| With the rapid increase in optical fiber communication system transmission rate,polarization mode dispersion and nonlinear effects attendant problems become more serious.Conventional NRZ modulation format(NRZ)and NRZ(RZ)on transmission performance gradually stretched,looking for a new modulation format imminent.Currently,there are a lot of literature in doing exploratory research of new patterns,trying to improve the transmission efficiency of the signal and reduce the error rate and improve spectral efficiency of the signal,especially in the binary phase shift keying signal(BPSK)and binary polarization keying signal(Polsk)are the most widely studied.On the one hand is Polsk signal good power balance,good polarization characteristics,suitable for ultra high-speed network communications,but high-speed polarization control technology is very complex and costly large;on the other hand is the distribution of digital information BPSK signal in phase,the power balance,phase OOK signal than to have good anti-dispersion properties and nonlinear effects,suitable for transmitting high-speed signals.Because of different modulation formats have different anti-PMD and nonlinear properties,then between different modulation formats different networks need to do format conversion between patterns.Currently,the research of format conversion technology focused on the highly nonlinear fiber(HNLF)and a semiconductor optical amplifier(SOA)on.Compared to the highly nonlinear optical fiber,the semiconductor optical amplifier with a small,easy to integrate,enrich nonlinear effects and other features,is very suitable for applications of all-optical signal processing,and therefore all-optical format conversion SOA-based research has become Fiber an important branch of the conmmunication system.The main research work of this paper is the use of non-linear effect of SOA technology research Polsk to BPSK pattern conversion,as follows:1.In a large number of documents on the basis of research on all-optical fonnat conversion technologies are described in detail,some commmon patterns and convert common classification were analyzed,and points out the research Polsk signal to the BPSK signal pattern conversion Necessity.2.Introduction of the transmission model of SOA.In considering polarization sensitive,spectrum hole burning,the carrier is heated on the basis of ASE noise is introduced comprising polarization rotation(NRP),cross-phase modulation(XPM),cross-gain modulation(XGM)and other nonlinear effects,including SOA theoretical model,this model gives a value of SOA-based segmentation solution process.Detailed analysis of the TE and TM mode gain characteristics on;cross-phase modulation characteristics of TE and TM modes on;birefringence effect due to the phase group delay caused by injection with pump power and changes in current relations;the degree of polarization with the pump power changes in relationships.3.Presentation of the principle Polsk signal modulation and demodulation.In the survey,based on a large number of documents detailing the basis of theoretical models and simulation speed polarization encoding.It introduces several common coding scheme focuses on the high-speed polarization coding by Cross Polarization Modulation SOA technical solutions,and the use of simulation software coding polarization key signal.4.Propose a SOA-based cross-phase modulation BPSK technical solutions to achieve Polsk pattern conversion.And 40Gbit/s modulation format conversion pattern research and numerical simulation analysis.Simulation successfully achieved Polsk to BPSK code converter,to verify the feasibility of the proposed scheme.And a detailed analysis of the wavelength spacing,affect the polarization walk-off effect,the probe light power and Polsk signal simulation performance... |
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