Research On Generation And Equalization Of Intensive Multi-carrier In High-speed And Large-capacity System

With the continuous growth of the demand for communication services,people are increasingly demanding in terms of communication capacity,transmission rate and transmission distance.Optical communication system from the original single-wavelength channel 40Gb/s,and then developed to 100Gb/s later,the laboratory has achieved Tb/s optical transmission system.For the development of high-rate transmission systems,researchers have proposed a variety of high-order complex co-modulation techniques in the field and a variety of multiplexing systems based on different dimensions,including time division multiplexing,polarization multiplexing,wavelength division/dense WDM,high-end complex format modulation,space division multiplexing.How to make the system have high transmission efficiency under high-speed and long-distance transmission conditions,large capacity and low bit error rate play an important role in the future development of optical fiber communication technology.Based on the research of dense multi-carrier generation and dense sub-carrier packet transmission and equalization in high-speed and large-capacity system,a scheme of generating single-sideband multi-carrier light source based on cascaded staggered cyclic frequency shift is designed.Transmission scheme and multi-channel receiving combined MMA equalization scheme to simulate a high rate and high-capacity optical fiber transmission system.The main research work is as follows:1)This paper presents a scheme based on cascaded staggered cyclic shift multi-carrier light source.The structure model of multi-carrier generation is designed and the main parameters such as the fr-equency shift interval of multi-carrier light source are optimized.The simulation results show that the proposed multi-carrier light source with cascade interleaving and cyclic filtering can generate frequency shift interval for the original 1/N,high-quality multi-carrier,suitable for high-speed high-capacity transmission system.2)Based on the idea of packet transmission,this paper proposes an optical transmission scheme based on uniform packet marking of dense subcarriers.The simulation results show that the proposed adaptive packet allocation scheme can greatly reduce the mutual interference between subcarriers.High-speed and high-capacity transmission system,the overall performance of the system can be improved about 3dB,better than the fixed sub-carrier packet algorithm and non-adaptive modulation algorithm.3)Based on the study of different equalization methods,this paper presents a method based on packet reception combined with MMA equalization.This method divides the received OFDM packet signal into multiple equalization channels to achieve a large amount of data distribution to each single channel among them,to solve the system due to a one-time balance brought massive data congestion and loss of information.The simulation results show that the proposed algorithm can reduce the overall bit error rate by about 3 dB compared with the traditional one-time equalization.