Research And Implement Of GPON System ONU MAC Layer's Uplink

In recent years, the technology of access network develops incessantly. At present, access network mostly include xDSL, hybrid access technology, fiber access technology and wireless access technology. In the field of wired solutions, fiber access technology becomes the mainstream technology of access network step by step due to their bandwidth capacity and litter attenuation. Passive optical network (PON) is the fiber access technology that attracts the most attention. PON has experienced three modes, namely APON, EPON and GPON. GPON holds the strongpoints which contain high efficiency, high speed, high bandwidth utilizing rate and support of whole service, therefore GPON is considered as the most advanced technology of PON.The technology character of GPON mainly shows on medium access control (MAC) layer. Many key technologies are achieved on MAC layer such as dynamic bandwidth assignment, coding and ranging. This dissertation focuses on the research and implement of GPON system ONU MAC layer's upstream link, we simulate and implement every module of upstream link using Verilog HDL language, and study the dynamic bandwidth assignment algorithm. The main work and progeny of dissertation is as follow.1. The dissertation introduces the actuality and development of access network, three main kinds of passive optical networks such as APON, EPON and GPON;2. From the definitions of GPON, we illuminate GPON's standards, system configuration, recommendation model, transmission multiplexing mode and frame format;3. We design the whole structural drawing of ONU medium access control layer, introduce the function of every module, and put forward the solution of upstream access;4. Analyzing in detail every module of upstream link, we simulate and implement the modules using Verilog HDL language on the development environment of Quartus II;5. We introduce the key technology of MAC layer: dynamic bandwidth assignment, and put forward a dynamic bandwidth assignment algorithm based on bandwidth requirement, it can improve bandwidth utilizing rate.6. At last, we summary the dissertation, and put forward the expectation for the next research.