公开(公告)号：US07974181B2

公开(公告)日：2011-07-05

申请号：US12138731

申请日：2008-06-13

Applicant: Amitkumar Mahadevan ,  Patrick Duvaut ,  Harish Jethanandani ,  Rahul Garg

Inventor： Amitkumar Mahadevan ,  Patrick Duvaut ,  Harish Jethanandani ,  Rahul Garg

IPC: H04J11/00

CPC classification number: H04L27/2618

Abstract: Systems and methods for reducing the peak-to-average power ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal in the oversampled regime, using tones reserved for PAR reduction. A set of vectors corresponding to PAR tones is generated by processing out-of-phase symbols for each PAR tone to form a span matrix. The span matrix is used to find a best fit of a desired target signal to a time-domain compensation signal comprising only PAR tones.

Abstract translation: 用于降低发射机的峰均功率比（PAR）的系统和方法可以减少各种模拟组件所需的动态范围。 可以通过在过采样方案中应用时域补偿信号，使用保留给PAR减少的音调来减少PAR。 通过处理每个PAR色调的异相符号来生成对应于PAR色调的一组矢量以形成跨度矩阵。 跨度矩阵用于找到期望目标信号对仅包括PAR色调的时域补偿信号的最佳拟合。

公开(公告)号：US07957477B2

公开(公告)日：2011-06-07

申请号：US11845040

申请日：2007-08-25

Applicant: Patrick Duvaut ,  Amitkumar Mahadevan ,  Massimo Sorbara ,  Ehud Langberg

Inventor： Patrick Duvaut ,  Amitkumar Mahadevan ,  Massimo Sorbara ,  Ehud Langberg

IPC: H04L27/28

CPC classification number: H04B3/32 ,  H04L1/0042

Abstract: Systems and methods for off-diagonal MIMO precoders are described. At least one embodiment includes a method for precoding data for transmission in a discrete multi-tone (DMT) xDSL system to cancel self-induced far end crosstalk (self-FEXT) comprising: learning characteristics associated with a plurality of N users within the xDSL system to determine an initial off-diagonal multiple input multiple output (MIMO) precoder (ODMP) for a given tone frequency; and converging towards an optimum ODMP from the initial ODMP in order to cancel downstream self-FEXT for the plurality of N users, wherein the ODMP is represented as a zero diagonal matrix with only off-diagonal terms, and wherein the converging towards the optimum ODMP comprises: maximizing the channel capacity for the plurality of N users for the given tone frequency; and minimizing an increase in transmit power of the xDSL system relative to an original transmit power where a precoder is not active.

Abstract translation: 描述了非对角MIMO预编码器的系统和方法。 至少一个实施例包括用于预编码用于在离散多音（DMT）xDSL系统中传输的数据以消除自感应远端串扰（self-FEXT）的方法，包括：与xDSL内的多个N个用户相关联的学习特征 系统确定用于给定音频的初始非对角多输入多输出（MIMO）预编码器（ODMP）; 并从最初的ODMP收敛到最佳的ODMP，以消除多个N个用户的下游自身FEXT，其中ODMP被表示为只有非对角项的零对角矩阵，并且其中朝向最佳ODMP 包括：使给定音调频率的多个N个用户的信道容量最大化; 并且最小化xDSL系统相对于预编码器不活动的原始发射功率的发射功率的增加。

公开(公告)号：US20100278328A1

公开(公告)日：2010-11-04

申请号：US12431878

申请日：2009-04-29

Applicant: Amitkumar Mahadevan ,  Patrick Duvaut ,  Laurent Francis Alloin

Inventor： Amitkumar Mahadevan ,  Patrick Duvaut ,  Laurent Francis Alloin

IPC: H04B3/32

CPC classification number: H04B3/32

Abstract: Systems and methods are described for selecting tones for far-end crosstalk (FEXT) mitigation. In particular, systems and methods are described for performing far-end crosstalk (FEXT) mitigation within a digital subscriber line (xDSL) system. One embodiment is a method that comprises determining a first set of function values relating to a per-tone signal-to-noise ratio (SNR) for a user among a plurality of users for a number of tones, wherein the number of tones is less than or equal to a total number of tones available for transmission. The method further comprises estimating coefficients for performing FEXT mitigation for the number of tones, performing FEXT mitigation on the number of tones based on the estimated coefficients, and performing FEXT mitigation on a selected group of tones from among the number of tones, wherein the selected group of tones is less than or equal to the number tones.

