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    Communication system
    91.
    发明申请
    Communication system 失效
    通讯系统

    公开(公告)号：US20020097336A1

    公开(公告)日：2002-07-25

    申请号：US09741429

    申请日：2000-12-21

    发明人： Mitsuaki Oshima

    IPC分类号： H04N007/12 ,  H04N005/38

    CPC分类号： H04L1/0047 ,  H03M13/256 ,  H03M13/35 ,  H04L1/0041 ,  H04L1/0042 ,  H04L1/0054 ,  H04L1/0057 ,  H04L1/006 ,  H04L1/0065 ,  H04L1/007 ,  H04L27/02 ,  H04L27/04 ,  H04L27/183 ,  H04L27/2602 ,  H04L27/2604 ,  H04L27/2608 ,  H04L27/34 ,  H04L27/3488 ,  H04L27/36 ,  H04L27/38 ,  H04L27/3854 ,  H04L2027/0036 ,  H04L2027/0053 ,  H04L2027/0067 ,  H04N5/4401 ,  H04N5/455 ,  H04N5/46 ,  H04N7/015 ,  H04N7/24 ,  H04N19/36 ,  H04N19/37 ,  H04N19/60 ,  H04N19/63 ,  H04N21/234327 ,  H04N21/2365 ,  H04N21/2383 ,  H04N21/4347 ,  H04N21/4382 ,  H04N21/440227 ,  H04N21/4621 ,  H04N21/64792

    摘要： At the transmitter side, carrier waves are modulated according to an input signal for producing relevant signal points in a signal space diagram. The input signal is divided into, two, first and second, data streams. The signal points are divided into signal point groups to which data of the first data stream are assigned. Also, data of the second data stream are assigned to the signal points of each signal point group. A difference in the transmission error rate between first and second data streams is developed by shifting the signal points to other positions in the space diagram expressed at least in the polar coordinate system. At the receiver side, the first and/or second data streams can be reconstructed from a received signal. In TV broadcast service, a TV signal is divided by a transmitter into, low and high, frequency band components which are designated as a first and a second data streams respectively. Upon receiving the TV signal, a receiver can reproduce only the low frequency band component or both the low and high frequency band components, depending on its capability. Furthermore, a communication system based on an OFDM system is utilized for data transmission of a plurality of subchannels, wherein the subchannels are differentiated by changing the length of a guard time slot or a carrier wave interval of a symbol transmission time slot, or changing the transmission electric power of the carrier.

    摘要翻译： 在发射机侧，根据用于在信号空间图中产生相关信号点的输入信号调制载波。 输入信号被分成两个，第一个和第二个数据流。 信号点被划分为分配了第一数据流的数据的信号点组。 此外，第二数据流的数据被分配给每个信号点组的信号点。 通过将信号点移动到至少在极坐标系中表示的空间图中的其他位置来开发第一和第二数据流之间的传输错误率的差异。 在接收机侧，可以从接收到的信号重建第一和/或第二数据流。 在电视广播业务中，电视信号由发射机分成低频和高频分量，分别被指定为第一和第二数据流。 在接收到TV信号时，接收机可以仅根据其能力再现低频带分量或低频和高频分量两者。 此外，基于OFDM系统的通信系统被用于多个子信道的数据传输，其中通过改变符号传输时隙的保护时隙或载波间隔的长度来区分子信道，或者改变 载波的传输电力。

    VSB/QAM receiver and method
    93.
    发明申请
    VSB/QAM receiver and method 失效
    VSB / QAM接收机和方法

