Design And Implement Of Modular OADM In WDM Optical Network

OADM(Optical Add/Drop Multiplexer)is one of the key components for all-optic network.Many types of OADM devices have been demonstrated in recent years,but most available OADMs are inflexible,with the adding/dropping of specific wavelengths affected under preplanned or manual control.Thus their applications are largely restricted.Developing reconfigurable OADMs with excellent performances is a trend in optical communication field.In this thesis,OADM node based on AOTF(Acousto-Optic Tunable Filter) for the Metropolitan Area Network(MAN)has been researched theoretically and experimentally.Firstly,we analyze the network environment of OADM,obtaining the BLSR/2(2-fiber bidirectional line switched ring),BLSR/4 and single-fiber bidirectional line switched ring and design the corresponding structure.Secondly,a new systemic architecture of OADM based on AOTF is presented after reviewing recent progress for OADM.New designs of add/drop units of OADM are also presented.The correlative key techniques are also studied.The OADM has many excellent characteristics,such as optional wavelength,short response time and wide tunable range because the add/drop wavelength can be selected randomly by changing the frequency of RF in AOTF.Finally,we implement a 4-wavelength adding unit of OADM based on AOTF theoretically,but of some reasons,an actual AOTF is not available by now.To test and verify the feasibility of the design,a 4-wavelength OADM based on Circulator & FBG designed by the simulation software PTDS(Photonic Transmission Design Suite)is implemented.We also analyze the input signals,output signals,add signal, and the output signals of particular optical devices using the spectrum analyzer through experiments of a 2-wavelength adding unit of OADM based on Circulator & FBG.and compare it with the OADM based on AOTF.