Research On Upgrade Of Passive Optical Network Based On OFDM And Chromatic Dispersion Compensation

With the rapid development of mobile Internet, and the advent of the big data era, the bandwidth demand from users has been increasing explosively. As the "last mile" of information superhighway, access network technology has become the focus of people’s concern in recent years.Among all the available scheme, passive optical network (PON) is the most attractive. Optical orthogonal frequency division multiplexing system has the advantages of high speed, high spectrum efficiency, strong dispersion robustness, etc. Therefore, OFDM is chosen as key technology for4G mobile communication systems.In this paper, our research are conducted based on upgrade scheme of PON as well as optical dispersion compensation method in optical communication. Meanwhile, we give a brief introduction to the basics of passive optical networks, and outline the evolution and key technologies in O-OFDM systems. The main innovation of the article can be divided into two aspects. Firstly, we propose a time-division multiplexing passive optical network upgrade program based on OFDM technology, and verify its feasibility by theoretical analysis and simulation, without changing the system structure. Our scheme uses baseband and carrier signal transmission, realizing an increase of system capacity.Secondly, with regard to dispersion in optical communications, dispersion pre-compensation scheme is proposed based on optical double sideband modulation. We apply this method in the TDM-PON and DDO-OFDM-PON system. Theoretical analysis and system simulation are conducted. We test system detected signals BER curves and constellation diagram, which shows that the compensation effect is obvious and has good performance.