Timing recovery using the pilot signal in high definition TV
    51.
    发明授权
    Timing recovery using the pilot signal in high definition TV 有权
    使用高分辨率电视中的导频信号进行定时恢复

    公开(公告)号:US06411659B1

    公开(公告)日:2002-06-25

    申请号:US09692805

    申请日:2000-10-20

    IPC分类号: H04L2714

    摘要: Improved carrier recovery and symbol timing systems and methods suitable for use in connection with a dual-mode QAM/VSB receiver system is disclosed. Carrier and symbol timing acquisition and tracking loops are phase/frequency locked to an inserted pilot signal provided in an input VSB spectrum at a given frequency. An input spectrum is centered about baseband and the pilot is extracted by an equivalent filter which functions as a bandpass filter having pass bands centered about the pilot frequency. Since the pilot signal's frequency is given, its position in the frequency domain for any sampling frequency, is deterministic. The receiver's sampling frequency is provided such that the relationship is expressed as fC=fS4. When tracked by a phase-lock loop, the pilot signal will appear at the correct location in the spectrum if the sampling frequency fS is correct, and will be shifted in one direction or the other if the sampling frequency fS is too high or too low.

    摘要翻译: 公开了适用于双模QAM / VSB接收机系统的改进的载波恢复和符号定时系统和方法。 载波和符号定时采集和跟踪环路被相位/频率锁定到在给定频率下在输入VSB频谱中提供的插入导频信号。 输入频谱以基带为中心,并且通过等效滤波器提取导频,该等效滤波器用作具有以导频频率为中心的通带的带通滤波器。 由于给出了导频信号的频率,所以在频域中对于任何采样频率的位置是确定性的。 提供接收机的采样频率,使得该关系表示为fC = fS4。 当通过锁相环路进行跟踪时,如果采样频率fS正确,则导频信号将出现在频谱中的正确位置,并且如果采样频率fS太高或太低,则导频信号将在一个方向或另一个方向上移位 。

    NTSC interference rejection filter
    52.
    发明授权
    NTSC interference rejection filter 有权
    NTSC干扰抑制滤波器

    公开(公告)号:US06344871B1

    公开(公告)日:2002-02-05

    申请号:US09685476

    申请日:2000-10-10

    IPC分类号: H04N538

    摘要: An electronic, programmable filter is disclosed which selectively removes interference, noise or distortion components from a frequency band without perturbing any of the other signals of the band. An input frequency band such as a television channel spectrum is initially demodulated to baseband and applied to the input of the filter. The baseband spectrum is combined in a complex mixer with a synthesized frequency signal that shifts the spectrum a characteristic amount, in the frequency domain, so as to position an interference component in the region about DC. Once shifted, the frequency components about DC are removed by DC canceler circuit and the resulting spectrum is mixed with a subsequent synthesized frequency signal which shifts the spectrum back to its original representation and baseband. The frequency signals are developed by a programmable frequency synthesizer which a user may program with an intelligence signal that defines the frequency location of an interference signal within the spectrum. Filter blocks may be added or subtracted in order to optimize the filter response for any number of interference components for which rejection is desired.

    摘要翻译: 公开了一种电子可编程滤波器,其选择性地从频带中去除干扰,噪声或失真分量,而不扰乱频带的任何其它信号。 诸如电视频道频谱的输入频带最初被解调为基带并且被应用于滤波器的输入。 基带频谱在复合混频器中与合成频率信号组合,该频率信号在频域中使频谱偏移特征量,以便在DC周围的区域中定位干扰分量。 一旦移位,DC直流的频率分量被直流消除器电路去除,所得到的频谱与随后的合成频率信号混合,后者将频谱转移回原来的表示和基带。 频率信号由可编程频率合成器开发,用户可以使用定义频谱内的干扰信号的频率位置的智能信号进行编程。 可以添加或减少滤波器块以优化对于期望的抑制的任何数量的干扰分量的滤波器响应。

    NTSC interference rejection filter
    53.
    发明授权
    NTSC interference rejection filter 有权
    NTSC干扰抑制滤波器

