公开(公告)号：US10345138B2

公开(公告)日：2019-07-09

申请号：US15385972

申请日：2016-12-21

Applicant: NEC Laboratories America, Inc.

Inventor： Giovanni Milione ,  Philip Nan Ji ,  Ezra Ip ,  Ting Wang

IPC: G01H9/00

Abstract: A system to perform distributed acoustic sensing (DAS) in an environment with acoustic vibrations present includes at least an optical fiber positioned in said environment, wherein the optical fiber comprises N spatial channels and N laser pulses are launched into the N spatial channels of the optical fiber and propagate over a fiber length; and one or more sensors to measure N signals of acoustic vibration amplitude and frequency from each of N spatial channels, wherein the N signals are digitally added for spatial averaging and applied to determine DAS.

公开(公告)号：US20180102626A1

公开(公告)日：2018-04-12

申请号：US15724755

申请日：2017-10-04

Applicant: NEC Laboratories America, Inc.

Inventor： Ezra Ip ,  Yue-Kai Huang ,  Fatih Yaman ,  Shaoliang Zhang

IPC: H01S3/23 ,  H01S3/094 ,  H04B10/291 ,  H04B10/293

CPC classification number: H01S3/2316 ,  H01S3/06708 ,  H01S3/06737 ,  H01S3/06754 ,  H01S3/06758 ,  H01S3/094003 ,  H01S3/094011 ,  H01S3/094019 ,  H01S3/094053 ,  H01S3/1608 ,  H01S3/302 ,  H04B10/2912 ,  H04B10/2916 ,  H04B10/2935

Abstract: An unrepeatered transmission system includes a receiver coupled to a receive span; a transmitter coupled to the receive span; and a plurality of cascaded amplifiers in the receive span with dedicated fiber cores to supply one or more optical pumps from the receiver to each amplifier, wherein the plurality of cascaded amplifiers increase system reach by increasing the length of a back span in an unrepeatered link.

公开(公告)号：US09813158B2

公开(公告)日：2017-11-07

申请号：US15131307

申请日：2016-04-18

Applicant: NEC Laboratories America, Inc.

Inventor： Giovanni Milione ,  Ezra Ip ,  Ting Wang

IPC: H04B10/00 ,  H04B10/2581 ,  H04Q11/00 ,  H04B10/50 ,  H04B10/40 ,  H04B10/516 ,  H04J14/00

CPC classification number: H04B10/2581 ,  H04B10/40 ,  H04B10/503 ,  H04B10/516 ,  H04J14/00 ,  H04Q11/0005 ,  H04Q2011/0015

Abstract: Methods and system for transmitting data includes converting multiple optical beams to distinct respective spatial modes. Data is modulated onto each of the optical beams. The optical beams are combined into a single transmission beam. The transmission beam is launched onto a multimode optical fiber having an elliptical core.

公开(公告)号：US20150104192A1

公开(公告)日：2015-04-16

申请号：US14511560

申请日：2014-10-10

Applicant: NEC Laboratories America, Inc.

Inventor： Yue Kai Huang ,  Shaoliang Zhang ,  Ezra Ip

IPC: H04B10/524 ,  H04B10/54

CPC classification number: H04B10/541 ,  H04B10/676 ,  H04B2210/516

Abstract: An optical communication method includes converting an optical pulse amplitude modulation (PAM) signal to a square QAM signal using an optical delay interferometer (DI) to perform all-optical PAM to QAM conversion in the DI; performing optical de-correlation of I and Q tributaries of the QAM signal to avoid frequency dependent attenuation in RF cabling which impacts signal quality; and finding optimal phase control mechanism of the DI by monitoring and equalizing down-converted I and Q electrical signal amplitudes, using coherent detection; and emulating a square quadrature amplitude modulation (QAM) optical signal with duplicated data copies.

Abstract translation: 光通信方法包括使用光学延迟干涉仪（DI）将光脉冲幅度调制（PAM）信号转换为平方QAM信号，以在DI中执行全光PAM至QAM转换; 执行QAM信号的I和Q支路的光学去相关，以避免影响信号质量的RF布线中的频率相关衰减; 并通过监测和均衡下变频的I和Q电信号幅度，使用相干检测找到DI的最佳相位控制机制; 并仿真具有重复数据副本的正方形正交幅度调制（QAM）光信号。

公开(公告)号：US12206489B2

公开(公告)日：2025-01-21

申请号：US18109247

申请日：2023-02-13

Applicant: NEC Laboratories America, Inc.

