A new algorithm based on a transfer matrix method is given to analyze a new distributed feedback(DFB)structure-distributed phase shift in DFB laser.In the small signal analysis,a new model is presented with this algor...A new algorithm based on a transfer matrix method is given to analyze a new distributed feedback(DFB)structure-distributed phase shift in DFB laser.In the small signal analysis,a new model is presented with this algorithm.Compared withλ/4 phase-shifted DFB and three phase shifted DFB lasers,this structure shows superior characteristics in both static and dynamic behavior.展开更多
Orthogonal frequency division multiplexing （OFDM） is attracting more attention for its capability of high speed transmission. However, the OFDM possesses an obvious shortage in its high ratio of the peak power to th...Orthogonal frequency division multiplexing （OFDM） is attracting more attention for its capability of high speed transmission. However, the OFDM possesses an obvious shortage in its high ratio of the peak power to the average power （PAPR）, which has become the main issue holding it back to be applied to the broadband satellite communication system. OFDM combined with time division multiplexing （TDM）, dividing the subcarriers of OFDM into some blocks in time tune, can decrease the high PAPR of OFDM. Meanwhile, the advantages of OFDM can be preserved. In this paper, OFDM/TDM is applied to the broadband satellite communication system. This paper theoretically analyses OFDM/TDM system model as well as its restraining effect on PAPR, and proposes frequency domain multiplexing-pilot （FDM-Pilot） channel estimation algorithm. Simulation results show OFDM/TDM in broadband satellite communication system has approving performance and decreased the PAPR.展开更多
Dense wavelength division multiplexing(DWDM)system is the ultimate selection as an optical communica-tion system because of its high speeds and capacities.However,the fiber nonlinear effects and polarization mode disp...Dense wavelength division multiplexing(DWDM)system is the ultimate selection as an optical communica-tion system because of its high speeds and capacities.However,the fiber nonlinear effects and polarization mode dispersion severely limit the performance of the system when signal propagates at 40 Gbit/s in a single channel.The coupled nonlinear Schrödinger equations of a single channel in DWDM,which are all considered factors of group veloc-ity dispersion(GVD),self phase modulation(SPM),cross phase modulation(XPM),four wave mixing(FWM)and polarization mode dispersion(PMD),are derived,while their number results are obtained with extended split-step Fourier method.Finally,to analyze the impacts of the fiber nonlinear effects and PMD on the optical communication system,the simulated results of an 8×40 Gbit/s DWDM system are discussed under different conditions respec-tively.展开更多
文摘A new algorithm based on a transfer matrix method is given to analyze a new distributed feedback(DFB)structure-distributed phase shift in DFB laser.In the small signal analysis,a new model is presented with this algorithm.Compared withλ/4 phase-shifted DFB and three phase shifted DFB lasers,this structure shows superior characteristics in both static and dynamic behavior.
基金supported by the National Natural Science Foundation of China (61271281)the National Hi-Tech Research and Development Program of China (2013AA013301, 2013AA013303, 2012AA01A504)+1 种基金the Fundamental Research Funds for the Central Universities (24820122012PTB0004, 24820132013RC0201)the International Science & Technology Cooperation Program of China (2012DFA11410)
文摘Orthogonal frequency division multiplexing （OFDM） is attracting more attention for its capability of high speed transmission. However, the OFDM possesses an obvious shortage in its high ratio of the peak power to the average power （PAPR）, which has become the main issue holding it back to be applied to the broadband satellite communication system. OFDM combined with time division multiplexing （TDM）, dividing the subcarriers of OFDM into some blocks in time tune, can decrease the high PAPR of OFDM. Meanwhile, the advantages of OFDM can be preserved. In this paper, OFDM/TDM is applied to the broadband satellite communication system. This paper theoretically analyses OFDM/TDM system model as well as its restraining effect on PAPR, and proposes frequency domain multiplexing-pilot （FDM-Pilot） channel estimation algorithm. Simulation results show OFDM/TDM in broadband satellite communication system has approving performance and decreased the PAPR.
基金supported by the National Natural Science Foundation of China(No.60132020)the Hi-Tech Research and Development Program of China.
文摘Dense wavelength division multiplexing(DWDM)system is the ultimate selection as an optical communica-tion system because of its high speeds and capacities.However,the fiber nonlinear effects and polarization mode dispersion severely limit the performance of the system when signal propagates at 40 Gbit/s in a single channel.The coupled nonlinear Schrödinger equations of a single channel in DWDM,which are all considered factors of group veloc-ity dispersion(GVD),self phase modulation(SPM),cross phase modulation(XPM),four wave mixing(FWM)and polarization mode dispersion(PMD),are derived,while their number results are obtained with extended split-step Fourier method.Finally,to analyze the impacts of the fiber nonlinear effects and PMD on the optical communication system,the simulated results of an 8×40 Gbit/s DWDM system are discussed under different conditions respec-tively.
