公开(公告)号：US11677540B1

公开(公告)日：2023-06-13

申请号：US17161169

申请日：2021-01-28

Applicant: CABLE TELEVISION LABORATORIES, INC.

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

IPC: H04L7/04 ,  H04J3/06 ,  H04L7/00 ,  H04B3/54 ,  H04L27/36

CPC classification number: H04L7/042 ,  H04B3/542 ,  H04J3/0638 ,  H04L7/0075 ,  H04L27/365

Abstract: A method for synchronizing a data frame and data symbols in a communication system includes generating a training sequence including a serial sequence of data symbols that are conjugate symmetric, inserting the training sequence in a transmitter-side data frame, converting constituent data symbols of the transmitter-side data frame to communication signals, transmitting the communication signals from a transmitter to a receiver, converting the communication signals to a stream of received data symbols, detecting presence of the training sequence in the stream of received data symbols, and identifying a position of a received data frame from the presence of the training sequence.

公开(公告)号：US11646813B1

公开(公告)日：2023-05-09

申请号：US17409878

申请日：2021-08-24

Applicant: CABLE TELEVISION LABORATORIES, INC.

Inventor： Zhensheng Jia ,  Junwen Zhang ,  Mu Xu ,  Haipeng Zhang ,  Luis Alberto Campos ,  Curtis Dean Knittle

IPC: H04B10/61 ,  H04J14/06 ,  H04B10/67

CPC classification number: H04J14/06 ,  H04B10/612 ,  H04B10/6162 ,  H04B10/677

Abstract: A digital receiver is configured to process a polarization multiplexed carrier from a communication network. The polarization multiplexed carrier includes a first polarization and a second polarization. The receiver includes a first lane for transporting a first input signal of the first polarization, a second lane for transporting a second input signal of the second polarization, a dynamic phase noise estimation unit disposed within the first lane and configured to determine a phase noise estimate of the first input signal, a first carrier phase recovery portion configured to remove carrier phase noise from the first polarization based on a combination of the first input signal and a function of the determined phase noise estimate, and a second carrier phase recovery portion configured to remove carrier phase noise from the second polarization based on a combination of the second input signal and the function of the determined phase noise estimate.

公开(公告)号：US11641293B1

公开(公告)日：2023-05-02

申请号：US17228643

申请日：2021-04-12

Applicant: CABLE TELEVISION LABORATORIES, INC.

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

IPC: H04L25/03

Abstract: A method and apparatus of distortion compensation during data transmission uses an interweaved look-up table (ILUT) to mitigate residual signal distortions in a signal transmitted over a transmission link. The ILUT interweaves states across both an I and a Q tributary to calculate mean error and an extended symbol basis. As a result, the method works particularly well against two-dimensional distortions like nonlinearity, IQ-imbalance, and quadrature error. The method may be used for either pre-compensation when it is combined with k-means clustering in a transmitter or post-compensation when it is combined with maximum likelihood (ML) detection in a receiver.

公开(公告)号：US11489594B2

公开(公告)日：2022-11-01

申请号：US16983786

申请日：2020-08-03

Applicant: CABLE TELEVISION LABORATORIES, INC

Inventor： Zhensheng Jia ,  Luis Alberto Campos ,  Jing Wang ,  Mu Xu ,  Haipeng Zhang ,  Curtis Dean Knittle

IPC: H04B10/25 ,  H04L12/28 ,  H04B10/40

Abstract: A full duplex communication network includes an optical transmitter end having a first coherent optics transceiver, an optical receiver end having a second coherent optics transceiver, and an optical transport medium operably coupling the first coherent optics transceiver to the second coherent optics transceiver. The first coherent optics transceiver is configured to (i) transmit a downstream optical signal at a first wavelength, and (ii) simultaneously receive an upstream optical signal at a second wavelength. The second coherent optics transceiver is configured to (i) receive the downstream optical signal, and (ii) simultaneously transmit the upstream optical signal. The first wavelength has a first center frequency separated from a second center frequency of the second wavelength.

公开(公告)号：US11418263B2

公开(公告)日：2022-08-16

申请号：US16855921

申请日：2020-04-22

Applicant: CABLE TELEVISION LABORATORIES, INC

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

IPC: H04B10/50 ,  G02F1/21 ,  G02B27/28 ,  H01S5/32 ,  H04B10/516 ,  H04B10/25 ,  H01S5/323

Abstract: An optical full-field transmitter for an optical communications network includes a primary laser source configured to provide a narrow spectral linewidth for a primary laser signal, and a first intensity modulator in communication with a first amplitude data source. The first intensity modulator is configured to output a first amplitude-modulated optical signal from the laser signal. The transmitter further includes a first phase modulator in communication with a first phase data source and the first amplitude-modulated optical signal. The first phase modulator is configured to output a first two-stage full-field optical signal. The primary laser source has a structure based on a III-V compound semiconductor.

