Design Of Optical OFDM Transmission Based On 10Gbit/s-class Devices

OFDM(Orthogonal Frequency Division Multiplexing,OFDM)technology with its high spectrum efficiency,simple system structure,excellent resistance to fading,interference ability and other characteristics,has become one of the important areas of current broadband wireless communications technology.However,until 2001,researchers noticed the OFDM technology can effectively time multimode optical fiber mode dispersion suppression,people began to research and develop OFDM technology in the optical transmission system.Since the optical OFDM technology uses advanced digital signal processing technology,it can effectively reduce system costs,thereby providing cost-efficient solutions.Also OFDM technology can resist dispersion in fiber channel effectively and has efficient spectrum utilization,it is possible to significantly reduce the complexity of the optical networks system.In the future,a variety of new network applications and services will continue to emerge,and optical OFDM technology can take full advantage of the system time-domain resources and the frequency-domain resources for the business needs of different users for flexible allocation,improving the utilization of the network greatly.In this paper,we study the optical OFDM technology and propose a solution of OFDM technology based on 10Gbit/s level devices,through its basic principles,techniques and related algorithms to achieve in-depth analysis and discussion,Firstly the paper introduces the basic theory of OFDM and key technologies to achieve OFDM,including the discrete Fourier transform and cyclic prefix,then we summarize the optical communications infrastructure briefly,analyze the optical transmitters,receivers,fiber and a variety of channel loss in optical fiber communication system.The system platform is composed by MATLAB software and VPI simulation,the 40Gbit/s transmission is realized by the use of IM/DD modulation and the pre-emphasis technology on the commercial 10Gbit/s optical transmission devices.It is proved that the OFDM technology is feasible and practical in a low cost,high bandwidth for optical communication system in the future.Finally,the paper makes a summary and describes recent progress in the direct detection optical OFDM transmission systems,coherent detection optical OFDM transmission system and the future directions of optical OFDM.