公开(公告)号：US06278775B1

公开(公告)日：2001-08-21

申请号：US09266521

申请日：1999-03-11

申请人： Gilbert C. Sih ,  Johnny K. John

发明人： Gilbert C. Sih ,  Johnny K. John

IPC分类号： H04M1100

CPC分类号： H04N1/32708 ,  H04M1/725 ,  H04N1/32704 ,  H04N1/32715 ,  H04N1/32721

摘要： A novel and improved method and apparatus for providing an interface to a digital wireless telephone system compatible with standard analog wire line telephones and analog wire line fax machines is disclosed. During a telephone call, a fax detector monitors the incoming data for fax signals. If a fax is detected, the data processor switches from processing the data as if it were voice to processing it as fax In addition, the remote station is sent a signal notifying it to process the data as fax rather than voice. The fax detector operates by detecting the preamble of a V.21 message, present at the beginning of every fax call. Energy is measured in both frequencies of the BFSK signals. A decision is made by analyzing these energies and locating a specific pattern which repeats itself a sufficient number of times.

摘要翻译： 公开了一种用于向与标准模拟有线电话和模拟有线线路传真机兼容的数字无线电话系统提供接口的新型改进的方法和装置。 在电话呼叫期间，传真机检测器监视传入信号的传入数据。 如果检测到传真，则数据处理器将处理数据转换为处理数据，就像将其作为传真处理一样。此外，远程站发送一个信号，通知它将数据作为传真处理，而不是语音。 传真检测器通过检测在每个传真呼叫开始时出现的V.21消息的前导码来进行操作。 在BFSK信号的两个频率上测量能量。 通过分析这些能量并找到重复自身足够次数的特定模式来做出决定。

公开(公告)号：US5903862A

公开(公告)日：1999-05-11

申请号：US575287

申请日：1996-01-11

申请人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William R. Gardner ,  Paul E. Jacobs ,  Andrew P. DeJaco ,  Gilbert C. Sih

发明人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William R. Gardner ,  Paul E. Jacobs ,  Andrew P. DeJaco ,  Gilbert C. Sih

IPC分类号： G10L11/02 ,  G10L19/00 ,  G10L19/14 ,  H04B7/26 ,  H04B14/04 ,  H04Q11/04 ,  H04W88/18 ,  G10L9/18 ,  H04Q7/24

CPC分类号： H04W88/181 ,  G10L19/16

摘要： When one vocoding system is coupled to another vocoding system, a tandem arrangement results. The tandem configuration results in voice quality degradation as speech is encoded and decoded, then encoded and decoded again. One reason for the degradation is that postfiltering performed at the output of the speech decoding process introduces distortions in the spectral content of the reconstructed speech as compared to the original speech. The present invention prevents the degradation due to the use of postfilters by modifying the postfiltering within the vocoders where a tandem configuration exists. A detection code is embedded within the data signal to indicate the existence of a tandem configuration. If the detection code is received at a vocoder, modified vocoding is established within the vocoders to prevent the degradation due to the postfiltering.

摘要翻译： 当一个声码系统耦合到另一个声码系统时，会产生串联排列。 串音配置导致语音质量下降，因为语音被编码和解码，然后被再次编码和解码。 降级的一个原因是在语音解码过程的输出处执行的后置滤波与原始语音相比引入了重构语音的频谱内容中的失真。 本发明通过修改存在串列配置的声码器中的后置滤波来防止由于使用后置滤波器导致的劣化。 检测码嵌入在数据信号中以指示串联配置的存在。 如果在声码器处接收到检测码，则在声码器内建立修改后的声码，以防止由于后置滤波引起的劣化。

公开(公告)号：US5687229A

公开(公告)日：1997-11-11

申请号：US607403

申请日：1996-02-23

申请人： Gilbert C. Sih

发明人： Gilbert C. Sih

IPC分类号： H04M1/60 ,  G10L19/012 ,  H04B3/23 ,  H04M9/08 ,  H04B3/20

CPC分类号： H04B3/234 ,  G10L19/012 ,  H04B3/23 ,  H04M9/082

摘要： A method for controlling echo canceling in an echo cancellation system using a state machine controller. A far-end speech signal transmitted through a communications channel may be passed through an echo channel to produce an echo signal. The echo signal is summed with a near-end speech signal and transmitted back to the far-end. An echo canceller rejects the echo signal by forming an estimate of the echo signal and subtracting the estimate from the sum of the near-end speech signal and the echo signal. The echo canceller includes a state machine which is configured into a predetermined state of a plurality of states depending on the presence near-end speech signal, far-end speech signal, or both near-end and far-end speech signals. Based on the predetermined state of the state machine, the controller in the state machine controls the update of coefficients of a plurality of adaptive filters. The adaptive filters filter the far-end signal to form the estimate of the echo signal, which is canceled from an output signal provided to an output speech channel at the far-end.