Abstract translation: 描述了用于选择用于远端串扰（FEXT）减轻的音调的系统和方法。 特别地，描述了用于在数字用户线（xDSL）系统内执行远端串扰（FEXT）减轻的系统和方法。 一个实施例是一种方法，其包括确定与多个用户之间的用户对于多个音调的用户的每音调信噪比（SNR）有关的第一功能值集合，其中，音调数量较少 超过或等于可用于传输的总音数。 该方法还包括估计用于对音调数执行FEXT减轻的系数，基于估计的系数对音调数执行FEXT减轻，以及从所选择的音数中对所选择的音调组执行FEXT减轻，其中所选择的 一组音调小于或等于数字音。

公开(公告)号：US20100061437A1

公开(公告)日：2010-03-11

申请号：US12348565

申请日：2009-01-05

Applicant: Hemant Samdani ,  Kunal Raheja ,  Rahul Garg ,  Amitkumar Mahadevan ,  Patrick Duvaut

Inventor： Hemant Samdani ,  Kunal Raheja ,  Rahul Garg ,  Amitkumar Mahadevan ,  Patrick Duvaut

IPC: H04B17/00

CPC classification number: H04B3/46

Abstract: Impulse noise from nearby or intense electrical sources can disrupt communications over digital subscriber lines (DSL). The characterization of the nature, timing and length of impulse noise sources present on a DSL loop is a critical first step in mitigating the effect of impulse noise on DSL communications. DSL standards provide histograms for impulse length and inter-arrival time of impulses. These histograms can be used to derive the nature, maximum frequency and other statistics related to impulse noise on a DSL line.

Abstract translation: 来自附近或强电场的脉冲噪声可能会扰乱通过数字用户线路（DSL）的通信。 存在于DSL环路上的脉冲噪声源的性质，时间和长度的表征是减轻脉冲噪声对DSL通信的影响的关键的第一步。 DSL标准提供脉冲长度和脉冲到达间隔时间的直方图。 这些直方图可用于导出与DSL线路上的脉冲噪声有关的性质，最大频率和其他统计。

公开(公告)号：US07660260B2

公开(公告)日：2010-02-09

申请号：US11712125

申请日：2007-02-28

Applicant: Patrick Duvaut ,  Amitkumar Mahadevan ,  Massimo Sorbara

Inventor： Patrick Duvaut ,  Amitkumar Mahadevan ,  Massimo Sorbara

IPC: H04J1/16 ,  H04B1/38

CPC classification number: H04M11/062

Abstract: There is provided a method of shaping PSD (Power Spectrum Density) of an FTTN (Fiber-To-The-Node) downstream signal from a disturber source to achieve spectral compatibility at an FTTN downstream victim with a downstream PSD from a reference source. The method includes receiving the downstream PSD from the reference source. The method further includes receiving an unshaped downstream PSD from the disturber source. The method further includes shaping the PSD of the FTTN downstream signal to have a substantially equivalent FEXT (Far-End Cross-Talk) into the FTTN downstream victim as the downstream PSD from the reference source.

Abstract translation: 提供了一种从干扰源获得FTTN（光纤到节点）下行信号的PSD（功率谱密度）的方法，以在具有来自参考源的下游PSD的FTTN下游受害者处获得频谱兼容性。 该方法包括从参考源接收下游PSD。 该方法还包括从干扰源接收未形成的下游PSD。 该方法还包括对FTTN下行信号的PSD进行整形，以使作为来自参考源的下游PSD的FTTN下游受害者具有基本相等的FEXT（远端交叉对话）。

公开(公告)号：US20080279269A1

公开(公告)日：2008-11-13

申请号：US12044531

申请日：2008-03-07

Applicant: Patrick Duvaut ,  Amitkumar Mahadevan ,  Vaibhav Dinesh

Inventor： Patrick Duvaut ,  Amitkumar Mahadevan ,  Vaibhav Dinesh

IPC: H04B3/46

CPC classification number: H04M3/302 ,  H04M3/085

Abstract: Systems and methods for performing loop termination are described. One embodiment is a method that comprises receiving a per-port calibrated echo signal of a loop under test, receiving a region designation and a loop length for the loop under test, and determining whether the loop is terminated by a short or open termination based on phase of the per-port calibrated echo signal.

Abstract translation: 描述用于执行环路终止的系统和方法。 一个实施例是一种方法，其包括接收被测环路的每端口校准的回波信号，接收被测环路的区域指定和环路长度，以及基于基于 每端口校准回波信号的相位。

公开(公告)号：US08885736B2

公开(公告)日：2014-11-11

申请号：US12138657

申请日：2008-06-13

Applicant: Rahul Garg ,  Patrick Duvaut ,  Amitkumar Mahadevan ,  Harish Jethanandani

Inventor： Rahul Garg ,  Patrick Duvaut ,  Amitkumar Mahadevan ,  Harish Jethanandani

IPC: H04K1/10 ,  H04L27/28 ,  H04M11/06

CPC classification number: H04M11/062

Abstract: Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the typical startup procedures in a digital subscriber line (xDSL) system. The use of the reserved tones to reduce the PAR can be implemented using a low complexity algorithm or using an adaptive technique.

