公开(公告)号：US20210091740A1

公开(公告)日：2021-03-25

申请号：US16771688

申请日：2018-02-27

申请人： XIAMEN UX HIGH-SPEED IC CO., LTD.

发明人： Shaoheng Lin

IPC分类号： H03G3/30 ,  H04B10/25 ,  H04B10/69

摘要： Provided in the present invention is an automatic gain control method for a burst-mode transimpedance amplifier. A transistor is connected in parallel at either end of a feedback resistor of a transimpedance amplifier. A gate-source voltage of the transistor is controlled by detecting and then reversely amplifying an output voltage of the transimpedance amplifier. The present invention also provides a circuit implementing the method, obviates the need for support from any particular process, and is implementable using conventional components.

公开(公告)号：US10958352B2

公开(公告)日：2021-03-23

申请号：US16517214

申请日：2019-07-19

申请人： HUAWEI TECHNOLOGIES CO., LTD.

发明人： Yuanda Huang ,  Liangchuan Li

IPC分类号： H04B10/516 ,  H04B7/216 ,  H04B10/69 ,  H04B10/50 ,  H04L27/34 ,  H04B10/54 ,  H04J14/00 ,  H04B1/7087 ,  H04B10/2507 ,  H04L27/36 ,  H04B10/2569

摘要： According to a signal transmitting method, a signal receiving method, and a related device and system, a generated single-wavelength optical carrier may be split into N subcarriers with a same wavelength by using a splitting device, corresponding data modulation and corresponding amplitude spread spectrum modulation are performed on the N subcarriers by using N spreading codes and N low-speed data signals obtained by deserializing a received high-speed data signal, to obtain N spread spectrum modulation signals, and the N spread spectrum modulation signals are combined and output. A multicarrier generation apparatus or the like having a relatively complex structure does not need to be used for optical carrier splitting, and spectrum spreading does not need to be performed in a phase modulation manner in which a plurality of delay units or controllable phase units are required.

公开(公告)号：US10958345B1

公开(公告)日：2021-03-23

申请号：US16869265

申请日：2020-05-07

申请人： CABLE TELEVISION LABORATORIES, INC.

发明人： Mu Xu ,  Zhensheng Jia ,  Junwen Zhang ,  Haipeng Zhang ,  Luis Alberto Campos

IPC分类号： H04B10/2507 ,  H04B10/69 ,  H04Q11/00 ,  H04B10/40

摘要： An echo cancellation method includes steps of (a) extracting phase-distortion estimates, (b) reconstructing an echo signal, (c) generating a clean signal, and (d) producing a primary signal. Step (a) includes extracting, from a first phase signal, a plurality of phase-distortion estimates, the first phase signal having been estimated from an echo-corrupted signal received at a first coherent transceiver of a coherent optical network. Step (b) includes reconstructing an echo signal from the plurality of phase-distortion estimates and a transmitted signal transmitted by the first coherent transceiver. Step (c) includes generating a clean signal as a difference between the reconstructed echo signal and the first phase signal. Step (d) includes producing a primary signal by mapping each of a plurality of clean-phase estimates of the clean signal to one of a plurality of constellation symbols associated with a modulation scheme of the primary signal.

公开(公告)号：US20210083774A1

公开(公告)日：2021-03-18

申请号：US17103180

申请日：2020-11-24

申请人： HUAWEI TECHNOLOGIES CO., LTD.

发明人： Wei SU ,  Qiuyou WU ,  Huaping QING

IPC分类号： H04B10/27 ,  H04B10/69 ,  H04L1/00 ,  H04J3/16

摘要： This application provides data transmission methods and apparatuses. One method includes: processing, by a network device, a first optical data unit (ODU) to obtain a second ODU, wherein a bit rate of the second ODU is lower than a bit rate of the first ODU; and sending, by the network device, the second ODU.

公开(公告)号：US20210083767A1

公开(公告)日：2021-03-18

申请号：US16756752

申请日：2017-12-25

申请人： Accelink Technologies Co., Ltd.

发明人： Peng Zhang ,  Jiantao Zhang ,  Cuihong Zhang

IPC分类号： H04B10/071 ,  H04B10/079 ,  H04B10/69 ,  H04B10/50

摘要： The present disclosure relates to a signal processing system applied to remove OTDR noise, comprising: an analog-to-digital converter, a laser and driving unit, a sequence accumulator, a preprocessing counter, a pulse generator, a dual-port memory, a self-adaptive filter, an event decision device, and a preprocessing data decision device. The self-adaptive filter reads preprocessing data from a read-only port of the dual-port memory, and performs noise processing on the read preprocessing data by using a self-adaptive filtering method of wavelet transform. The event decision device performs an event decision on the filtered data output from the self-adaptive filter; The preprocessing data decision device decides whether a certain set of preprocessing data in m groups of preprocessing data is correct data or high-signal-to-noise data according to the difference of the m groups of preprocessing data after passing through the event decision device.

