Zero-delay structure for sub-band echo cancellation
    1.
    发明授权
    Zero-delay structure for sub-band echo cancellation 有权
    用于子带回波消除的零延迟结构

    公开(公告)号:US06661895B1

    公开(公告)日:2003-12-09

    申请号:US09414413

    申请日:1999-10-07

    IPC分类号: H04M908

    CPC分类号: H04M9/082

    摘要: A zero-delay structure to be used in sub-band echo cancellation systems. In telecommunications, a delay is usually introduced in sub-band decomposition and/or sub-band reconstruction. This invention will help remove this. This structure not only removes the delay but does not sacrifice the performance of the echo canceller. It is to be used in combination with any sub-band-based echo canceller or wavelet echo canceller.

    摘要翻译: 用于子带回波消除系统的零延迟结构。 在电信中,通常在子带分解和/或子带重建中引入延迟。 本发明将有助于消除这一点。 该结构不仅消除延迟,而且不会牺牲回声消除器的性能。 它与任何基于子带的回波消除器或小波回波消除器组合使用。

    Sub-band echo canceller using optimum wavelet packets and cross-band
cancellation
    2.
    发明授权
    Sub-band echo canceller using optimum wavelet packets and cross-band cancellation 失效
    子带回波消除器使用最佳小波包和交叉带消除

    公开(公告)号:US5937009A

    公开(公告)日:1999-08-10

    申请号:US784849

    申请日:1997-01-15

    摘要: An echo canceller comprising a first wavelet decomposition block for decomposing a reference signal into a plurality of reference wavelet packets; a second wavelet decomposition block for decomposing an echo signal into a plurality of echo signal packets; an adaptive filter bank for receiving and filtering the reference wavelet packets and in response generating a plurality of filtered output packets replicating the echo signal packets; a plurality of subtracters for receiving and subtracting respective ones of the filtered output packets from the echo signal packets and in response generating and applying a plurality of error signals to the adaptive filter bank for modifying the transfer function of the adaptive filter bank; and a wavelet reconstruction block for receiving and reconstructing the error signals to form a residual signal from which the echo signal has been cancelled. Optimum wavelet filters for the best echo cancellation are provided, as are two wavelet echo cancellation structures.

    摘要翻译: 一种回波消除器,包括用于将参考信号分解成多个参考小波包的第一小波分解块; 第二小波分解块,用于将回波信号分解成多个回波信号分组; 自适应滤波器组,用于接收和滤波参考小波包,并且响应于产生复制回波信号分组的多个滤波输出分组; 多个减法器,用于从所述回波信号分组中接收和减去所述经滤波的输出分组中的相应的减法器,并且响应于产生并将多个误差信号施加到所述自适应滤波器组以修改所述自适应滤波器组的传递函数; 以及小波重建块,用于接收和重构误差信号以形成已经从其消除了回波信号的残余信号。 提供了用于最佳回波消除的最佳小波滤波器,两个小波回声消除结构也是如此。

    Nonlinear processor for acoustic echo canceller with background noise preservation and long echo tail suppression
    3.
    发明授权
    Nonlinear processor for acoustic echo canceller with background noise preservation and long echo tail suppression 有权
    用于声学回声消除器的非线性处理器,具有背景噪声保护和长回波尾部抑制

    公开(公告)号:US06282286B1

    公开(公告)日:2001-08-28

    申请号:US09143973

    申请日:1998-08-31

    IPC分类号: H04B320

    CPC分类号: H04B3/234

    摘要: A nonlinear processor (NLP) for selectively removing or reducing residual echo signals from an acoustic echo canceller associated with a telephony terminal is provided. Low level background noise and near end speech signals pass through the NLP structure substantially unaltered. Distortion, background noise above a preset threshold and echo signals including long duration echoes are replaced with a linear combination of previous noise data.

    摘要翻译: 提供了用于从与电话终端相关联的声学回声消除器中选择性地去除或减少残余回波信号的非线性处理器(NLP)。 低电平背景噪声和近端语音信号通过NLP结构基本上未改变。 高于预设阈值的失真,背景噪声以及包括长持续时间回波的回波信号被先前噪声数据的线性组合替代。

    Double-talk insensitive NLMS algorithm
    4.
    发明授权
    Double-talk insensitive NLMS algorithm 有权
    双语不敏感的NLMS算法

    公开(公告)号:US06608897B1

    公开(公告)日:2003-08-19

    申请号:US09175881

    申请日:1998-10-21

    IPC分类号: H04M176

    CPC分类号: H04M9/082

    摘要: A method of canceling echo signals in a telephone network operating in a double talk mode has been developed. A system for implementing the method is also presented. In the invention the conventional normalized least mean square (NLMS) algorithm for echo cancellers is modified such that echo path changes continue to be tracked even after a double talk condition has been detected. The modified algorithm, known herein as a double-talk normalized least mean square (DNLMS) algorithm adaptively adjusts the convergence rate based on the power difference between the echo signal or the residual signal and the far end signal.

