Design Of Full-bandwidth ROADM And Its Application In Optical Fiber And Wireless Convergence Network

With the arrival of the big data age,the Internet scale expands rapidly and the new services and the quantity of information interaction grow rapidly.Future optical networks need to meet more requirements because of the booming Internet.In the new Internet era,large capacity,ultra-high speed,long distance,and dynamic resources allocation become the core requirements in optical networks.To comply with the future optical network development trend and improve the flexibility of network,the network node devices need to be able to add,drop and route various services,and dynamically allocate bandwidth resources.In mobile communications,the development of emerging services leads to a shortage of spectrum resources.Fully digging the millimeter-wave bands for communications becomes the new requirement in the 5G era.In order to make full use of the millimeter-wave bands and improve the utilization of spectrum,the radio over fiber(RoF)technology is an effective solution.The RoF system,combining the advantages of the optical fiber and wireless,is of great significance in reducing transmission link loss,improving system transmission quality and enabling flexible access.In the context of the big data and 5G,this thesis provides a scheme of the flexible controllable reconfigurable optical add-drop multiplexer(ROADM)in response to the requirements of devices in next-generation optical networks.Meanwhile,the novel RoF system based on the single-sideband modulation is proposed to improve the utilization of millimeter-wave spectrum.Based on the flexible and dynamic wavelength allocation of ROADM,the thesis realizes the application of ROADM in optical fiber and wireless convergence network.Firstly,the future networks develop toward dynamic,flexible and reconfigurable direction.This thesis provides a scheme of the full-bandwidth ROADM,which is conducive to the control and distribution of network resources.The system model is designed and builded in simulation environments,and the system parameters are optimized based on this model.The simulation results confirm that the system meets the development requirements of future optical networks and provides an effective solution for core device design in next-generation network architecture.And then in the thesis,the bidirectional RoF system is designed to realize the transmission of millimeter over optical fiber.The author design two RoF systems based on the optical coupling single-sideband modulation(O-SSB)and electrical coupling single-sideband modulation(E-SSB).respectively.The system performance is analyzed and compared,the results shows that the O-SSB format can reduce nonlinear distortion.In addition,the system implements full-duplex communication using center-carrier reuse technology,which makes the base unit colorless,reduces system cost,and provides theoretical support for millimeter-wave access.Finally,according to the advantages of ROADM,such as full-bandwidth,dynamic,and wide tuning range,the RoF systems are optimized and designed.Combined with the function of ROADM dynamically allocating wavelength resources,the author simulates the application of ROADM in optical fiber and wireless convergence access network.The thesis presents a multi-service convergence access optical fiber and wireless communication system,which realizes the application in many scenarios.