公开(公告)号：US11863361B1

公开(公告)日：2024-01-02

申请号：US18082089

申请日：2022-12-15

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Meng Qiu ,  Xuefeng Tang ,  Ahmed Mohamed Medra ,  Hossein Najafi ,  Ali Bakhshali

IPC: H04B1/00 ,  H04L27/12 ,  H04L27/152

CPC classification number: H04L27/127 ,  H04L27/152

Abstract: The disclosed systems and methods for frequency domain (FD) local oscillator frequency offset (LOFO) compensation. The method comprising: i) compensating, by an integer Fast Fourier Transform (FFT) bins-based oscillator, LOFO in a received signal by an integer number of FFT bins; and ii) compensating, by a fractional FFT bins-based oscillator, LOFO in the compensated signal by the integer FFT bins-based oscillator with a fine compensation resolution of a fractional number of FFT bins.

公开(公告)号：US20190199443A1

公开(公告)日：2019-06-27

申请号：US16293324

申请日：2019-03-05

Applicant: Huawei Technologies Co., Ltd.

Inventor： Mahdi Zamani ,  Jeebak Mitra ,  Hossein Najafi ,  Zhuhong Zhang ,  Chuandong Li

IPC: H04B10/61

CPC classification number: H04B10/616 ,  H04B10/548 ,  H04B10/5561 ,  H04B10/613 ,  H04B10/614

Abstract: Aspects of the present disclosure are directed in part to a receiver DSP unit including an equalization module. The equalization module includes a trellis-based equalization module that may utilize multiple trellis-based processors (TBP), which can each be individually adaptively configured for performing a trellis-based equalization. The design of the TBPs allows them to be configured for compensating a residual Inter-Symbol Interference (ISI) as well as compensating a residual Phase Noise (PN). ISI is an example of an additive impairment and PN is an example of a multiplicative impairment that communication systems, particularly high speed transmission systems such as coherent optical systems, can suffer from.

公开(公告)号：US11770276B1

公开(公告)日：2023-09-26

申请号：US17962060

申请日：2022-10-07

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Ahmed Mohamed Medra ,  Hossein Najafi ,  Ali Bakhshali ,  Jin Wang ,  Chuandong Li ,  Zhuhong Zhang

IPC: H04L25/03 ,  H04B7/10

CPC classification number: H04L25/03057 ,  H04B7/10

Abstract: The disclosed systems and methods for compensating the polarization dependent loss (PDL) in communication networks comprising: i) filtering, by a first feed-forward filter, a current set of symbols in an equalized X-Pol signal; ii) filtering, by a second feed-forward filter, a current set of symbols in an equalized Y-Pol signal; iii) filtering, by a first feed-backward filter, a previously decided set of symbols associated with the equalized X-Pol signal; iv) filtering, by a second feed-backward filter a previously decided set of symbols associated with the equalized Y-Pol signal; v) adding, by a first adder, the outputs from the first feed-forward filter and the second feed-forward filter; and vi) subtracting, by the first adder, the outputs from the first feed-backward filter and the second feed-backward filter from the addition of outputs from the first feed-forward filter and the second feed-forward filter to determine the symbols in the equalized X-Pol signal.

公开(公告)号：US11153139B1

公开(公告)日：2021-10-19

申请号：US17158577

申请日：2021-01-26

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Ahmed Mohamed Medra ,  Hossein Najafi ,  Zhuhong Zhang

IPC: H04L27/10 ,  H04L27/26 ,  H04L25/03 ,  H04L1/00

Abstract: The disclosed systems and methods are directed to transmitting and receiving symbols. In particular, splitting, a symbol dataset into symbol subsets, modulating, the symbol subsets using different sub-carriers, roll off factors and time acceleration factors, performing frequency shifting and combining the frequency shifted and modulated symbol subsets to generate a digital multiband (DMB) signal, transmitting and receiving the DMB signal, down converting the received DMB signal into a plurality of baseband signals, segregating the plurality of baseband signals in accordance with a manner by which the symbol subsets have been processed before transmission, forwarding a first portion of the plurality of baseband signals to a minimum mean square error (MMSE) based receiver, forwarding a second portion of the plurality of baseband signals to a matched filter-based receiver, and combining the output of the MMSE based receiver and matched filter-based receiver to generate an equivalent symbol dataset.

公开(公告)号：US10680718B2

公开(公告)日：2020-06-09

申请号：US16293324

申请日：2019-03-05

Applicant: Huawei Technologies Co., Ltd.

Inventor： Mahdi Zamani ,  Jeebak Mitra ,  Hossein Najafi ,  Zhuhong Zhang ,  Chuandong Li

IPC: H04B10/548 ,  H04B10/61 ,  H04B10/556

Abstract: Aspects of the present disclosure are directed in part to a receiver DSP unit including an equalization module. The equalization module includes a trellis-based equalization module that may utilize multiple trellis-based processors (TBP), which can each be individually adaptively configured for performing a trellis-based equalization. The design of the TBPs allows them to be configured for compensating a residual Inter-Symbol Interference (ISI) as well as compensating a residual Phase Noise (PN). ISI is an example of an additive impairment and PN is an example of a multiplicative impairment that communication systems, particularly high speed transmission systems such as coherent optical systems, can suffer from.