公开(公告)号：US20210075516A1

公开(公告)日：2021-03-11

申请号：US16951653

申请日：2020-11-18

申请人： INPHI CORPORATION

发明人： Benjamin P. SMITH ,  Jamal RIANI ,  Sudeep BHOJA ,  Arash FARHOODFAR ,  Vipul BHATT

IPC分类号： H04B10/58 ,  H04B10/2507 ,  H04B10/69 ,  H04B10/54 ,  H04B10/516 ,  H04B10/00

摘要： A circuit and method for mitigating multi-path interference in direct detection optical systems is provided. Samples of an optical signal having a pulse amplitude modulated (PAM) E-field are processed by generating a PAM level for each sample. For each sample, the sample is subtracted from the respective PAM level to generate a corresponding error sample. The error samples are lowpass filtered to produce estimates of multi-path interference (MPI). For each sample, one of the estimates of MPI is combined with the sample to produce an interference-mitigated sample.

公开(公告)号：US20210075515A1

公开(公告)日：2021-03-11

申请号：US17014856

申请日：2020-09-08

申请人： FUJITSU LIMITED

发明人： KAZUMASA MIKAMI ,  Junichi Sugiyama

IPC分类号： H04B10/516 ,  H04L1/00 ,  H04B10/69

摘要： An optical communication system includes a first communication device configured to transmit optical signals, and a second communication device configured to receive the optical signals. The first transmission device includes encoding circuit that configured to assign, to a plurality of bit strings, symbols each corresponding to a value of every one of the plurality of bit strings, the symbols being among a plurality of symbols in a constellation of a multi-level modulation scheme, convert values of bit strings, generate the second error correction code from a second bit string among the plurality of bit strings in every one of a plurality of periods, delay the first error correction code, and delay the second error correction code, wherein the encoding circuit uses the delayed first error correction code and the delayed second error correction code to convert a value of the second bit string.

公开(公告)号：US20210067256A1

公开(公告)日：2021-03-04

申请号：US16949355

申请日：2020-10-27

申请人： INTERNATIONAL BUSINESS MACHINES CORPORATION

发明人： Mohit Kapur ,  Muir Kumph

IPC分类号： H04B17/20 ,  G01R31/28 ,  H04B10/25 ,  H04B1/04 ,  H04B1/26 ,  H04B10/2507 ,  H04B10/69 ,  H04B15/00

摘要： Embodiments include techniques for transmitting and receiving radio frequency (RF) signals, where the techniques for generating, via a digital analog converter (DAC), a frequency signal, and filtering the frequency signal to produce a first filtered signal and a second filtered signal. The techniques also include transmitting the second filtered signal to a device under test and filtering the second filtered signal into a sub-signal having one or more components. The techniques include mixing the first filtered signal with the sub-signal to produce a first mixed signal, subsequently mixing the first mixed signal with an output signal received from the device under test to produce a second mixed signal and converting the second mixed signal for analysis.

公开(公告)号：US20210067246A1

公开(公告)日：2021-03-04

申请号：US16556881

申请日：2019-08-30

申请人： CACI, Inc. - Federal

发明人： Gerald NYKOLAK ,  Andrew Russell Grant ,  David C. Nielsen

IPC分类号： H04B10/11 ,  H04B10/25 ,  H04B10/50 ,  H04B10/69

摘要： Methods, devices, and systems are described for free space optical communication. An example device can comprise a laser, a modulator configured to cause the laser to output an optical signal comprising a data signal and a beacon signal, a defocuser optically coupled to the laser and configured to receive the optical signal and control a beam divergence of the optical signal, an optical interface configured to receive the optical signal from the defocuser and output the optical signal into free space, and a controller configured to cause the defocuser to adjust the beam divergence based on an operational mode of the laser.

公开(公告)号：US10924186B1

公开(公告)日：2021-02-16

申请号：US16701475

申请日：2019-12-03

申请人： NETGAMI SYSTEM L.L.C.

发明人： John Lynn ,  Eric Lynn

IPC分类号： H04B10/00 ,  H04B10/25 ,  G02B6/42 ,  H04B10/80 ,  H04B10/69 ,  H04B10/50

摘要： An optical fiber link includes a local host control device including a microcontroller unit transmitting a host transmitting signal, and an electrical-to-optical converter converting the host transmitting signal to a laser beam optical signal; a remote sensor device including a sensor device transmitting a sensor transmitting signal and an optical return module selectively passing or blocking part of the laser beam optical signal; and a fiber cable including an upstream fiber link and a downstream fiber link and establishing communications between the local host control device and the remote sensor device, the laser beam optical signal being delivered from the local host control device to the remote sensor device through the downstream fiber link. The optical return module selectively passes or blocks the part of the laser beam optical signal delivered by the downstream fiber link based on the sensor transmitting signal to the upstream fiber link.