公开(公告)号：US20240056109A1

公开(公告)日：2024-02-15

申请号：US18228825

申请日：2023-08-01

申请人： FUJITSU LIMITED

发明人： Ke ZHANG ,  Zhenning TAO

IPC分类号： H04B1/04 ,  H04B10/50

CPC分类号： H04B1/0475 ,  H04B10/50 ,  H04B2001/0408

摘要： An optical signal transmission device and method based on digital predistortion in a symbol domain is provided. The optical signal transmission device includes: a memory; and a processor coupled to the memory to control execution of a process to: perform digital predistortion processing on a symbol sequence of a signal to be transmitted to obtain a digital predistortion processed signal; perform short-pulse shaping processing on the digital predistortion processed signal to obtain a short-pulse shaping processed signal, wherein a memory length introduced by the short-pulse shaping processing is less than or equal to a memory length of the optical transmitter; and generate and transmit an optical signal based on the short-pulse shaping processed signal.

公开(公告)号：US20230082707A1

公开(公告)日：2023-03-16

申请号：US17894711

申请日：2022-08-24

申请人： FUJITSU LIMITED

发明人： Ke ZHANG ,  Zhenning TAO

IPC分类号： H04B17/345 ,  H04L1/20

摘要： The present disclosure provides a method and apparatus for generating equivalent nonlinear noise. The method includes randomly generating white noise obeying zero-mean Chi-square distribution; and filtering the input white noise by using an equivalent nonlinear noise spectrum as an equivalent nonlinear filter to obtain the equivalent nonlinear noise. According to the embodiments of the present application, equivalent nonlinear noise may be generated based on zero-mean Chi-square distribution random variables combined with equivalent nonlinear noise spectrum filtering, and more accurate equivalent nonlinear noise than the related art may be generated, thus accurately evaluating an influence of nonlinearity of devices on Bit Error Rate (BER).

公开(公告)号：US20220166520A1

公开(公告)日：2022-05-26

申请号：US17506133

申请日：2021-10-20

申请人： Fujitsu Limited

发明人： Xiaofei SU ,  Tong YE ,  Zhenning TAO ,  Chengwu YANG

IPC分类号： H04B10/58 ,  H04B10/61 ,  H04B10/294

摘要： A performance estimation apparatus and method for a nonlinear communication system and an electronic device. The nonlinear communication system is equated with by an equivalent model including an equivalent linear model and an equivalent additive noise model, and the equivalent additive noise outputted by the equivalent additive noise model is mathematically uncorrelated to the signal inputted into the equivalent model. Performances of the nonlinear communication system of different modulation formats at different baud rates may be accurately estimated.

公开(公告)号：US20210111789A1

公开(公告)日：2021-04-15

申请号：US17018180

申请日：2020-09-11

申请人： Fujitsu Limited

发明人： Jingnan LI ,  Zhenning TAO ,  Yangyang FAN

IPC分类号： H04B10/077 ,  H04B10/564 ,  H04B10/079 ,  H04B10/2537 ,  H01S3/30

摘要： Embodiments of this disclosure provide a method and apparatus for establishing a transmission impairment decomposition model for a Raman amplified system and a system. The method includes: converting a Jones vector of a test signal after passing through a Raman amplified system into a Stokes vector; calculating transmission impairments to which the test signal is subjected by using the Stokes vector according to a pre-established transmission impairment decomposition model; and substituting values of the transmission impairments into the pre-established transmission impairment decomposition model to obtain a complete transmission impairment decomposition model used for estimating transmission impairments.

公开(公告)号：US20180102841A1

公开(公告)日：2018-04-12

申请号：US15729008

申请日：2017-10-10

申请人： Fujitsu Limited

发明人： Zhenning TAO ,  Ying ZHAO

IPC分类号： H04B10/079 ,  H04B10/25

CPC分类号： H04B10/07953 ,  H04B10/073 ,  H04B10/07955 ,  H04B10/25

摘要： A system performance prediction method and apparatus where the transmission system performance prediction apparatus includes: a calculating unit configured to calculate system performance at second power according to first power of a signal and a first noise component generated by the system at the first power. With the above system performance prediction apparatus, by changing power and predicting the system performance by using noise components at different power, accuracy of the prediction of the system performance may be improved, and problems in the related art may be avoided that in predicting system performance, a large-capacity database needs to be prepared and accuracy of the prediction of the system performance is low.

公开(公告)号：US20180076888A1

公开(公告)日：2018-03-15

申请号：US15664105

申请日：2017-07-31

申请人： Fujitsu Limited

发明人： Hao CHEN ,  Zhenning TAO

IPC分类号： H04B10/079

CPC分类号： H04B10/07955 ,  H04B10/614 ,  H04B10/616

摘要： A measurement method and apparatus for residual direct-current components and a system where the measurement method includes: selecting a section of data of a first predetermined length respectively from received signals in two polarization states; performing a coordinate transform on the two selected sections of data to obtain a group of vectors of Strokes space; and determining a difference between power of the residual direct-current components according to the group of vectors of Strokes space. With the embodiments of this disclosure, residual direct-current components of an optical transmitter may be measured at a receiver end of a coherent optical communication system, thereby avoiding diagnosis errors of a communication network, and improving performance of the communication system.