    公开(公告)号:US06219088B1

    公开(公告)日:2001-04-17

    申请号:US09303783

    申请日:1999-04-30

    IPC分类号: H04N538

    摘要: An electronic, programmable filter is disclosed which selectively removes interference, noise or distortion components from a frequency band without perturbing any of the other signals of the band. An input frequency band such as a television channel spectrum is initially demodulated to baseband and applied to the input of the filter. The baseband spectrum is combined in a complex mixer with a synthesized frequency signal that shifts the spectrum a characteristic amount, in the frequency domain, so as to position an interference component in the region about DC. Once shifted, the frequency components about DC are removed by DC canceler circuit and the resulting spectrum is mixed with a subsequent synthesized frequency signal which shifts the spectrum back to its original representation and baseband. The frequency signals are developed by a programmable frequency synthesizer which a user may program with an intelligence signal that defines the frequency location of an interference signal within the spectrum. Filter blocks may be added or subtracted in order to optimize the filter response for any number of interference components for which rejection is desired.

    摘要翻译: 公开了一种电子可编程滤波器,其选择性地从频带中去除干扰,噪声或失真分量,而不扰乱频带的任何其它信号。 诸如电视频道频谱的输入频带最初被解调为基带并且被应用于滤波器的输入。 基带频谱在复合混频器中与合成频率信号组合,该频率信号在频域中将频谱偏移特征量,以便在DC周围的区域中定位干扰分量。 一旦移位,DC直流的频率分量被直流消除器电路去除,所得到的频谱与随后的合成频率信号混合,后者将频谱转移回原来的表示和基带。 频率信号由可编程频率合成器开发,用户可以使用定义频谱内的干扰信号的频率位置的智能信号进行编程。 可以添加或减少滤波器块以优化对于期望的抑制的任何数量的干扰分量的滤波器响应。

    Universal network interface module
    54.
    发明授权
    Universal network interface module 失效
    通用网络接口模块

    公开(公告)号:US06169767A

    公开(公告)日:2001-01-02

    申请号:US09036925

    申请日:1998-03-09

    IPC分类号: H04L2712

    CPC分类号: H04L27/0008

    摘要: A variable rate modulator for selectively encoding a variable rate data stream according to one of a plurality of modulation formats. A timing and control circuit locks the variable rate data to a master clock, an encoder selectively encodes the data according to one of a plurality of modulation formats, and a polyphase filter performs pulse shaping and interpolation functions using only shift and add functions to produce a DAC-ready output signal.

    摘要翻译: 一种可变速率调制器,用于根据多种调制格式之一选择性地编码可变速率数据流。 定时和控制电路将可变速率数据锁定到主时钟,编码器根据多种调制格式之一选择性地对数据进行编码,并且多相滤波器仅使用移位和加法函数来执行脉冲整形和插值功能,以产生 DAC就绪输出信号。

    Multiple modulation format television signal receiver system
    55.
    发明授权
    Multiple modulation format television signal receiver system 失效
    多调制格式电视信号接收系统

    公开(公告)号:US6005640A

    公开(公告)日:1999-12-21

    申请号:US721867

    申请日:1996-09-27

    摘要: A television receiver for processing both analog television signals and digital television signals. Specifically, the television receiver contains a RF/IF front end, an analog-to-digital converter that samples a near baseband signal using a "free running" sample rate, and a combined demodulator that demodulates the digitized analog television signals or the sampled digital television signals. The combined demodulator recovers both pilot and pix carriers as well as provide a passband adaptive equalizer that removes ghosts from analog television signals and intersymbol interference from digital television signals.

    摘要翻译: 一种用于处理模拟电视信号和数字电视信号的电视接收机。 具体来说,电视接收机包含RF / IF前端,使用“自由运行”采样率对近基带信号进行采样的模/数转换器,以及解调数字化模拟电视信号或采样数字 电视信号。 组合的解调器恢复导频和像素载波,并提供通带自适应均衡器,其从模拟电视信号中消除重影,并从数字电视信号中产生码间干扰。

    Numerical voltage controlled oscillator
    56.
    发明授权
    Numerical voltage controlled oscillator 失效
    数字压控振荡器

    公开(公告)号:US5619154A

    公开(公告)日:1997-04-08

    申请号:US541911

    申请日:1995-10-10

    摘要: A numerical voltage controlled oscillator comprising an integrator for generating an estimated sine waveform and an estimated cosine waveform from a variable control signal; a normalizer, connected to the integrator, for generating a normalization factor from the estimated sine waveform and the estimated cosine waveform; and a multiplier, connected to the normalizer, for multiplying the normalization factor with the estimated sine waveform and the estimated cosine waveform. The multiplication of the estimated sine waveform and the normalization factor produces the sine waveform and the multiplication of the estimated cosine waveform and the normalization factor produces the cosine waveform. The frequency and phase of the sine and cosine waveforms vary with changes in amplitude of the variable control signal.

