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A research on the architectures of large capacity optical access networks

With the continuous emergence of various new services, users have put forward higher and higher demands for the bandwidth of the optical access network. The next-generation passive optical network (NG-PON) can break the bandwidth bottleneck of the access network and has become one of the important research topics in the field of the optical access network. In this paper, the architectures of NG-PON are investigated. Four kinds of one-dimensional PON architectures (TDM-PON, WDM-PON, OFDM-PON, and SDM-PON) and three multiple-dimensional PON architectures (WDM-TDM PON, MDM-TDM PON, SDM-MDM PON) are introduced. The key technologies and problems of these architectures are discussed in detail.