公开(公告)号：US20170244641A1

公开(公告)日：2017-08-24

申请号：US15436110

申请日：2017-02-17

申请人： Fujitsu Limited

发明人： Lei LI ,  Bo LIU ,  Zhenning TAO

IPC分类号： H04L12/851 ,  H04L12/26

CPC分类号： H04L47/24 ,  H04L43/08 ,  H04L67/141 ,  H04L69/00 ,  H04L69/40

摘要： A transmission control method and apparatus for network services and controller. The transmission control method for network services includes: negotiating, before start of the network services, operational modes supported by each of links, and detecting quality of services in the operational modes supported by each of the links; grouping all network services to be transmitted according to requirements of the network services on quality of services and the quality of services in the operational modes supported by each of the links, and allocating links and operational modes for each of the groups; and designating a link for each of the network services in the groups according to the links and operational modes allocated for each of the groups. Hence, abilities of transmission quality detection and adjustment of a multi-carrier optical communication system may be used to satisfy quality requirements of different network services.

公开(公告)号：US20170170902A1

公开(公告)日：2017-06-15

申请号：US15375714

申请日：2016-12-12

申请人： FUJITSU LIMITED

发明人： Yangyang FAN ,  Zhenning TAO ,  Liang DOU

IPC分类号： H04B10/2507 ,  H04B10/079 ,  H04B10/58

CPC分类号： H04B10/25073 ,  H04B10/0731 ,  H04B10/07955 ,  H04B10/58

摘要： A method and apparatus for measuring a filtering characteristic, pre-equalizer and communication equipment. The method includes: obtaining a receiving signal after two measurement signals of different spectral ranges pass through different filtering modules and are received at the same time at a receiving end; and determining a part of a filtering characteristic of a receiving end and a part of a joint response according to a nonoverlapped spectral part of the two signals in the spectrum of the receiving signal.

公开(公告)号：US20170104577A1

公开(公告)日：2017-04-13

申请号：US15291141

申请日：2016-10-12

申请人： FUJITSU LIMITED

发明人： Liang DOU ,  Zhenning TAO

IPC分类号： H04L7/00

摘要： An estimating apparatus for bias drift of a transmitting end modulator, a compensating apparatus, a receiver and a method are disclosed. Estimation and compensation of the bias drift are performed directly at the receiving end according to phase recovered received signals, with no need of providing an extra bias control circuit at the transmitting end. Estimating and compensating for the bias drift includes recovering received signals by removing a frequency difference and a phase difference between a transmitting end laser and a receiving end laser producing phase recovered received signals, estimating the bias drift of the transmitting end modulator according to the phase recovered received signals and compensating the bias drift of the transmitting end modulator in a receiver.

公开(公告)号：US20150117576A1

公开(公告)日：2015-04-30

申请号：US14524026

申请日：2014-10-27

申请人： FUJITSU LIMITED

发明人： Weizhen YAN ,  Lei LI ,  Zhenning TAO

IPC分类号： H04L27/26 ,  H04L25/03 ,  H04L7/00

CPC分类号： H04L27/2662 ,  H04L7/0041 ,  H04L25/03821 ,  H04L27/2665 ,  H04L27/2672 ,  H04L27/2675

摘要： Embodiments of the present invention provide a timing synchronization apparatus and method for multi-carrier modulation signals. Wherein the apparatus includes: a predicting unit configured to denoise delay of symbols received before a currently received symbol, and to predict delay of the currently received symbol or of a symbol received after the currently received symbol according to the denoised symbol delay and a sampling clock frequency offset; and a timing synchronization unit configured to perform timing synchronization according to a predicted value of the delay of the currently received symbol or of the symbol received after the currently received symbol. With the apparatus and method, a signal to noise ratio of multi-carrier modulation signals may be effectively improved, and an effect of a timing error on a communication system may be lowered, thereby improving performance of the communication system.

摘要翻译： 本发明的实施例提供了一种用于多载波调制信号的定时同步装置和方法。 其中，所述装置包括：预测单元，被配置为对当前接收到的符号之前接收到的符号进行去噪延迟，并且根据去噪符号延迟和采样时钟来预测当前接收符号或当前接收到的符号之后接收到的符号的延迟 频偏; 以及定时同步单元，被配置为根据当前接收的符号或当前接收的符号之后接收的符号的延迟的预测值来执行定时同步。 利用该装置和方法，可以有效地提高多载波调制信号的信噪比，并且可以降低定时误差对通信系统的影响，从而提高通信系统的性能。