Inventor： Yue-Kai Huang ,  Ezra Ip

IPC: H04J14/02

Abstract: Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously provide DFOS and WDM communications over amplified, multi-span optical WDM optical telecommunications facilities using all Raman amplification and coding schemes. Our all-Raman amplification operates stably—without isolators—and provides sufficient gain to compensate for fiber span loss for both DFOS signals and WDM channel signals—at the same time. Furthermore, our inventive techniques employ signal coding, such as MB-TGD-OFDR for DAS, and we operate our DFOS operation power at a much lower power level as compared to pulse interrogation techniques. With improved OSNR and reduced power using signal coding along with our distributed Raman amplification, our DFOS systems can co-exist with WDM communication channels on the same amplified multi-span fiber optic links over great distances.

公开(公告)号：US11920975B2

公开(公告)日：2024-03-05

申请号：US17314006

申请日：2021-05-06

Applicant: NEC Laboratories America, Inc.

Inventor： Ezra Ip ,  Yue-Kai Huang ,  Fatih Yaman ,  Shinsuke Fujisawa

IPC: G01H9/00 ,  H04B10/071 ,  H04Q11/00

CPC classification number: G01H9/004 ,  H04B10/071 ,  H04Q11/0005 ,  H04Q11/0067 ,  H04Q2011/0016 ,  H04Q2011/0083 ,  H04Q2213/13191

Abstract: Aspects of the present disclosure are directed to alternative repeater design(s) that advantageously improve signal-to-noise of distributed acoustic sensing (DAS) systems using coherent detection of Rayleigh backscatter in multi-span links including inline amplification that may be employed—for example—in undersea submarine systems. The repeater designs incorporate Rayleigh combine units (RCU) and Rayleigh drop units (RDU) to reduce Rayleigh backscatter loss as Rayleigh signal(s) is/are routed to a link that propagates the backscatter signal in an opposite direction relative to interrogation pulse(s).

公开(公告)号：US11461635B2

公开(公告)日：2022-10-04

申请号：US16153018

申请日：2018-10-05

Applicant: NEC Laboratories America, Inc.

Inventor： Yue-Kai Huang ,  Shaoliang Zhang ,  Ezra Ip ,  Weiyang Mo

IPC: G06N3/08 ,  H04B10/556 ,  G06N3/04 ,  H04B10/077 ,  H04B10/54

Abstract: Systems and methods for predicting performance of a modulation system are provided. A neural network model is trained using performance information of a source system. The neural network model is modified with transferable knowledge about a target system to be evaluated. The neural network model is tuned using specific characteristics of the target system to create a source-based target model. The target system performance is evaluated using the source-based target model to predict system performance of the target system.

公开(公告)号：US11296786B2

公开(公告)日：2022-04-05

申请号：US17221837

申请日：2021-04-04

Applicant: NEC Laboratories America, Inc.

Inventor： Yue-Kai Huang ,  Ezra Ip ,  Fatih Yaman

IPC: H04B10/07 ,  H04B10/079 ,  H04B10/294 ,  H04B10/69 ,  G02B6/02 ,  G01M11/00 ,  H04B10/071 ,  H04J14/02

Abstract: Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously overcome problems encountered when operating DFOS systems over operational telecommunications facilities namely, cross-phase modulation, and uneven amplitude profiles through the use of a novel constant amplitude coded DFOS employing out-of-band signaling.

公开(公告)号：US11193801B2

公开(公告)日：2021-12-07

申请号：US16879670

申请日：2020-05-20

Applicant: NEC Laboratories America, Inc.

Inventor： Ezra Ip ,  Yue-Kai Huang

IPC: G01D5/353 ,  G01L1/24 ,  G01K11/32 ,  G01M11/00 ,  G01K11/322

Abstract: Aspects of the present disclosure describe amplifier dynamics compensation through feedback control for distributed fiber sensing systems, methods, and structures employing Brillouin optical time-domain reflectometry.

公开(公告)号：US11133865B2

公开(公告)日：2021-09-28

申请号：US17106143

申请日：2020-11-29

Applicant: NEC Laboratories America, Inc.

Inventor： Yue-Kai Huang ,  Shaoliang Zhang ,  Ezra Ip ,  Jiakai Yu

IPC: H04B10/079 ,  G06N3/04 ,  H04L27/34 ,  H04B10/07

Abstract: Aspects of the present disclosure describe systems, methods. and structures in which a hybrid neural network combining a CNN and several ANNs are shown useful for predicting G-ONSR for Ps-256QAM raw data in deployed SSMF metro networks with 0.27 dB RMSE. As demonstrated, the CNN classifier is trained with 80.96% testing accuracy to identify channel shaping factor. Several ANN regression models are trained to estimate G-OSNR with 0.2 dB for channels with various constellation shaping. Further aspects include the tuning of existing optical networks and the characterization of retrofit/upgraded optical networks to estimate capacity—both aspects employing our inventive hybrid neural network methodology.