摘要翻译： 一种使用状态机控制器来控制回波消除系统中的回波消除的方法。 可以通过通信信道发送的远端语音信号通过回波信道以产生回波信号。 回波信号与近端语音信号相加并传送回远端。 回声消除器通过形成回波信号的估计并从近端语音信号和回波信号的和中减去估计来拒绝回波信号。 回波消除器包括状态机，其根据存在的近端语音信号，远端语音信号或近端和远端语音信号两者被配置为多个状态的预定状态。 基于状态机的预定状态，状态机中的控制器控制多个自适应滤波器的系数的更新。 自适应滤波器对远端信号进行滤波以形成回波信号的估计，其从提供给远端的输出语音信道的输出信号中消除。

公开(公告)号：US5559881A

公开(公告)日：1996-09-24

申请号：US202520

申请日：1994-02-28

申请人： Gilbert C. Sih

发明人： Gilbert C. Sih

IPC分类号： H04M1/60 ,  G10L19/012 ,  H04B3/23 ,  H04M9/08 ,  H04B3/20

CPC分类号： H04B3/234 ,  G10L19/012 ,  H04B3/23 ,  H04M9/082

摘要： An echo canceller and method for cancelling in a return channel signal an echoed receive channel signal where the echoed receive channel signal is combined by an echo channel with an input return channel signal. The echo canceller has a first filter which generates first filter coefficients, generates a first echo estimate signal with the first filter coefficients, and updates the first filter coefficients in response to a first filter control signal. A first summer subtracts the first echo estimate signal from a combined return channel and echo receive channel signal to generate a first echo residual signal. A second filter generates second filter coeffidents, generates a second echo estimate signal with the second filter coefficients, and updates the second filter coefficients in response to a second filter control signal. A second summer subtracts the second echo estimate signal from the combined signal to generate a second echo residual signal, and provides upon the return channel the second echo residual signal. A control unit determines from the receive channel signal, the combined signal, and the first and second echo residual signals, one of a plurality of control states wherein a first control state is indicative of a receive channel signal above a first predetermined energy level, wherein when the control unit is in the first control state it generates the first control signal and generates the second control signal when at least one of a first energy ratio of the first echo residual signal and the combined signal and a second energy ratio of the second echo residual signal and the combined signal exceed a predetermined level.

摘要翻译： 回波消除器和用于在返回信道中消除回波的接收信道信号的方法，其中回波的接收信道信号由回波信道与输入返回信道信号组合。 回波消除器具有产生第一滤波器系数的第一滤波器，产生具有第一滤波器系数的第一回波估计信号，并响应于第一滤波器控制信号来更新第一滤波器系数。 第一个夏季从组合返回信道和回波接收信道信号中减去第一回波估计信号，以产生第一回波残差信号。 第二滤波器产生第二滤波器系数，产生具有第二滤波器系数的第二回波估计信号，并且响应于第二滤波器控制信号来更新第二滤波器系数。 第二个夏天从组合信号中减去第二回波估计信号，以产生第二回波残差信号，并在返回信道上提供第二回波残留信号。 控制单元从接收信道信号，组合信号以及第一和第二回波残余信号中确定多个控制状态中的一个，其中第一控制状态指示高于第一预定能级的接收信道信号，其中 当所述控制单元处于所述第一控制状态时，产生所述第一控制信号，并且当所述第一回波残留信号和所述组合信号的第一能量比和所述第二回波的第二能量比中的至少一个产生所述第二控制信号时， 剩余信号和组合信号超过预定水平。

公开(公告)号：US07873815B2

公开(公告)日：2011-01-18

申请号：US10794300

申请日：2004-03-04

申请人： Gilbert C. Sih ,  De D. Hsu ,  Way-Shing Lee ,  Xufeng Chen

发明人： Gilbert C. Sih ,  De D. Hsu ,  Way-Shing Lee ,  Xufeng Chen

IPC分类号： G06F7/38

CPC分类号： G06F9/30014 ,  G06F9/30032 ,  G06F9/3875 ,  G06F9/3885 ,  G06F9/3893

摘要： DSP architectures having improved performance are described. In an exemplary architecture, a DSP includes two MAC units and two ALUs, where one of the ALUs replaces an adder for one of the two MAC units. This DSP may be configured to operate in a dual-MAC/single-ALU configuration, a single-MAC/dual-ALU configuration, or a dual-MAC/dual-ALU configuration. This flexibility allows the DSP to handle various types of signal processing operations and improves utilization of the available hardware. The DSP architectures further includes pipeline registers that break up critical paths and allow operations at a higher clock speed for greater throughput.

