Research On The OUN MAC Layer Of GPON System And Design In FPGA

Access network provides a bridge for users to access metropolitan area network andbackbone network, and is the "last mile"of the information transmission channel. In recent years,with the rapid emergence of new service requirements, access network technology began toreceive extensive attention. In the field of wireline access technologies, GPON uses GenericFraming Protocol to package and map Ethernet, TDM, ATM and other businesses and it hasmany features like high-bandwidth, high-speed, efficient transmission and flexible accessing. SoGPON is considered as an ideal technology for broadband access network business andintegrative reconstruction by most telecommunication operators.First, this paper introduces the development of PON and compares three currently popularPON technologies, then points out the advantages and prospects of GPON.Second, it introduces some related protocols in GPON ruled by ITU-T G.984 and analyzesthe composition, protocol hierarchy, frame structure, work principle and key technologies ofGPON system. Then it discusses the businesses based on GPON.This paper mainly designs GPON user terminals. Based on the analysis of user terminalmodel, it adopts the idea of hierarchical design, takes FPGA as the processing core of layerMAC and designs the schematic diagrams of each functional module. Finally it gives thecomplete plan of this design.MAC is the core layer of GPON system, and layer TC which is based on generic framingprotocol can packet a variety of businesses. This paper studies the protocol and frame structureof layer TC, and puts forward a modularized proposal focused on the framing sub-layer. InQuartus II and taking Arria GX EP1AGX60DF780C6 as the target device, it realizes the overallsimulation of the framing sub-layer under FPGA by using Verilog HDL.Finally, the work of this paper is summarized.