Trellis based processing for robust digital multiband transmission

    公开(公告)号:US10680718B2

    公开(公告)日:2020-06-09

    申请号:US16293324

    申请日:2019-03-05

    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.

    Bit loading for optical discrete multi-tone transmission
    3.
    发明授权
    Bit loading for optical discrete multi-tone transmission 有权
    用于光学离散多音调传输的位加载

    公开(公告)号:US09350450B2

    公开(公告)日:2016-05-24

    申请号:US14252099

    申请日:2014-04-14

    Abstract: System and method embodiments are provided for bit loading for optical Discrete Multi-Tone Transmission (DMT). In an embodiment, a method for bit loading for optical DMT transmission or reception includes receiving, at a processor, a bit data stream, wherein the bit data stream comprises a plurality of subcarriers; assigning, with the processor, a code rate to each of a plurality of forward error correction (FEC) encoders/decoders according to a mapping of a signal-to-noise-ratio (SNR) to a code rate for each of the subcarriers or subcarrier groups, wherein each FEC encoder/decoder corresponds to a respective one of the subcarriers or a respective subcarrier group; and assigning, with the processor, a modulation format to each subcarrier or each subcarrier group according to a mapping of an SNR for each subcarrier or subcarrier group to a bit number for a corresponding subcarrier or subcarrier group.

    Abstract translation: 提供了用于光离散多音传输(DMT)的比特加载的系统和方法实施例。 在一个实施例中,用于光学DMT传输或接收的比特加载的方法包括在处理器处接收比特数据流,其中所述比特数据流包括多个子载波; 根据对每个子载波的信噪比(SNR)与码率的映射,将处理器分配给多个前向纠错(FEC)编码器/解码器中的每一个的码率,或者 子载波组,其中每个FEC编码器/解码器对应于子载波中的相应一个或相应的子载波组; 并且根据对于每个子载波组或子载波组的SNR对应于相应副载波组或子载波组的比特数,将处理器分配给每个子载波组或每个子载波组的调制格式。

    System and method for a multi-wavelength coherent receiver
    4.
    发明授权
    System and method for a multi-wavelength coherent receiver 有权
    用于多波长相干接收机的系统和方法

    公开(公告)号:US09225432B2

    公开(公告)日:2015-12-29

    申请号:US14175423

    申请日:2014-02-07

    CPC classification number: H04B10/6161 H04B10/614 H04B10/6162

    Abstract: Embodiments are provided for a novel multi-wavelength coherent receiver (MWCR) design and operation capable of detecting multiple optical wavelength channels. The embodiments include an optical receiver comprising a polarization-diversity optical hybrid module, a multiple wavelength local oscillator (MWLO) coupled to an input of the polarization-diversity optical hybrid module, a plurality of PIN diodes coupled to the polarization-diversity optical hybrid module, a plurality of analog-to-digital converters (ADCs) coupled to the PIN diodes, and a digital signal processing (DSP) module coupled to the ADCs. The polarization-diversity optical hybrid module splits an optical signal into multiple polarization components, wherein the optical signal includes multiple channels at multiple wavelengths. The MWLO locks the optical signal to the multiple wavelengths of the channels simultaneously. The DSP combines the signals from the ADCs corresponding to the polarization components and detects the channels at the wavelengths.

    Abstract translation: 提供实施例用于能够检测多个光波长信道的新型多波长相干接收机(MWCR)设计和操作。 这些实施例包括光接收器,其包括偏振分集光混合模块,耦合到偏振分集光混合模块的输入的多波长本地振荡器(MWLO),耦合到偏振分集光混合模块 耦合到PIN二极管的多个模数转换器(ADC)以及耦合到ADC的数字信号处理(DSP)模块。 偏振分集光混合模块将光信号分成多个偏振分量,其中光信号包括多个波长的多个通道。 MWLO同时将光信号锁定到通道的多个波长。 DSP组合来自对应于偏振分量的ADC的信号,并检测波长处的通道。

    Systems and methods for processing a subcarrier-multiplexed signal

    公开(公告)号:US11621794B1

    公开(公告)日:2023-04-04

    申请号:US17590243

    申请日:2022-02-01

    Inventor: Chuandong Li

    Abstract: The disclosed systems and methods for processing a subcarrier-multiplexed signal comprising: i) mixing the subcarrier-multiplexed signal with a local oscillator (LO) signal; ii) extracting a respective subcarrier signal from the subcarrier-multiplexed signal; iii) sampling the respective subcarrier signal; iv) extracting timing recovery information from the respective subcarrier signal; and v) processing the respective sampled subcarrier signal to extract data from the respective sampled subcarrier signal.

    Methods and apparatuses for controlling optical signals in optical networks

    公开(公告)号:US10673528B1

    公开(公告)日:2020-06-02

    申请号:US16284414

    申请日:2019-02-25

    Abstract: The disclosed systems, apparatuses and methods are directed to controlling optical channel signal and an optical network equipment in optical networks. The methods comprise adjusting an optical channel spectrum based on bit error rates (BER) measured for a dithered optical channel signal. The optical channel spectrum is dithered such that a signal reference frequency is alternated between a first second signal reference frequency and a second signal reference frequency. BER is measured and analysed separately for the dithered signal reference frequency being detuned to the first and to the second signal reference frequencies. Based on a BER difference between BER at the first signal reference frequency and BER at the second signal reference frequency, the optical channel spectrum is shifted with regards to frequency in order to improve optical network performance.

    Method and Apparatus for Robust Clock Recovery in Coherent Optical Systems

    公开(公告)号:US20180091288A1

    公开(公告)日:2018-03-29

    申请号:US15353394

    申请日:2016-11-16

    CPC classification number: H04L7/0075 H04B10/60

    Abstract: An optical channel between a coherent optical transmitter and a coherent optical receiver may include one or more components that act as a bandpass filter with a passband that is narrower than the signal bandwidth. Such a narrow filter may significantly attenuate the signal content close to the band edge of the data signal. As a result, timing error detection may work less effectively, and therefore clock recovery may be less effective or fail. Methods and systems are disclosed in which a single optical carrier is used to transmit a data signal that has multiple bands, and timing error detection is performed at the receiver using one or more inner bands of the multiple bands. The timing error detection may therefore be made more robust to the effects of the narrow filtering.

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