Abstract translation: 用于降低发射机峰值平均比（PAR）的系统和方法可以减少各种模拟组件所需的动态范围。 可以通过应用时域补偿信号来减小PAR，该时域补偿信号在时域补偿信号使用为了减少PAR的目的而被保留的音调的同时减小时域信号中的峰值的幅度。 可以通过改变数字用户线（xDSL）系统中的典型启动过程来实现用于PAR的这些保留音调的预留。 可以使用低复杂度算法或使用自适应技术来实现使用保留的音调来减少PAR。

公开(公告)号：US08576690B2

公开(公告)日：2013-11-05

申请号：US13051906

申请日：2011-03-18

Applicant: Laurent Pierrugues ,  Laurent Francis Alloin ,  Amitkumar Mahadevan

Inventor： Laurent Pierrugues ,  Laurent Francis Alloin ,  Amitkumar Mahadevan

IPC: H04J1/12

CPC classification number: H04B1/1027 ,  H04B3/32 ,  H04L25/03012 ,  H04L25/03159

Abstract: In accordance with one embodiment, a method is implemented in a vectored system for improving a signal-to-noise ratio (SNR) of a far end transmitted signal on a victim line in the system. The method comprises mitigating, by the vectored system, self-induced far-end crosstalk (self-FEXT) on the victim line based on self-FEXT mitigation coefficients and receiving, by a second sensor, information relating to at least one of: self-FEXT of the vectored system, external noise, and the far end transmitted signal. The method further comprises learning, at the second sensor, coefficients relating to self-FEXT coupling into the second sensor and removing self-FEXT from the second sensor based on the learned coefficients. Upon removal of self-FEXT from the second sensor, a linear combiner configured to combine information relating to the victim line and the second line is learned. The method further comprises applying the learned linear combiner and readjusting the self-FEXT mitigation coefficients to remove any residual self-FEXT on the victim line after application of the learned linear combiner.

Abstract translation: 根据一个实施例，在矢量系统中实现一种方法，用于改善系统中受害线路上的远端发射信号的信噪比（SNR）。 该方法包括通过矢量系统减轻基于自FEXT减轻系数的受害线路上的自身诱发的远端串扰（self-FEXT），并且由第二传感器接收与以下至少一个相关的信息：自身 -OFXT的矢量系统，外部噪声和远端传输信号。 该方法还包括在第二传感器处学习与第二传感器的自FEXT耦合有关的系数，并且基于所学习的系数从第二传感器中去除自FEXT。 在从第二传感器移除自身FEXT时，学习用于组合与受害线和第二线有关的信息的线性组合器。 该方法还包括应用所学习的线性组合器并且重新调整自FEXT缓解系数以在施加学习的线性组合器之后去除受害线上的任何残余自FEXT。

公开(公告)号：US08509389B2

公开(公告)日：2013-08-13

申请号：US12044443

申请日：2008-03-07

Applicant: Patrick Duvaut ,  Amitkumar Mahadevan ,  Vaibhav Dinesh

Inventor： Patrick Duvaut ,  Amitkumar Mahadevan ,  Vaibhav Dinesh

IPC: H04M3/22

CPC classification number: H04M3/302 ,  H04M3/085

Abstract: Systems and methods for performing loop length estimation are described. One embodiment includes a method which comprises receiving an echo signal for a loop under test where the echo signal is a per-port calibrated echo response obtained using frequency domain reflectometry single-ended line testing (FDR-SELT). The method further comprises analyzing characteristics of the echo signal to perform a loop length estimation based on data relating to ripple frequency as a function of loop length.

Abstract translation: 描述了用于执行环路长度估计的系统和方法。 一个实施例包括一种方法，其包括接收用于测试环路的回波信号，其中回波信号是使用频域反射测量单端线测试（FDR-SELT）获得的每端口校准的回波响应。 该方法还包括分析回波信号的特性，以便根据与纹波频率相关的数据作为循环长度的函数来执行环路长度估计。

公开(公告)号：US08396688B2

公开(公告)日：2013-03-12

申请号：US12348565

申请日：2009-01-05

Applicant: Hemant Kumar Samdani ,  Kunal Raheja ,  Rahul Garg ,  Amitkumar Mahadevan ,  Patrick Duvaut

Inventor： Hemant Kumar Samdani ,  Kunal Raheja ,  Rahul Garg ,  Amitkumar Mahadevan ,  Patrick Duvaut

IPC: G06F17/18 ,  H04B15/00 ,  H04Q1/20 ,  G01R29/26

CPC classification number: H04B3/46

Abstract: Impulse noise from nearby or intense electrical sources can disrupt communications over digital subscriber lines (DSL). The characterization of the nature, timing and length of impulse noise sources present on a DSL loop is a critical first step in mitigating the effect of impulse noise on DSL communications. DSL standards provide histograms for impulse length and inter-arrival time of impulses. These histograms can be used to derive the nature, maximum frequency and other statistics related to impulse noise on a DSL line.

Abstract translation: 来自附近或强电场的脉冲噪声可能会扰乱通过数字用户线路（DSL）的通信。 存在于DSL环路上的脉冲噪声源的性质，时间和长度的表征是减轻脉冲噪声对DSL通信的影响的关键的第一步。 DSL标准提供脉冲长度和脉冲到达间隔时间的直方图。 这些直方图可用于导出与DSL线路上的脉冲噪声有关的性质，最大频率和其他统计。