公开(公告)号：EP2798766B1

公开(公告)日：2018-06-13

申请号：EP12808847.3

申请日：2012-12-28

Applicant: Xieon Networks S.à r.l.

Inventor： CALABRO, Stefano ,  HEBEBRAND, Christina ,  ROSENKRANZ, Werner ,  SPINNLER, Bernhard

IPC: H04L7/027

CPC classification number: H04J14/06 ,  H04B10/61 ,  H04B10/614 ,  H04B10/6165 ,  H04B10/6166 ,  H04L7/027 ,  H04L25/03044 ,  H04L25/03891 ,  H04L27/2662 ,  H04L27/2672 ,  H04L27/2697

Abstract: A received POLMUX signal is rotated by fixed rotation parameters (Rot0, Rot1, Rot2) and the rotated POLMUX signal with optimal signal performance is selected and phase information is derived from both polarities. A pre-filter improves the timing accuracy.

公开(公告)号：EP3272039A1

公开(公告)日：2018-01-24

申请号：EP16714030.0

申请日：2016-03-09

Applicant: Mitsubishi Electric Corporation

Inventor： MILLAR, David, S. ,  AKINO, Toshiaki ,  PAJOVIC, Milutin

IPC: H04B10/61 ,  H04L25/03 ,  H04B1/707

CPC classification number: H04B10/6971 ,  H04B10/0795 ,  H04B10/612 ,  H04B10/6165 ,  H04B10/6972 ,  H04L1/0036 ,  H04L25/03019

Abstract: A method decodes an optical signal transmitted over an optical channel from a transmitter to a receiver. The receiver receives the transmitted optical signal to produce a digital signal including data symbols and pilot symbols, and determines filtering coefficients based on an error between amplitudes of the received pilot symbols and amplitudes of transmitted pilot symbols, while ignoring errors between phases of the received pilot symbols and phases of the transmitted pilot symbols. The amplitudes and the phases of the transmitted pilot symbols are known at the transmitter and the receiver. The receiver filters the digital signal according to the filtering coefficients to produce a filtered signal with equalized amplitude and an unconstrained phase demodulates and decodes the filtered signal to produce an estimate of the transmitted optical signal.

公开(公告)号：EP3241290A1

公开(公告)日：2017-11-08

申请号：EP16739724.9

申请日：2016-01-05

Applicant: Huawei Technologies Co., Ltd.

Inventor： ZAMANI, Mahdi ,  ZHANG, Zhuhong ,  LI, Chuandong

IPC: H04B7/204

CPC classification number: H04L25/024 ,  H04B10/6164 ,  H04B10/6165 ,  H04L27/0014 ,  H04L27/2271 ,  H04L27/3827 ,  H04L2027/0038 ,  H04L2027/0057 ,  H04L2027/0085

Abstract: The present disclosure provides a method and system for fine estimation of a local oscillator frequency offset of a received signal at a coherent receiver, by evaluating the probability mass function (PMF) of the signal phase of output symbols at different frequencies. At frequencies other than the actual frequency offset, the signal phase is uniformly distributed in [−π,π] such that the summation of a function of PMF values where the function is convex or concave between 0 and 1 can be utilized to determine an a frequency offset to be used by the coherent receiver.

公开(公告)号：EP3016339B1

公开(公告)日：2017-09-13

申请号：EP13889762.4

申请日：2013-07-15

Applicant: Huawei Technologies Co., Ltd.

Inventor： LIU, Ling ,  LI, Liangchuan

IPC: H04L27/227 ,  H04L27/38 ,  H04L27/00

CPC classification number: H04L27/0014 ,  H04B10/6165 ,  H04L27/3827 ,  H04L2027/0046 ,  H04L2027/0067 ,  H04L2027/0095

公开(公告)号：EP2343841B1

公开(公告)日：2017-08-23

申请号：EP10197368.3

申请日：2010-12-30

Applicant: FUJITSU LIMITED

Inventor： Nakashima, Hisao ,  Hoshida, Takeshi

IPC: H04B10/61 ,  H04B10/69

CPC classification number: H04B10/6165 ,  H04B10/6161 ,  H04B10/6162 ,  H04B10/6164 ,  H04B10/697 ,  H04L7/0335

