公开(公告)号：US11619523B2

公开(公告)日：2023-04-04

申请号：US17118529

申请日：2020-12-10

Applicant: NEC Laboratories America, Inc.

Inventor： Ming-Fang Huang ,  Hansi Liu ,  Ting Wang

IPC: G01H9/00 ,  G01D5/353

Abstract: A method for the non-destructive localization of underground optical fiber cables that utilizes distributed fiber optic sensing (DFOS) and time difference of arrival (TDOA) data associated with received signals of impulsive surface vibrations to localize the underground optical fiber cable by solving non-linear least square optimization problem(s). The method utilizes only TDOA information of received signals of impulsive surface vibrations to determine such localizations and does not require synchronization between a vibration source and DFOS receiver. The method may employ man-made impulsive vibrations to determine the localization. In operation the method involves 1) impulse-like vibration excitation and signal collection; 2) TDOA estimation of the received signals from DFOS; and 3) non-linear least square optimization applied to the TDOA information for underground optical fiber localization.

公开(公告)号：US11470117B2

公开(公告)日：2022-10-11

申请号：US17320187

申请日：2021-05-13

Applicant: NEC Laboratories America, Inc.

Inventor： Ming-Fang Huang ,  Ting Wang

IPC: H04L9/40 ,  H04B10/50 ,  H04B10/077

Abstract: Aspects of the present disclosure describe physical layer security in optical telecommunications networks wherein a filtering-based physical security is provided by a wavelength tunable distributed fiber optical sensing (DFOS) system operating simultaneously on the telecommunications network.

公开(公告)号：US11270200B2

公开(公告)日：2022-03-08

申请号：US16285870

申请日：2019-02-26

Applicant: NEC Laboratories America, Inc.

Inventor： Shaoliang Zhang ,  Fatih Yaman ,  Ting Wang ,  Eduardo Rodriguez ,  Yoshihisa Inada ,  Kohei Nakamura ,  Takanori Inoue

IPC: H04B10/61 ,  G06N3/063 ,  G06N3/067 ,  H04B10/27 ,  G06N3/08 ,  H04B10/071 ,  G06N3/04

Abstract: Aspects of the present disclosure describe a method for digital coherent transmission systems that advantageously provides low-complexity, single-step nonlinearity compensation based on artificial intelligence (AI) implemented in a deep neuron network (DNN).

公开(公告)号：US11054303B2

公开(公告)日：2021-07-06

申请号：US16783108

申请日：2020-02-05

Applicant: NEC Laboratories America, Inc.

Inventor： Junqiang Hu ,  Ting Wang

IPC: G01N21/00 ,  G01H9/00 ,  G01D5/353

Abstract: Disclosed are improved distributed optical fiber sensing systems, methods, and structures employing disparate point sensors that utilize uni-directional signal transmission via the distributed optical fiber such that a separate communications network for the disparate point sensors is not required.

公开(公告)号：US10917168B2

公开(公告)日：2021-02-09

申请号：US16719963

申请日：2019-12-18

Applicant: NEC Laboratories America, Inc.

Inventor： Ming-Fang Huang ,  Yue-Kai Huang ,  Ezra Ip ,  Ting Wang

IPC: H04B10/071 ,  H04B10/077 ,  G01H9/00 ,  G01M11/00

Abstract: Aspects of the present disclosure describe systems, methods and structures and applications of optical fiber sensing. Of significance, systems, methods, and structures according to aspects of the present disclosure may reuse and/or retrofit/upgrade existing optical fiber cables as part of optical fiber sensing that may find important societal application including intrusion detection, road traffic monitoring and infrastructure health monitoring. Combining such optical fiber sensing with artificial intelligence (AI) further enables powerful applications at low(er) cost.

公开(公告)号：US10739228B2

公开(公告)日：2020-08-11

申请号：US16258588

申请日：2019-01-26

Applicant: NEC Laboratories America, Inc.

Inventor： Yaowen Li ,  Jian Fang ,  Ting Wang

IPC: G01M11/00 ,  G01H9/00

Abstract: Aspects of the present disclosure describe a multilayer coding method for physical value measurements in which a multi-pulse pattern is generated through several layers, each of which is encoded with a different cyclic codeword. The total coding gain is the product of the gains of each layer advantageously allowing a long cyclic codeword to be replaced by combining several short cyclic codewords. Of particular advantage, methods according to the present disclosure provide better signal-to-noise characteristics, longer sensing distances and lower computational complexity particularly suitable for high-performance and cost-effective distributed optical fiber sensing (DOFS).