    公开(公告)号：US20010048723A1

    公开(公告)日：2001-12-06

    申请号：US09794159

    申请日：2001-02-28

    发明人： Ji-sung Oh

    IPC分类号： H04L005/12 ,  H04L023/02 ,  H03D001/24

    CPC分类号： H04L27/0008 ,  H04L27/066 ,  H04L27/3854 ,  H04L2027/0036 ,  H04L2027/0055 ,  H04L2027/0087

    摘要： A vestigial sideband/quadrature amplitude modulation (VSB/QAM) receiver, which receives both VSB and QAM signals and restores a carrier wave with a restored symbol clock after restoring a symbol timing in a front portion of a carrier wave restoration unit. The receiver has an analog-digital converter for A/D converting in accordance with a frequency higher than a symbol frequency of a received signal; an interpolator for calculating a signal value on the original symbol location after a signal from the A/D converter is applied; the carrier wave restoration unit for restoring a carrier wave by selectively using an automatic frequency control (AFC) and a digital frequency phase locked loop (DFPLL) in accordance with a VSB/QAM mode after a signal from the interpolator is applied; a timing processor for receiving a signal from the carrier wave restoration unit, detecting a timing error after changing a symbol input time in accordance with a VSB/QAM mode, controlling the interpolator based on the detected timing error, and generating a restored clock; and a VSB sorter for extracting a VSB receiving symbol.

    摘要翻译： 一种残留边带/正交幅度调制（VSB / QAM）接收机，其在恢复载波恢复单元的前部中的符号定时之后接收VSB和QAM信号并恢复具有恢复的符号时钟的载波。 接收器具有用于根据接收信号的符号频率高的频率进行A / D转换的模数转换器; 用于在应用来自A / D转换器的信号之后计算原始符号位置上的信号值的内插器; 载波恢复单元，用于在应用来自内插器的信号之后，通过选择性地使用根据VSB / QAM模式的自动频率控制（AFC）和数字频率锁相环（DFPLL）来恢复载波; 定时处理器，用于从载波恢复单元接收信号，根据VSB / QAM模式检测符号输入时间改变后的定时误差，根据检测到的定时误差控制内插器，并产生恢复时钟; 以及用于提取VSB接收符号的VSB分类器。

    Demodulator
    95.
    发明授权
    Demodulator 失效
    解调器

    公开(公告)号：US6121828A

    公开(公告)日：2000-09-19

    申请号：US312986

    申请日：1999-05-17

    申请人： Eisaku Sasaki

    发明人： Eisaku Sasaki

    IPC分类号： H03D3/00 ,  H04B3/06 ,  H04L25/03 ,  H04L27/38

    CPC分类号： H04L27/3809 ,  H03D3/007 ,  H04L27/3854

    摘要： It is an object of the invention to provide a demodulator, which improves a BER characteristic in a ordinary state, reduce a time constant of a AGC amplifier, and quickly follows the fluctuation of an input signal level. A demodulator for 2.sup.q -QAM system is composed of an AGC amplifier, which keeps an average power of its output signal constant, A/D convectors for A/D converting the output signal of the AGC amplifier, an equalizer for removing interference components between codes contained in output signals of the A/D convectors, AGC circuits, which operate so that convergent points of output signals of the equalizer have amplitudes expressed by binary numbers composed of q/2 bits, and a control circuit, which is supplied with output signals of the AGC circuits and generates control signals for the AGC circuits.

    摘要翻译： 本发明的目的是提供一种解调器，其改善了普通状态下的BER特性，减小了AGC放大器的时间常数，并且迅速跟随输入信号电平的波动。 用于2q-QAM系统的解调器由AGC放大器组成，其保持其输出信号的平均功率恒定，用于A / D转换AGC放大器的输出信号的A / D对流器，用于去除代码之间的干扰分量的均衡器 包含在A / D对流体的AGC信号的输出信号中，AGC电路工作，使得均衡器的输出信号的收敛点具有由q / 2位组成的二进制数表示的幅度，以及控制电路，其被提供有输出信号 并产生用于AGC电路的控制信号。

    Digital communications system comprising a receiver that includes a timing recovery device
    96.
    发明授权
    Digital communications system comprising a receiver that includes a timing recovery device 失效
    数字通信系统，包括包括定时恢复装置的接收机

    公开(公告)号：US6049575A

    公开(公告)日：2000-04-11

    申请号：US132400

    申请日：1998-08-11

    申请人： Said Moridi

    发明人： Said Moridi

    IPC分类号： H04L7/00 ,  H04L7/02 ,  H04L27/38

    CPC分类号： H04L7/0062 ,  H04L27/3854 ,  H04L7/0083

    摘要： A digital communication system including a transmitter and a receiver and wherein transmitted digital signal samples are modulated in accordance with a first constellation of modulated signal values. The receiver includes a phase locked loop for synchronizing digital sampling at the receiver with the received signal samples. The synchronism adjustment error is formed from a pseudo-error function which is a weighted combination of first and second errors, the first error being a function of the distance between received samples and the decisions made with respect thereto in the first constellation, the second error being a function of the distance between received samples and the decisions made with respect thereto in a second simplified constellation derived from the first constellation. A weighting is assigned to the second error which may, in one embodiment, be proportional to the first error.

