A Study On OFDM-Based WDM-PON System

PON technology is an important realization of FTTx technologies. So far, two kinds of using time-division multiplexing PON technology EPON and GPON are large-scale application.The majority view that the overall wire-speed TDMA PON and power budget can not meet the needs of the future network development. PON power budget is not only limited the splitter ratio,but also limits the distance from the OLT to the ONU. These issues will be with the wavelength division multiplexing passive optical networks (WDM-PON) the introduction of ease. In the WDM-PON, each ONU is assigned a single wavelength, which will provide greater bandwidth for each ONU.And each ONU can operate at its own rate rather than the overall(WDM) rate.Since each ONU through the physical wavelengths are separated, so network security and network convergence problem can be fundamentally solved.The high-speed access realization of WDN-PON system has always been the interest of domestic and foreign studies.Recently the main ONU access rate is over 1Gbit/s.Due to the cost concern, the study on WDM-PON system which access rate exceeds 2.5Gbit/s or even 10Gbit/s is comparatively less focused.This issue proposed a tunable-laser based WDM-PON system with ONU access rate of lOGbit/s. Take the advantage of OFDM technology to compress spectrum, and reduce the device requirements.Through the combined solution of simulation experiment and theoretical analysis,system performance is analyzed and its viability is verified.This article is the author's theory during the post-graduate study and a summary of the actual research and development,divided into the following five chapters:Chapter I deal with some background knowledge of the research, and the author of some of the work during graduate the content and outcomes;ChapterⅡintroduces the principles of WDM-PON system, network programs and key equipments.By analyzing WDM-PON technology advantages and present business situation,it indicates the hotspots and shortfalls of this research,while also providing the study focus of this issue and WDM-PON future development tendency.Chapter III study of the OFDM WDM-PON system, crosstalk characteristics of the theoretical models,experimental measurement and spectrum analysis of the impact of crosstalk.Chapter IV, as the result of the simulation experiment, the sensitivity, chromatic dispersion, light power, transmission distances,and system cost are theoretical analyzed, which consequently verifies the system viability.Finally, the author pointed out that the lack of existing work on the next stage of work is prospected.