Research On Compensation Of Laser Phase Noise For Optical Coherent OFDM Systems

The advent of the Internet fundamentally changed the underlying information com-munication infrastructure.The phenomenal bandwidth growth led to worldwide telecom build out.It does not appear that the growth of Internet will slow in the foreseeable future.New emerging applications,such as VR and AR,will futher triple the bandwidth demand by 2011,requiring IP link capacity scalable to 1 Tb/s.Optical coherent OFDM structure is well known for its flexibility to system update which reduce the cost and investment.However,CO-OFDM system is prone to lase phase noise,which induces common phase error and intercarrier interference.This thesis is work on solution to mitigate and remove the effect of laser phase noise.A novel low-complexity phase noise(PN)compensation approach is pro-posed.By employing Radio Frequency pilot(RFP),the PN is estimated and compensated in the frequency domain(FD),which is free of the penalty induced by nonideal low-pass filters in the conventional RP-pilot method.In addition,the computational complexity is greatly reduced due to the elimination of the narrow-band filter and the simplification of PN compensation in the frequency domain.The numerical simulation exhibits the superiority of the proposed FD-RFP in terms of performance and computational complexity.