公开(公告)号：EP2677673A4

公开(公告)日：2017-07-05

申请号：EP12746861

申请日：2012-02-16

Applicant: NEC CORP

Inventor： OGASAHARA DAISAKU

IPC: H04B10/61 ,  H04J14/06

CPC classification number: H04B10/6162 ,  H04B10/614 ,  H04B10/6164 ,  H04B10/6165 ,  H04B10/6166 ,  H04J14/06

公开(公告)号：EP2672636A4

公开(公告)日：2017-07-05

申请号：EP11857687

申请日：2011-09-02

Applicant: NEC CORP

Inventor： ABE JUNICHI ,  YASUDA WAKAKO ,  FUKUCHI KIYOSHI

IPC: H04B10/60 ,  H04B10/077 ,  H04B10/50 ,  H04B10/61

CPC classification number: H04B10/616 ,  H04B10/0775 ,  H04B10/6164 ,  H04B10/6165

Abstract: In a coherent optical receiver, sufficient demodulation becomes impossible and consequently receiving performance deteriorates if an inter-channel skew arises, therefore, a coherent optical receiver according to an exemplary aspect of the invention includes a local light source, a 90° hybrid circuit, an optoelectronic converter, an analog to digital converter, and a digital signal processing unit; wherein the 90° hybrid circuit makes multiplexed signal light interfere with local light from the local light source, and outputs a plurality of optical signals separated into a plurality of signal components; the optoelectronic converter detects the optical signals and outputs detected electrical signals; the analog to digital converter quantizes the detected electrical signals and outputs quantized signals; the digital signal processing unit includes a skew compensation unit for compensating a difference in propagation delay between the plurality of signal components, and an FFT operation unit for performing a fast Fourier transform process on the quantized signals; and wherein the difference in propagation delay is calculated on the basis of a plurality of peak values with a central focus on one peak value in the results of performing the fast Fourier transform process.

Abstract translation: 在相干光接收机中，如果出现信道间偏斜，则足够的解调变得不可能，并且因此接收性能恶化，因此，根据本发明示例性方面的相干光接收机包括局部光源，90°混合电路， 光电转换器，模数转换器和数字信号处理单元; 其中所述90°混合电路使得多路复用信号光与来自所述本地光源的本地光发生干涉，并输出分离成多个信号分量的多个光信号; 光电转换器检测光信号并输出​​检测到的电信号; 模数转换器量化检测到的电信号并输出​​量化的信号; 数字信号处理单元包括用于补偿多个信号分量之间的传播延迟差的偏斜补偿单元以及用于对量化的信号执行快速傅立叶变换处理的FFT运算单元; 并且其中基于在执行所述快速傅立叶变换处理的结果中的中心聚焦在一个峰值上的多个峰值来计算所述传播延迟的差异。

公开(公告)号：EP3048746A1

公开(公告)日：2016-07-27

申请号：EP14797641.9

申请日：2014-05-23

Applicant: ZTE Corporation ,  ZTE Microelectronics Technology Co., Ltd.

Inventor： YAO, Yangzhong ,  LI, Qiang ,  LI, Yunpeng ,  GU, Guohua ,  REN, Wei

IPC: H04B10/079

CPC classification number: H04B10/07951 ,  H04B10/612 ,  H04B10/613 ,  H04B10/6161 ,  H04B10/6163 ,  H04B10/6165 ,  H04B10/6166

Abstract: Disclosed are a chromatic dispersion estimation method and device in optical coherent communication, wherein, the method includes: performing a fast Fourier transform on IQ-imbalance compensated data to obtain frequency-domain data in two polarization directions; calculating autocorrelation sequences of the frequency-domain data and performing an inverse fast Fourier transform on the values of the autocorrelation sequences; calculating modulus squares of the results of the inverse fast Fourier transform, and adding the results in the two polarization directions to obtain P [n]; determining a mean value P [n] of P [n]s of a plurality of data sets; calculating an index n 0 of the maximum value of P̃ [n], and estimating a dispersion value of the optical fiber link according to the index n 0 of the maximum value of P̃ [n]. The abovementioned technical solution allows a significantly accurate and rapid estimation of dispersion values.

