Study On Re-Modulation WDM-PON System Based On RSOA

At present, Most countries have used fiber communication in long haul backbone networks. Backbone networks always using WDM (Wavelength Division Multiplexing) technology. WDM technology through multiple wavelength set to a single optical fiber for transmission, realize the large capacity transmission. Judging from the current results, With the wide use of DWDM technology in long haul backbone network, the main problem of network transmission capacity has been resolved.WDM technology will be applied to the access network, combining with Passive Optical Network (PON) to achieve high-speed and large-capacity transmission, is a research hotspot in recent years.The key problem of WDM-PON technology is using cheap, colorless ONU to avoid the increase cost in installation, operation and maintenance. So far, there are three ways to realize colorless ONU: Optical carrier source method, Optical spectrum intersected, re-modulation technology, among them, the re-modulation is a better way to realizing colorless ONU. Therefore, this article discussed the large capacity PON system technology, comprehensively study re-modulation WDM-PON system which based on RSOA; and analyses the system performance of Manchester coding RSOA-WDM-PON; Put forward to realize high speed re-modulation WDM-PON of OFDM transmission mode, We wish it should be importance to the development and research on WDM-PON technology. the writer has done the following work:1. Studied the internal and abroad development instances of optical access network. Describe the international developments, structures and characteristics of WDM-PON. Analyses its advantages compared to traditional and existing Describes WDM-PON international developments, structure and characteristics. Compare with traditional and existing PON, Analyses its advantages and problem.2. Describe the ways to realize colorless ONU, emphatically analyses based on reflection semiconductor optical amplifiers (RSOA) re-modulation WDM-PON system, and analyses RSOA working principle and characteristics theoretically.3. Study on using Manchester coding based on RSOA re-modulation WDM-PON system performance. Via simulation, gives constructing Manchester coding method, Analysis dispersion effect the performance of the system; Analysis when the power input RSOA are different, the performance of the uplink transmission, when the input power is large enough, RSOA can reach the deep saturation, effectively erasing the downlink signal and Inhibition reflection noise, to improve the performance of uplink transmission comparative analysis downlink use NRZ and Manchester coding, respectively, the uplink transmission performance, Through analysis, the Manchester coding can effectively improve the system received power, realize high-speed and reliable transmission, the downlink signal using Manchester coding system has better performance than NRZ coding system performance.4. Exploratory proposed a OFDM/OOK transmission mode for the re-modulated WDM-PON system, using OFDM signal has a high dispersion tolerance and efficient frequency spectrum utilization, realize high speed downlink transmission, analyzing system downlink transmission performance and analyses uplink transmission performance; using OFDM modulation can achieve 10Gb/s downlink transmission, Equalization technology realize dispersion compensation and improve the system BER performance.