    摘要翻译: 已经开发了以双通道模式操作的电话网络中消除回波信号的方法。 还提出了一种实现该方法的系统。 在本发明中,用于回波消除器的常规归一化最小均方(NLMS)算法被修改,使得即使在检测到双重通话条件之后,回波路径改变仍继续被跟踪。 经修改的算法,这里称为双方通话归一化最小均方(DNLMS)算法,基于回波信号或残差信号与远端信号之间的功率差自适应地调整收敛速度。

    Timing recovery with minimum jitter movement
    5.
    发明授权
    Timing recovery with minimum jitter movement 失效
    具有最小抖动运动的定时恢复

    公开(公告)号:US6138244A

    公开(公告)日:2000-10-24

    申请号:US163248

    申请日:1998-09-30

    CPC分类号: H04L7/0062 H04L7/0083

    摘要: A symbol synchronization and timing recovery method for stabilizing jitter in a data receiver is provided. A one tap LMS algorithm is used for a pre-cursor estimate. A dead zone is set around the desired timing location and the local clock in the receiver is updated only if the timing signal is outside of the dead zone.

    摘要翻译: 提供了一种用于稳定数据接收机中的抖动的符号同步和定时恢复方法。 一次性LMS算法用于前置估计。 在期望的定时位置周围设置死区,并且只有当定时信号在死区之外时才更新接收器中的本地时钟。

    Digital tone detector
    6.
    发明授权
    Digital tone detector 失效
    数字音检测器

    公开(公告)号:US4694482A

    公开(公告)日:1987-09-15

    申请号:US921526

    申请日:1986-10-22

    IPC分类号: H04Q1/457 H04M1/24

    CPC分类号: H04Q1/4575

    摘要: A digital progess tone detector, for connection to a telephone line and a PABX, comprising circuitry for generating one or more reference tones having user definable frequencies and performing single frequency discrete Fourier transforms on one or more signals received from the telephone line at the defined frequencies, and providing an output signal to the PABX in response thereto. The output signal provides an indication of whether or not a predetermined one or more progress tone frequencies have been detected in the received signals. Because the generated reference tone frequencies are user definable, the present invention can be easily adapted for use in various foreign countries having different progress tone frequency requirements. A preferred embodiment of the invention is implemented on a single microcomputer chip in conjunction with peripherals (such as codecs, crosspoint switches, etc.). The progress tone detector is simple, small and inexpensive, thus conforming to the miniaturization and cost efficiency requirements of modern day PABX circuits.

    摘要翻译: 一种用于连接到电话线路和PABX的数字渐进音检测器,包括用于产生具有用户可定义频率的一个或多个参考音调并且以定义的频率对从电话线接收的一个或多个信号执行单频离散付里叶变换的电路 并且响应于此向PABX提供输出信号。 输出信号提供在接收到的信号中是否已经检测到预定的一个或多个进行音频率的指示。 由于所生成的参考音频率是用户可定义的,因此本发明可以容易地适用于具有不同进度音频要求的各个国家。 结合外围设备(如编解码器,交叉点开关等),在单个微型计算机芯片上实现本发明的优选实施例。 进度音检测器简单,小巧便宜,符合现代PABX电路的小型化和成本效益要求。

    SCALEABLE VOIP TELEPHONE LINE CIRCUIT
    7.
    发明申请
    SCALEABLE VOIP TELEPHONE LINE CIRCUIT 有权
    可扩展的电话线路电路

    公开(公告)号:US20090154484A1

    公开(公告)日:2009-06-18

    申请号:US12332563

    申请日:2008-12-11

    IPC分类号: H04L12/66

    摘要: A telephone subscriber line device for providing an interface between a legacy telephone circuit based on circuit-switched technology and a packet network has a legacy interface for connection to telephone circuit; a packet interface for connection to a packet network, processing circuitry for converting between legacy telephone signals and packet signals, and a cascadable expansion bus permitting multiple said devices to be connected to a common port on a packet network. Such a device is highly scalable.