    摘要翻译： 一种包括发射机和接收机的数字通信系统，其中发射的数字信号样本根据调制信号值的第一星座进行调制。 接收机包括用于使接收机处的数字采样与接收的信号样本同步的锁相环。 同步调整误差由伪误差函数形成，伪误差函数是第一和第二误差的加权组合，第一误差是接收样本之间的距离和在第一星座中相对于其决定的函数的函数，第二误差 作为从第一星座导出的第二简化星座中的接收样本之间的距离和相对于其的决定的函数。 对第二误差分配加权，在一个实施例中可以与第一误差成正比。

    Methods and apparatus for reducing the effect of impulse noise on receivers
    97.
    发明授权
    Methods and apparatus for reducing the effect of impulse noise on receivers 失效
    减少脉冲噪声对接收机的影响的方法和装置

    公开(公告)号：US5867539A

    公开(公告)日：1999-02-02

    申请号：US505056

    申请日：1995-07-21

    申请人： Joshua L. Koslov

    发明人： Joshua L. Koslov

    IPC分类号： H03G3/34 ,  H04B1/10 ,  H04L27/06 ,  H04L27/38 ,  H03D1/06 ,  H04L1/00 ,  H04L27/22

    CPC分类号： H03G3/344 ,  H04L27/3854 ,  H04B1/1027

    摘要： Methods and apparatus for detecting the presence of impulse noise in a signal representing digital data and for performing a limiting or blanking operation in a receiver in response thereto are disclosed. In accordance with the present invention, to detect the presence of impulse noise, in one embodiment, the instantaneous sliced error energy for each received symbol is estimated and compared to either a predetermined threshold level indicative of impulse noise or to an adaptive impulse noise threshold level. In an adaptive impulse noise threshold embodiment, an adaptive impulse noise threshold value is generated by averaging the instantaneous sliced error energy values over a period of many symbols and by then applying a preselected gain to the averaged sliced error energy value to obtain an impulse noise threshold value. When impulse noise is detected a signal is asserted to indicate the detection and presence of the impulse noise and carrier recovery phase error correction operations and other decision dependent operations blanked or left unchanged until the impulse noise is no longer detected or for a preselected period of time after impulse noise has been detected.

    摘要翻译： 公开了用于在表示数字数据的信号中检测脉冲噪声的存在以及响应于接收机中进行限制或消隐操作的方法和装置。 根据本发明，为了检测脉冲噪声的存在，在一个实施例中，估计每个接收符号的瞬时分片误差能量，并将其与指示脉冲噪声的预定阈值电平或自适应脉冲噪声阈值电平进行比较 。 在自适应脉冲噪声阈值实施例中，自适应脉冲噪声阈值是通过在多个符号的周期上平均瞬时分片误差能量值，然后将预选增益应用于平均的分片误差能量值来产生的，以获得脉冲噪声阈值 值。 当检测到脉冲噪声时，信号被断言以指示脉冲噪声的检测和存在以及载波恢复相位误差校正操作和其他决定相关操作被消隐或保持不变，直到不再检测到脉冲噪声或者预选的时间段 在检测到脉冲噪声之后。

    Quadrature detector and amplitude error correction method for quadrature detector
    99.
    发明授权
    Quadrature detector and amplitude error correction method for quadrature detector 失效
    正交检波器的正交检波器和幅度误差校正方法

