Optimization Of Device Characteristics Based On RSOA And Transmission Characteristics Of ONU In WDM-PON

With the development of the fifth generation of mobile communication technology,Blue-ray video broadcast,high-definition mobile video calls,ultra-clear interactive network television and other related communication services have been constantly updated and widely applied in the daily life of modern society.At the same time,the demand for bandwidth required by new technologies for mobile networks is also urgent,which challenges the speed and capacity of data transmission in optical communication technology.Correspondingly,researchers in related industries are also constantly innovating and applying new key application technologies such as peripheral facilities and architectures.Among them,widening the capacity of optical network transmission system and improving the utilization rate of bandwidth are the most important problems that need to be broken through.Based on the optical fiber transmission system,the reflective optical semiconductor amplifier,as a small-size,low-cost,easily integrated and low power consumed modulator,with the function of modulation and amplification,perfectly meets the requirements of the modulator in the current optical network unit.In addition,the reasonable use of chirp effect can achieve the function of extending transmission distance and making up for loss in transmission,which can also give useful and guiding advices for the design and production of modulator.Based on the existing SOA broadband steady-state model and the efficient steady-state model,the structure of the active zone in RSOA is modified,and the parameters are modified in the modeling to make the model more in line with how RSOA works.The multi-order iterative algorithm is used in the simulation to much accurately calculate the concentration of carriers in active zone when RSOA is working,which makes the results of simulation and data more accurate.Finally,the effect of bias current and input optical power on RSOA gain and noise index is studied and analized.A multi-ONU network transmission system based on SOA direct-modulation is designed,which uses the no-return-zero as the formation of the up-stream and down-stream signal transmission.And the dual-directional transmission system of single ONU and multi-ONU at different transmission rates is simulated and compared.The results of simulation show that the received sensitivity of down-stream and up-stream can reach-32.5d Bm and-27.6d Bm respectively under the condition of direct detection,and can be widely used in the low-cost DWDM-PON field.The principle of chirp effect and the effect of chirp on optical signal are introduced,the principle of common modulation techniques is studied and discussed.Besides,the principles as well as advantages and disadvantages of three common modulation devices are discussed.By setting up the simulation link,the observation of chirp effect in the four modulators in modulation is realized,and the advantages and disadvantages of these modulators in the chirp effect are analyzed and compared.Besides,the EAM is simulated for long-distance transmission performance at 10Gb/s signal rate on the basis of previous work.