摘要翻译： 描述了具有改进性能的DSP架构。 在示例性架构中，DSP包括两个MAC单元和两个ALU，其中一个ALU替换两个MAC单元之一的加法器。 该DSP可以被配置为以双MAC /单ALU配置，单MAC /双ALU配置或双MAC /双ALU配置来操作。 这种灵活性允许DSP处理各种类型的信号处理操作，并提高可用硬件的利用率。 DSP架构还包括流水线寄存器，其分解关键路径，并允许以更高的时钟速度进行操作以获得更高的吞吐量。

公开(公告)号：US06606700B1

公开(公告)日：2003-08-12

申请号：US09513979

申请日：2000-02-26

申请人： Gilbert C. Sih ,  Hemant Kumar ,  Way-Shing Lee

发明人： Gilbert C. Sih ,  Hemant Kumar ,  Way-Shing Lee

IPC分类号： G06F1582

CPC分类号： G06F9/3877 ,  G06F7/4812 ,  G06F7/5443 ,  G06F9/3001 ,  G06F9/3893 ,  G06F15/7817

摘要： The invention is a digital signal processor architecture that is designed to speed up frequently-used signal processing computations, such as FIR filters, correlations, FFTs, and DFTs. The architecture uses a coupled dual-MAC architecture (MAC1), (MAC2) and attaches a dual-MAC coprocessor (MAC3), (MAC4) onto it in a unique way to achieve a significant increase in processing capability.

摘要翻译： 本发明是一种数字信号处理器架构，其被设计为加速频繁使用的信号处理计算，例如FIR滤波器，相关性，FFT和DFT。 该架构使用耦合的双MAC架构（MAC1）（MAC2），并以独特的方式将双MAC协处理器（MAC3）（MAC4）附加到其上，以实现处理能力的显着增加。

公开(公告)号：US06233549B1

公开(公告)日：2001-05-15

申请号：US09199072

申请日：1998-11-23

申请人： Anthony P. Mauro ,  Gilbert C. Sih

发明人： Anthony P. Mauro ,  Gilbert C. Sih

IPC分类号： G10L1906

CPC分类号： G10L21/02 ,  G10L21/0232

摘要： A system for enhancing low frequency spectral content of a digitized signal which identifies a fundamental frequency component in the signal and selectively boosts signals within a predetermined range thereof. In the illustrative embodiment, the digitized signal is a frequency domain transformed speech signal. The invention amplifies the low frequency components of the speech signal. The speaker unique fundamental frequency of the speech is computed using pitch delay information and is thus dynamic from frame to frame and also speaker to speaker. This fundamental frequency defines the center point of a gain window which is applied to select frequency components. Only such fundamental frequency components which exhibit a large enough signal to noise ratio have the amplification function applied. Thus, this function can be applied directly following a noise suppression system which has knowledge of the signal quality in each frequency bin. The gain window is ramped up and hanged over to smooth the amplification function between successive frames.

摘要翻译： 一种用于增强数字化信号的低频谱含量的系统，其识别信号中的基频分量并且选择性地提高其预定范围内的信号。 在说明性实施例中，数字化信号是频域变换的语音信号。 本发明放大语音信号的低频分量。 使用音调延迟信息来计算扬声器独特的基本频率，并且因此是帧间动态的，而扬声器也是扬声器。 该基本频率定义了应用于选择频率分量的增益窗口的中心点。 仅具有足够大的信噪比的基频分量具有应用的放大功能。 因此，该功能可以直接应用于具有每个频率仓中的信号质量知识的噪声抑制系统。 增益窗口上升并挂起，以平滑连续帧之间的放大功能。

公开(公告)号：US5646991A

公开(公告)日：1997-07-08

申请号：US607402

申请日：1996-02-23

申请人： Gilbert C. Sih

发明人： Gilbert C. Sih

IPC分类号： H04M1/60 ,  G10L19/012 ,  H04B3/23 ,  H04M9/08 ,  H04B3/20

CPC分类号： H04B3/234 ,  G10L19/012 ,  H04B3/23 ,  H04M9/082

摘要： A noise replacement system and method for providing a synthesized noise replacement signal to an output speech channel in an echo cancellation system. A far-end speech signal transmitted through a communications channel may be passed through an echo channel to produce an echo signal. The echo signal is summed with near-end speech and transmitted back to the far-end in the output speech channel. An echo canceller rejects the echo signal by forming an estimate of the echo signal and subtracting the estimate from the sum of the near-end speech and the echo signal to produce an echo residual signal. When only the far-end speaker is talking, the echo is completely rejected by replacing the echo residual signal with a synthesized noise signal. The noise is synthesized to match the power and spectral characteristics of the actual background noise at the near-end to prevent the far-end speaker from detecting any change in signal characteristics.

