Studies On Transmission Convergence Framing Sublayer In ONU Of GPON

The IT technology initiated various applications of network current play an important role both in the industrial and human's daily life. Thus, it strongly needs the bandwith support in the present, as well as the future, and which are able to address the key issue for overcoming the last step of the bottleneck of broad bandwith access network. PON technique has been developed for nearly 20 years, however, the latest effort com-out a new solution has emerged into the optical access market place---- GPON, offering unprecedented high bit-rate support while enabling transport of multiple services.Based on the development history of PON, this paper analyses and compares the advantage and disadvantage of three mainstream techniques of PON– APON, EPON and GPON. Meanwhile, further, we explains the key technique of GPON --- the GEM sealing. After demonstrating the analysis of the main available three structures of GPON inter-net structure, the paper picks up one of those as a solution.This paper proposed a design ONU port system architrave of GPON, choose the chips according to the design, the related circuit are also presented.The main purpose is to investigate the design of the TC frame for the ONU-port; the concept from top to bottom is employed, and then divided the TC frame as several basic sub-unit. Then the essential principle and algorithm was discussed. The detail function for each sub-unit, and their connection, as well as the all the system works time-order, simulation also demonstrated. It could operate the exactly logic function for TC framing sublayer.The further work need to carry out in the next step is also pointed out in the final。...