    摘要翻译: 一种数字压控振荡器,包括用于从可变控制信号产生估计正弦波形和估计余弦波形的积分器; 连接到积分器的归一化器,用于根据估计的正弦波形和估计的余弦波形产生归一化因子; 以及连接到归一化器的乘法器,用于将归一化因子与估计的正弦波形和估计的余弦波形相乘。 估计的正弦波形和归一化因子的乘积产生正弦波形,并且估计的余弦波形和归一化因子的乘积产生余弦波形。 正弦和余弦波形的频率和相位随可变控制信号的幅度变化而变化。

    Single oscillator compressed digital information receiver
    57.
    发明授权
    Single oscillator compressed digital information receiver 失效
    单振压缩数字信息接收机

    公开(公告)号:US5588025A

    公开(公告)日:1996-12-24

    申请号:US406216

    申请日:1995-03-15

    摘要: A digital information receiver having a single oscillator providing a clock signal to the receiver circuitry. The receiver contains, in addition to the oscillator, an input signal processor, a symbol timing loop, a demodulator, a transport decoder, a transport timing loop, one or more applications decoders and a presentation device. The input signal processor digitizes an input signal and resamples the input signal using an interpolator such that the input signal is optimally sampled. The resampling is controlled by a symbol timing loop. In a first embodiment, the transport timing loop controls the frequency of the oscillator using transmitter timing information contained in the received signal. In a second embodiment, the oscillator is a free running oscillator and the transport timing loop controls a numerically controlled counter that, in turn, controls presentation timing of the information carried by the information in the input signal. After the input signal is decoded, an output interpolator generates continuous signals from somewhat bursty signals for utilization by the presentation device.

    摘要翻译: 一种数字信息接收机,具有向接收机电路提供时钟信号的单个振荡器。 除了振荡器之外,接收器还包含输入信号处理器,符号定时环路,解调器,传输解码器,传输定时环路,一个或多个应用解码器和呈现设备。 输入信号处理器对输入信号进行数字化并且使用内插器对输入信号进行再采样,使得输入信号被最佳地采样。 重采样由符号定时循环控制。 在第一实施例中,传输定时环路使用包含在接收信号中的发射机定时信息来控制振荡器的频率。 在第二实施例中,振荡器是自由运行的振荡器,并且传输定时循环控制数字控制的计数器,其又控制由输入信号中的信息携带的信息的呈现定时。 在输入信号被解码之后,输出内插器从一些突发信号产生连续的信号,以供呈现设备利用。

    Data placement on tape for a digital video tape recorder suitable for
high speed picture playback
    58.
    发明授权
    Data placement on tape for a digital video tape recorder suitable for high speed picture playback 失效
    适用于高速图像播放的数字录像机的磁带上的数据放置

    公开(公告)号:US5398143A

    公开(公告)日:1995-03-14

    申请号:US983741

    申请日:1992-12-01

    摘要: An image carrier for storing video information including a plurality of slant tracks recorded thereon, wherein each of the tracks is characterized as including a predetermined number of sync blocks defining a predetermined track length, wherein each of the sync blocks is divided into first and second portions storing respective first and second digital signals coded therein. The first digital signal permits reconstruction of an input image during a trickplay mode of operation while the second digital signal permits reconstruction of an input image with a comparable resolution during a normal play mode of operation. On the average, the first digital signal of each sync block represents a complete scan line of the input image.

    摘要翻译: 一种用于存储包括记录在其上的多个倾斜轨道的视频信息的图像载体,其中每个轨道的特征在于包括预定数量的定义预定轨道长度的同步块,其中每个同步块被分成第一和第二部分 存储其中编码的相应的第一和第二数字信号。 第一数字信号允许在特技播放操作模式期间重建输入图像,而第二数字信号允许在正常播放操作模式期间以相当的分辨率重建输入图像。 平均而言,每个同步块的第一个数字信号表示输入图像的完整扫描线。