Abstract translation: 本发明公开了一种光相干通信中的色散估计方法及装置，其中，该方法包括：对IQ不平衡补偿后的数据进行快速傅立叶变换，得到两个极化方向的频域数据; 计算频域数据的自相关序列并对自相关序列的值执行逆快速傅里叶变换; 计算快速傅立叶逆变换结果的模数平方，并将结果在两个偏振方向上相加得到P [n]; 确定多个数据集的P [n]的平均值P [n]; 计算P [n]的最大值的索引n0，并根据最大值P [n]的索引n0估计光纤链路的色散值。 上述技术方案允许对色散值进行非常准确且快速的估计。

公开(公告)号：EP3043491A1

公开(公告)日：2016-07-13

申请号：EP14852459.8

申请日：2014-09-11

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： MATSUDA, Toshiya ,  HAMAOKA, Fukutaro ,  NAKA, Akira ,  SAITO, Kohei

IPC: H04B10/61 ,  H04J11/00 ,  H04J14/00 ,  H04J14/02 ,  H04J14/04 ,  H04J14/06

CPC classification number: H04J14/02 ,  H04B10/532 ,  H04B10/5561 ,  H04B10/6151 ,  H04B10/6161 ,  H04B10/6164 ,  H04B10/6165 ,  H04J14/06

Abstract: A receiver is configured to have two coherent receivers using two pieces of local oscillator of optical frequencies f11 and f12 close to optical frequency f1 of signal light, the two pieces of local oscillator being controlled to have a predetermined optical frequency spacing ΔF, and a digital signal processor demodulating transmission data signal sequences based on outputs from the coherent receivers. When the frequency difference Δf1 of one of the two pieces of local oscillator from a virtual reference frequency f1' close to the optical frequency f1 of the signal light is set, the digital signal processor obtains the frequency difference Δf2 of the other of the two pieces of local oscillator by calculating Δf1 - ΔF, inputs electric signals output from the two coherent receivers, and compensates the phase rotation caused in the electric signals by frequency differences Δf1 and Δf2.

Abstract translation: 接收机被配置为具有两个相干接收机，它们使用接近信号光的光频率f1的两个光频本地振荡器f11和f12，两个本地振荡器被控制为具有预定的光频间距“F”，而 数字信号处理器基于来自相干接收机的输出来解调传输数据信号序列。 当设置两个本地振荡器中的一个本地振荡器的距离与信号光的光频率f1接近的虚拟参考频率f1'的频率差“f1”时，数字信号处理器获得另一个的频率差“f2” 通过计算“f1 - ”F两个本地振荡器，输入从两个相干接收机输出的电信号，并通过频率差“f1”和“f2”补偿电信号中产生的相位旋转。

公开(公告)号：EP3021542A1

公开(公告)日：2016-05-18

申请号：EP15275235.8

申请日：2015-11-13

Applicant: ZTE Corporation

Inventor： Jia,, Zhensheng ,  Cai, Yi

IPC: H04L25/03

CPC classification number: H04B10/6165 ,  H04L1/0047 ,  H04L1/0054 ,  H04L7/048 ,  H04L25/03019 ,  H04L25/03267 ,  H04L25/03273 ,  H04L2025/03636

Abstract: A post-equalization technique for recovering data bits from a coherent modulation optical signal is implemented in the digital domain by iteratively performing a decision-directed least mean square channel equalization step, a digital post filter step and a maximum likelihood sequence estimation step so that the symbol decisions of the previous iteration are fed to the decision directed least mean square channel equalization step to successively improve the symbol decisions. In an experimental setup, the iterative technique demonstrated performance improvement mitigating the bandwidth limitation as compared to a corresponding non-iterative technique.

Abstract translation: 通过迭代地执行决策导向的最小均方信道均衡步骤，数字后置滤波器步骤和最大似然序列估计步骤，在数字域中实现用于从相干调制光信号中恢复数据比特的后均衡技术， 先前迭代的符号决定被馈送到决策导向的最小均方信道均衡步骤以连续地改进符号决定。 在实验设置中，与相应的非迭代技术相比，迭代技术显示了降低带宽限制的性能提升。