    公开(公告)号：US5787124A

    公开(公告)日：1998-07-28

    申请号：US751159

    申请日：1996-11-15

    申请人： Takashi Shimura

    发明人： Takashi Shimura

    IPC分类号： G01R25/04 ,  H03D1/22 ,  H03D3/00 ,  H04L27/22 ,  H04L27/38 ,  G06F7/44

    CPC分类号： H03D3/009 ,  H03D1/2245 ,  H04L27/3809 ,  H04L27/3854

    摘要： A method for correcting an amplitude error between an I signal and a Q signal which are outputted from a quadrature detector including a first multiplier for multiplying a reference signal and a measured signal, a first integrator for smoothing the output of the first multiplier to generate the I signal, a 90-degree phase shifter for generating an auxiliary reference signal from the reference signal, a second multiplier for multiplying the auxiliary reference signal and the measured signal, and a second integrator for smoothing the output of the second multiplier to generate the Q signal. The method includes the step of inputting the auxiliary reference signal, instead of the reference signal, to the first multiplier to obtain a first output signal and inputting the reference signal, instead of the auxiliary reference signal, to the second integrator to obtain a second output signal. Then a correction coefficient for amplitude error correction is calculated from at least one of a ratio between the Q signal and the first output signal and a ratio between the I signal and the second output signal.

    摘要翻译： 一种用于校正从包括用于乘以参考信号的第一乘法器和测量信号的正交检测器输出的I信号和Q信号之间的幅度误差的方法，用于平滑第一乘法器的输出的第一积分器， I信号，用于从参考信号产生辅助参考信号的90度移相器，用于将辅助参考信号和测量信号相乘的第二乘法器和用于平滑第二乘法器的输出以产生Q的第二积分器 信号。 该方法包括将辅助参考信号而不是参考信号输入到第一乘法器以获得第一输出信号并将参考信号而不是辅助参考信号输入到第二积分器以获得第二输出的步骤 信号。 然后，根据Q信号和第一输出信号之间的比率以及I信号和第二输出信号之间的比率中的至少一个来计算用于振幅误差校正的校正系数。

    System and method for transmitting sound and computer data
    100.
    发明授权
    System and method for transmitting sound and computer data 失效
    用于传输声音和计算机数据的系统和方法

    公开(公告)号：US5604771A

    公开(公告)日：1997-02-18

    申请号：US317721

    申请日：1994-10-04

    申请人： Robert Quiros

    发明人： Robert Quiros

    IPC分类号： H04L1/18 ,  H04L27/36 ,  H04L27/38 ,  H04L27/06 ,  H03D3/24

    CPC分类号： H04L27/3854 ,  H04L1/1803 ,  H04L27/362

    摘要： A system transmits computer data by converting and modulating the data into a sound file, allowing the sound file to be stored for later retrieval and transmission. The system includes a sound file creator for modulating input computer data and storing the data. In one embodiment the invention is used with a voice processing system, and can create data prompts, that are either stored or immediately transmitted to a screen telephone. The data prompts can include text and graphics for display on a remote screen telephone the connects to the voice processing system. The sound file creator uses a three layer communications protocol to translate the data into a data format, then modulates and equalizes the data for transmission over a telecommunications line. The data prompts are transmitted in response to a caller's inputs into the voice processing system. The transmitted data is received by a sound file receiver in a screen telephone, or like device, that demodulates the data and outputs to an appropriate display, printer or memory unit. Alternative embodiments of the invention include a facsimile like device for scanning, digitizing and transmitting input documents, and a system for outputting stored data from a memory unit such as a compact disc.

    摘要翻译： 系统通过将数据转换和调制成声音文件来传输计算机数据，允许声音文件被存储以用于稍后的检索和传输。 该系统包括用于调制输入计算机数据和存储数据的声音文件创建器。 在一个实施例中，本发明与语音处理系统一起使用，并且可以创建存储或立即传送到屏幕电话的数据提示。 数据提示可以包括用于在远程屏幕电话上显示的文本和图形，其连接到语音处理系统。 声音文件创建者使用三层通信协议将数据转换为数据格式，然后对数据进行调制和均衡，以便通过电信线进行传输。 响应于呼叫者的输入到语音处理系统中发送数据提示。 发送的数据由屏幕电话或类似设备中的声音文件接收器接收，其解调数据并输出到适当的显示器，打印机或存储器单元。 本发明的替代实施例包括用于扫描，数字化和传送输入文档的传真装置，以及用于从诸如光盘之类的存储单元输出存储的数据的系统。