公开(公告)号：US10574447B2

公开(公告)日：2020-02-25

申请号：US15897913

申请日：2018-02-15

Applicant: NEC Laboratories America, Inc.

Inventor： Ivan Djordjevic ,  Ting Wang ,  Shaoliang Zhang

IPC: H04L9/08 ,  H04B10/70 ,  H04J14/02 ,  H04B10/11 ,  H01Q3/26 ,  H01Q3/28 ,  H01Q3/38 ,  H04L27/34 ,  H04J14/04 ,  H04B10/516 ,  H01Q3/34 ,  H01Q21/00 ,  H04L27/36 ,  H04L27/38 ,  H04B7/0413 ,  H04B10/50

Abstract: Systems and methods for orbital angular momentum (OAM)-based multidimensional wireless communication. The OAM-based multidimensional wireless communication is preformed with a transmitter for generating an RF modulated signal carrying a data sequence. Further included is an OAM antenna array including OAM antenna elements, each of which includes an azimuthal phase shifter and an antenna element. The azimuthal phase shifter shifts an azimuthal phase term of a wavefront generated by the antenna element such that the OAM antenna element imposes the multidimensional modulated signal on a pre-determined OAM mode of a carrier signal corresponding to the azimuthal phase term.

公开(公告)号：US10476728B2

公开(公告)日：2019-11-12

申请号：US16153029

申请日：2018-10-05

Applicant: NEC Laboratories America, Inc.

Inventor： Shaoliang Zhang ,  Fatih Yaman ,  Ting Wang ,  Zhen Qu

IPC: H04B10/04 ,  H04L27/34 ,  H04B10/516 ,  H04L1/00 ,  H04B10/61 ,  H04B10/54

Abstract: Systems and methods for optical data transport, including controlling data transport across an optical transmission medium by generating two-dimensional (2D) distribution matchers (DMs) based on probabilistic fold shaping (PFS) and arbitrary probabilistic shaping (APS). The 2D PFS-based DM is can encode any N-fold rotationally symmetrical Quadrature Amplitude Modulation (QAM) format by applying the 2D PFS-based DM only to symbols in one quadrant based on a target entropy. A fold index yield uniform distribution is determined, and is utilized to carry generated uniform distributed parity check bits across the optical transmission medium. The 2D APS-based DM can encode any arbitrary modulation formats by encoding uniform binary data to generate non-uniform target symbols, and generating a probability distribution for the target symbols by indirectly applying the 2D APS-based DM based on a target probability distribution and a detected code rate of generated FEC code.

公开(公告)号：US10476599B2

公开(公告)日：2019-11-12

申请号：US15483587

申请日：2017-04-10

Applicant: NEC Laboratories America, Inc.

Inventor： Ting Wang ,  Ivan Djordjevic

IPC: H04B10/04 ,  H04B10/516 ,  H04B10/61 ,  H03M13/25 ,  H04J14/06 ,  H03M13/00 ,  H04B10/532 ,  H04B10/54 ,  H03M7/30

Abstract: A method for optical communication includes combining jointly source coding with LDPC channel coding into a nonuniform signalling by mapping low-complexity variable-length prefix codes onto a constellation; and performing arbitrary nonuniform signalling, where information bits and parity bits are transmitted with different modulation schemes.

公开(公告)号：US20190236477A1

公开(公告)日：2019-08-01

申请号：US16229676

申请日：2018-12-21

Applicant: NEC Laboratories America, Inc.

Inventor： Ming-Fang Huang ,  Ting Wang

IPC: G06N20/00 ,  G08G1/01 ,  H04B10/25 ,  G01H9/00 ,  G01M3/38

CPC classification number: G06N20/00 ,  G01H9/004 ,  G01M3/38 ,  G08G1/0116 ,  H04B10/25

Abstract: A fiber-based roadside condition sensing system is provided. The system includes a fiber optic cable arranged in various roadside locations for Distributed Vibration Sensing (DVS) and Distributed Acoustic Sensing (DAS) at the various roadside locations. The system further includes a machine-learning-based analyzer for selectively providing any of an early warning and a prevention of various detected conditions responsive to a machine-learning-based analysis of results from the DVS and the DAS.