公开(公告)号：US20140205283A1

公开(公告)日：2014-07-24

申请号：US13901766

申请日：2013-05-24

Applicant: NEC Laboratories America, Inc.

Inventor： IVAN B. DJORDJEVIC ,  Lei Xu ,  Ting Wang

IPC: H04B10/2581

CPC classification number: H04B10/2581 ,  H04B10/516 ,  H04L1/0041 ,  H04L5/0008 ,  H04L5/0023 ,  H04L27/3405 ,  H04L27/3422

Abstract: Systems and methods for data transport are provided which encode streams of data using low density parity check (LDPC) encoders and map data streams to symbols, by assigning bits of symbols to a signal constellation and associating bits with constellation points. Constellation points are generated using a D-dimensional optimum signal constellation design (OSCD) method. The OSCD determines an optimum source distribution for an optical channel, generates D-dimensional training sequences from the optimum source distribution, determines new signal constellation points as the center of mass for each D-dimensional cluster of points, and repeats these steps until convergence or until a predetermined number of iterations is reached. Coordinates obtained by the D-dimensional OSCD method are stored in a look-up-table (LUT), points are selected from the LUT using encoded data streams, coordinates are input into a D-dimensional modulator after digital-to-analog conversion (DAC), and a modulated signal is transmitted over an optical medium.

Abstract translation: 提供了用于数据传输的系统和方法，其通过使用低密度奇偶校验（LDPC）编码器将数据流编码并将数据流映射到符号，通过将符号的位分配给信号星座并将比特与星座点相关联。 使用D维最佳信号星座设计（OSCD）方法生成星座点。 OSCD确定光通道的最佳光源分布，从最佳光源分布生成D维训练序列，将新的信号星座点确定为每个D维聚类点的质心，并重复这些步骤直到收敛或 直到达到预定次数的迭代。 通过D维OSCD方法获得的坐标被存储在查找表（LUT）中，使用编码数据流从LUT中选择点，在数模转换之后将坐标输入到D维调制器（ DAC），并且调制信号通过光学介质传输。

公开(公告)号：US20140079164A1

公开(公告)日：2014-03-20

申请号：US14032449

申请日：2013-09-20

Applicant: NEC Laboratories America, Inc.

Inventor： Shaoliang Zhang ,  Ting Wang

IPC: H04L7/04

CPC classification number: H04L7/042 ,  H04L27/2601 ,  H04L27/2613 ,  H04L27/2657 ,  H04L27/2663 ,  H04L27/2671 ,  H04L27/2672 ,  H04L27/2675

Abstract: A training symbol with two identical halves as well as a pilot-tone at a center frequency is used for both timing synchronization and carrier frequency offset estimation. A timing synchronization is achieved by finding a peak of a cross-correlation function of the two halves in the first symbol. A fraction part of the frequency offset FO is then calculated from a phase difference between the two halves of the first training symbol. Then, the received signal is compensated for the fraction part of FO, and, an integer part of the FO is obtained by counting the shifted positions of the pilot-tone peak in the frequency domain.

Abstract translation: 具有两个相同的一半的训练符号以及中心频率的导频被用于定时同步和载波频率偏移估计。 通过找到第一符号中两个半部的互相关函数的峰值来实现定时同步。 然后根据第一训练符号的两半之间的相位差来计算频率偏移FO的分数部分。 然后，对FO的分数部分补偿接收到的信号，并且通过对频域中的导频音峰的偏移位置进行计数来获得FO的整数部分。

公开(公告)号：US20130272711A1

公开(公告)日：2013-10-17

申请号：US13862407

申请日：2013-04-13

Applicant: NEC LABORATORIES AMERICA, INC.

Inventor： Ankitkumar Patel ,  Philip Nan Ji ,  Ting Wang

IPC: H04J14/02

CPC classification number: H04J14/0227 ,  H04J14/0238 ,  H04J14/0257 ,  H04J14/026 ,  H04J14/0267

Abstract: Hybrid application of the generic evolution and simulated annealing methods are used to solve routing, wavelength assignment, and spectrum allocation sub-problems of a light-tree establishment problem in a flexible wavelength division multiplexing FWDM optical network.

Abstract translation: 通用演化和模拟退火方法的混合应用用于解决灵活波分复用FWDM光网络中光树建立问题的路由，波长分配和频谱分配子问题。

公开(公告)号：US20130259475A1

公开(公告)日：2013-10-03

申请号：US13855384

申请日：2013-04-02

Applicant: NEC LABORATORIES AMERICA, INC. ,  NEC CORPORATION

Inventor： Philip N. Ji ,  Ryuji Aida ,  Ting Wang

IPC: H04Q11/00

CPC classification number: H04Q11/0005 ,  H04L12/28 ,  H04Q11/00 ,  H04Q2011/0016

Abstract: Methods and systems for optical communication in a submarine network are provided. An input signal is received from a terminal at a reconfigurable branching unit (BU), and the input signal is split into at least two parts, with one part being associated with one or more trunk terminals and another part being associated with one or more branch terminals. Each of one or more spectrum channels are selected and individually switched to one of a plurality of paths using at least one wavelength selective switch (WSS), with the at least one WSS being configured to transmit the one or more spectrum channels to their respective target output port and to combine signals switched to a specific port into a wavelength division multiplexing (WDM) signal. Individual spectrum channels are filtered out using at least one wavelength blocker (WB).

Abstract translation: 提供了海底网络光通信的方法和系统。 在可重构分支单元（BU）处从终端接收输入信号，并且将输入信号分成至少两部分，其中一部分与一个或多个中继终端相关联，另一部分与一个或多个分支 终端。 使用至少一个波长选择开关（WSS）来选择一个或多个频谱信道中的每一个并且单独地切换到多个路径中的一个，其中所述至少一个WSS被配置为将一个或多个频谱信道发送到它们各自的目标 输出端口并将切换到特定端口的信号组合成波分复用（WDM）信号。 使用至少一个波长阻挡器（WB）滤除各个频谱通道。