摘要翻译： 一种用于向回声消除系统中的输出语音信道提供合成噪声置换信号的噪声替换系统和方法。 可以通过通信信道发送的远端语音信号通过回波信道以产生回波信号。 回波信号与近端语音求和并传输回输出语音信道中的远端。 回波消除器通过形成回波信号的估计并从近端语音和回波信号的和减去估计值来拒绝回波信号，以产生回波残留信号。 当只有远端扬声器正在说话时，通过用合成噪声信号代替回波残差信号，完全拒绝回波。 合成噪声以匹配近端实际背景噪声的功率和频谱特性，以防止远端扬声器检测信号特性的任何变化。

公开(公告)号：US5644596A

公开(公告)日：1997-07-01

申请号：US528391

申请日：1995-09-13

申请人： Gilbert C. Sih

发明人： Gilbert C. Sih

IPC分类号： H03H21/00 ,  H03H7/30

CPC分类号： H03H21/0012 ,  H03H2021/0041 ,  H03H2021/0089

摘要： A method and apparatus for performing subband adaptive filtering is proposed. A signal is prefiltered by a set of complementary filters to provide corresponding subbands of the input signal. The subbands of the signal are then provided to adaptive filters that filter the subbands separately. The individually filtered subbands are then summed. In an exemplary implementation an echo canceller is presented which employs the subband filtering method and apparatus.

摘要翻译： 提出了一种用于执行子带自适应滤波的方法和装置。 信号由一组互补滤波器预过滤，以提供输入信号的相应子带。 然后将信号的子带提供给分别过滤子带的自适应滤波器。 然后将单独滤波的子带相加。 在示例性实施例中，呈现采用子带滤波方法和装置的回波消除器。

公开(公告)号：US5307405A

公开(公告)日：1994-04-26

申请号：US951074

申请日：1992-09-25

申请人： Gilbert C. Sih

发明人： Gilbert C. Sih

IPC分类号： H04M1/60 ,  G10L19/012 ,  H04B3/23 ,  H04M9/08 ,  H04M1/00

CPC分类号： H04B3/234 ,  G10L19/012 ,  H04B3/23 ,  H04M9/082

摘要： An echo canceller and method for cancelling in a return channel signal an echoed receive channel signal where the echoed receive channel signal is combined by an echo channel with an input return channel signal. The echo canceller has a first filter which generates first filter coefficients, generates a first echo estimate signal with the first filter coefficients, and updates the first filter coefficients in response to a first filter control signal. A first summer subtracts the first echo estimate signal from a combined return channel and echo receive channel signal to generate a first echo residual signal. A second filter generates second filter coefficients, generates a second echo estimate signal with the second filter coefficients, and updates the second filter coefficients in response to a second filter control signal. A second summer subtracts the second echo estimate signal from the combined signal to generate a second echo residual signal, and provides upon the return channel the second echo residual signal. A control unit determines from the receive channel signal, the combined signal, and the first and second echo residual signals, one of a plurality of control states wherein a first control state is indicative of a receive channel signal above a first predetermined energy level, wherein when the control unit is in the first control state it generates the first control signal and generates the second control signal when at least one of a first energy ratio of the first echo residual signal and the combined signal and a second energy ratio of the second echo residual signal and the combined signal exceed a predetermined level.

摘要翻译： 回波消除器和用于在返回信道中消除回波的接收信道信号的方法，其中回波的接收信道信号由回波信道与输入返回信道信号组合。 回波消除器具有产生第一滤波器系数的第一滤波器，产生具有第一滤波器系数的第一回波估计信号，并响应于第一滤波器控制信号来更新第一滤波器系数。 第一个夏季从组合返回信道和回波接收信道信号中减去第一回波估计信号，以产生第一回波残差信号。 第二滤波器产生第二滤波器系数，产生具有第二滤波器系数的第二回波估计信号，并且响应于第二滤波器控制信号来更新第二滤波器系数。 第二个夏天从组合信号中减去第二回波估计信号，以产生第二回波残差信号，并在返回信道上提供第二回波残留信号。 控制单元从接收信道信号，组合信号以及第一和第二回波残余信号中确定多个控制状态中的一个，其中第一控制状态指示高于第一预定能级的接收信道信号，其中 当所述控制单元处于所述第一控制状态时，产生所述第一控制信号，并且当所述第一回波残留信号和所述组合信号的第一能量比和所述第二回波的第二能量比中的至少一个产生所述第二控制信号时， 剩余信号和组合信号超过预定水平。