    摘要翻译: 用于在基于电路交换技术的传统电话电路与分组网络之间提供接口的电话用户线路设备具有用于连接到电话电路的传统接口; 用于连接到分组网络的分组接口,用于在传统电话信号和分组信号之间转换的处理电路,以及允许多个所述设备连接到分组网络上的公共端口的级联扩展总线。 这样的设备是高度可扩展的。

    Signal processing circuit
    8.
    发明授权
    Signal processing circuit 失效
    信号处理电路

    公开(公告)号:US5991784A

    公开(公告)日:1999-11-23

    申请号:US765205

    申请日:1997-04-24

    申请人: Gordon J. Reesor

    发明人: Gordon J. Reesor

    CPC分类号: H03M7/3046

    摘要: A circuit for applying a predetermined algorithm to an input signal, has an input for receiving the input signal, a signal processing device for processing the input signal in accordance with the predetermined algorithm, and a device for outputting the processed signal. The signal processing device incorporates distributed bit-serial logic circuits to implement the predetermined algorithm.

    摘要翻译: PCT No.PCT / CA95 / 00400 Sec。 371日期1997年04月24日 102(e)日期1997年4月24日PCT提交1995年7月6日PCT公布。 出版物WO96 / 01527 日期1996年1月18日用于对输入信号应用预定算法的电路具有用于接收输入信号的输入端,用于根据预定算法处理输入信号的信号处理装置,以及用于输出处理信号的装置 。 信号处理装置包括分布式位串行逻辑电路以实现预定算法。

    Digital loudspeaking telephone
    9.
    发明授权
    Digital loudspeaking telephone 失效
    数字式扬声电话

    公开(公告)号:US4796287A

    公开(公告)日:1989-01-03

    申请号:US781020

    申请日:1985-09-27

    摘要: A digital loudspeaking telephone for connection to a telephone line, including a microphone, speaker, codec and digital signal processor. Incoming and outgoing signals are received by the digital signal processor from remote and local subscribers via the telephone line and microphone respectively. The processor generates and compares incoming and outgoing envelope and noise floor signal levels derived from the received incoming and outgoing signals and in response suppresses a particular compared, and one of the incoming or outgoing signals. Automatic gain control of outgoing signals is implemented in order to allow smooth switching of the outgoing signals and to suppress background noise from being transmitted by the microphone. Room echo and reverberation are also detected, and the processor eliminates spurious channel switching due to the detected echo signals.

    摘要翻译: 一种用于连接到电话线的数字扬声电话,包括麦克风,扬声器,编解码器和数字信号处理器。 数字信号处理器分别通过电话线和麦克风从远端和本地用户接收传入和传出信号。 处理器产生并比较从接收到的输入和输出信号导出的进入和输出的包络和本底噪声信号电平,并且在响应中抑制特定的比较和输入或输出信号之一。 实现输出信号的自动增益控制,以便允许输出信号的平滑切换并且抑制背景噪声被麦克风发送。 还检测到房间回声和混响,并且处理器由于检测到的回波信号而消除杂散信道切换。

    Digital tone detector
    10.
    发明授权
    Digital tone detector 失效
    数字音检测器

    公开(公告)号:US4669114A

    公开(公告)日:1987-05-26

    申请号:US705679

    申请日:1985-02-26

    IPC分类号: H04Q1/457 H04M3/00

    CPC分类号: H04Q1/4575

    摘要: A digital progress tone detector, for connection to a telephone line and a PABX, comprising circuitry for generating one or more reference tones having user definable frequencies and performing single frequency discrete Fourier transforms on one or more signals received from the telephone line at the defined frequencies, and providing an output signal to the PABX in response thereto. The output signal provides an indication of whether or not a predetermined one or more progress tone frequencies have been detected in the received signals. Because the generated reference tone frequencies are user definable, the present invention can be easily adapted for use in various foreign countries having different progress tone frequency requirements. A preferred embodiment of the invention is implemented on a single microcomputer chip in conjunction with peripherals (such as codecs, crosspoint switches, etc.). The progress tone detector is simple, small and inexpensive, thus conforming to the miniaturization and cost efficiency requirements of modern day PABX circuits.

    摘要翻译: 一种用于连接到电话线和PABX的数字进步音检测器,包括用于产生具有用户可定义频率的一个或多个参考音调并且以定义的频率对从电话线接收的一个或多个信号执行单频离散付里叶变换的电路 并且响应于此向PABX提供输出信号。 输出信号提供在接收到的信号中是否已经检测到预定的一个或多个进行音频率的指示。 由于所生成的参考音频率是用户可定义的,因此本发明可以容易地适用于具有不同进度音频要求的各个国家。 结合外围设备(如编解码器,交叉点开关等),在单个微型计算机芯片上实现本发明的优选实施例。 进度音检测器简单,小巧便宜,符合现代PABX电路的小型化和成本效益要求。