公开(公告)号：US11265099B1

公开(公告)日：2022-03-01

申请号：US16877439

申请日：2020-05-18

Applicant: CABLE TELEVISION LABORATORIES, INC

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

IPC: H04J14/00 ,  H04J14/02

Abstract: A coherent passive optical network includes a downstream transceiver and first and second upstream transceivers in communication with an optical transport medium. The downstream transceiver includes a downstream processor for mapping a downstream data stream to a plurality of sub-bands, and a downstream transmitter for transmitting a downstream optical signal modulated with the plurality of sub-bands. The first upstream transceiver includes a first local oscillator (LO) for tuning a first LO center frequency to a first sub-band of the plurality of sub-bands, and a first downstream receiver for coherently detecting the downstream optical signal within the first sub-band. The second upstream transceiver includes a second downstream receiver configured for coherently detecting the downstream optical signal within a second sub-band of the plurality of sub-bands. The downstream processor dynamically allocates the first and second sub-bands to the first and second transceivers in the time and frequency domains.

公开(公告)号：US11223504B2

公开(公告)日：2022-01-11

申请号：US16866398

申请日：2020-05-04

Applicant: CABLE TELEVISION LABORATORIES, INC

Inventor： Mu Xu ,  Zhensheng Jia ,  Peng-Chun Peng ,  Siming Liu ,  Feng Lu ,  Curtis Dean Knittle

IPC: H04B1/38 ,  H04L25/03 ,  H04B10/54 ,  H04B10/50 ,  H04L25/06 ,  H04B10/69

Abstract: An optical network includes a transmitter portion configured to (i) precode an input digitized stream of symbols into a precoded symbol stream, (ii) pulse shape the precoded symbol stream with an eigenvalue channel matrix, and (iii) transmit the pulse shaped symbol stream over a digital optical link. The optical network further includes a receiver portion configured to (i) recover the pulse shaped symbol stream from the digital optical link, (ii) decompose eigenvalues of the eigenvalue channel matrix from the recovered symbol stream, and (iii) decode the decomposed symbol stream into an output symbol stream.

公开(公告)号：US11223421B1

公开(公告)日：2022-01-11

申请号：US17166611

申请日：2021-02-03

Applicant: CABLE TELEVISION LABORATORIES, INC.

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

IPC: H04B10/00 ,  H04B10/2507 ,  H04B10/58

Abstract: A skew compensation system for a coherent optical communication network includes a transmitter and a receiver in operable communication with an optical transport medium of a coherent optical network. The transmitter includes a first transmitter-side tunable delay line configured to delay transmission of a first signal by a first skew amount, thereby producing a pre-compensated first signal. The receiver includes a first receiver-side tunable delay line configured to delay transmission of the pre-compensated first signal to a digital signal processor (DSP) of the receiver by a second skew amount, thereby producing a final signal that is both pre-compensated and post-compensated (i.e., fully compensated).

公开(公告)号：US11146351B1

公开(公告)日：2021-10-12

申请号：US17008548

申请日：2020-08-31

Applicant: CABLE TELEVISION LABORATORIES, INC

Inventor： Mu Xu ,  Ruoyu Sun ,  Balkan Kecicioglu ,  Junwen Zhang ,  Haipeng Zhang ,  Zhensheng Jia ,  Luis Alberto Campos

IPC: H04J14/02 ,  H04Q11/00 ,  H04B10/11 ,  H04B10/2575

Abstract: A communications network includes a central communication unit, an optical transport medium, and a plurality of remote radio base stations. The central communication unit generates, within a selected millimeter-wave frequency band, a plurality of adjacent two-tone optical frequency conjugate pairs. Each conjugate pair includes a first optical tone carrying a modulated data signal, and a second optical tone carrying a reference local oscillator signal. The optical transport medium transports the plurality of two-tone conjugate pairs to the plurality of radio base stations, and each base station receives at least one conjugate pair at an optical front end thereof. The optical front end separates the first optical tone from the second optical tone, and converts the first optical tone into a millimeter-wave radio frequency electrical signal. The base station further includes a radio antenna system for wirelessly transmitting the millimeter-wave radio frequency electrical signal to at least one wireless receiving device.

公开(公告)号：US11146338B2

公开(公告)日：2021-10-12

申请号：US16510486

申请日：2019-07-12

Applicant: CABLE TELEVISION LABORATORIES, INC.

Inventor： Mu Xu ,  Zhensheng Jia

IPC: H04B10/06 ,  H04B10/61 ,  H04B10/2575 ,  H04L1/00

Abstract: Methods, systems, and devices for a decision directed multi-modulus searching algorithm are described. A receiver may receive an optical signal including a set of data symbols. The receiver may iteratively determine a set of centroids for demodulating the set of data symbols (e.g., as part of a training procedure). The centroids may be used to demodulate the set of data symbols according to a modulation constellation associated with the set of data symbols. The training procedure may include, for each data symbol of a subset of data symbols, assigning a centroid of the set of centroids to each data symbol and updating the set of centroids based on assigning the centroid to each data symbol. The receiver may demodulate the set of data symbols based on the updated set of centroids.