiency of beam splitting and isolation.Finally the structure characteristic of this type of OADM has carried on the experiment study.(3)A novel structure of OADM based on the Mach-Zehnder interferometer,tunable FBG and circulator is proposed,and analyzing its channel wavelength of upper and lower carrier,direct connection function and download channel wavelength of tunability by simulation.Experimental tests two important parameters of the novel OADM that characterize its performance,which are channel isolation and homodyne crosstalk.the basic function of the device and the various insertion loss,the OADM realized the single or multiple wavelength of upper and lower carrier.(4)A novel pure bending beam with linear tuning symmetric structure is designed,Theoretical analysis the tuning characteristics of beam for FBG,secondly,experiment respectively studied on the tuning characteristics of beam of single or double ended on FBG.The experiment measured the tuning range,tuning sensitivity,linearity and the relationship between the beam of single or double ended tuning.Compared the similarities and differences between the structure and piezoelectric ceramic tuning.