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    Hybrid equalizer arrangement for use in data communications equipment
    2.
    发明授权
    Hybrid equalizer arrangement for use in data communications equipment 失效
    用于数据通信设备的混合均衡器布置

    公开(公告)号：US5513216A

    公开(公告)日：1996-04-30

    申请号：US322877

    申请日：1994-10-13

    申请人： Shlomo Gadot ,  Gi-Hong Im ,  Ehud Langberg ,  Jin-Der Wang

    发明人： Shlomo Gadot ,  Gi-Hong Im ,  Ehud Langberg ,  Jin-Der Wang

    IPC分类号： H03H21/00 ,  H04B3/14 ,  H04L25/03 ,  H04L25/497 ,  H04L27/01

    CPC分类号： H04L25/4975 ,  H04L25/03057 ,  H04L25/03343 ,  H04L25/497 ,  H04L2025/03503 ,  H04L2025/03808

    摘要： A hybrid type of decision feedback equalizer (DFE) structure that approaches optimal DFE performance is described. The hybrid DFE includes both an intersymbol interference DFE (ISI-DFE) and a noise predictive DFE (NP-DFE). The hybrid DFE structure is designed so that one form of tap values dominates over the other. This allows only the dominate tap values to be used by the transmitter during precoding and reduces the transmitter complexity. In particular, a hybrid DFE is designed so that the I(z) coefficient values dominate over the N(z) coefficient values, where the notation I(z) and N(z), as known in the art, represent the resulting coefficient values after adaptation of the ISI-DFE and the NP-DFE, respectively. A respective Tomlinson precoding scheme in the transmitter uses only the I(z) values. Since only the I(z) values are used in the precoder of the transmitter, the NP-DFE of the receiver is kept active during the communications phase. Conveniently, the continued use of the NP-DFE in the receiver allows the receiver to track small changes in the channel.

    摘要翻译： 描述了接近最优DFE性能的混合型判决反馈均衡器（DFE）结构。 混合DFE包括符号间干扰DFE（ISI-DFE）和噪声预测DFE（NP-DFE）。 混合DFE结构被设计成使得一种形式的抽头值占主导地位。 这只允许发射机在预编码期间使用主要抽头值，并降低发射机的复杂度。 特别地，混合DFE被设计为使得I（z）系数值在N（z）系数值上占优势，其中本领域已知的符号I（z）和N（z）表示所得系数 分别适应ISI-DFE和NP-DFE后的值。 发射机中各自的Tomlinson预编码方案仅使用I（z）值。 由于在发射机的预编码器中仅使用I（z）值，因此接收机的NP-DFE在通信阶段保持有效。 方便地，在接收机中继续使用NP-DFE允许接收机跟踪信道中的小变化。

    System and method producing improved frame synchronization in a digital communication system
    3.
    发明授权
    System and method producing improved frame synchronization in a digital communication system 失效
    在数字通信系统中产生改进的帧同步的系统和方法

    公开(公告)号：US5748686A

    公开(公告)日：1998-05-05

    申请号：US628220

    申请日：1996-04-04

    申请人： Ehud Langberg ,  Jin-Der Wang

    发明人： Ehud Langberg ,  Jin-Der Wang

    IPC分类号： H04H20/46 ,  H04H20/72 ,  H04H40/27 ,  H04J3/06 ,  H04L25/03 ,  H04L7/00

    CPC分类号： H04H20/46 ,  H04H40/27 ,  H04L25/03133 ,  H04H20/72 ,  H04H2201/20 ,  H04L7/08

    摘要： In a digital audio broadcasting (DAB) system having a radio-frequency (RF) transmitter and a corresponding RF receiver, a system and method for providing improved frame synchronization is provided. In accordance with the preferred embodiment, the RF transmitter formats a DAB signal into a sequence of frames, each frame having a header with a predefined grouping of psuedo-random number sequences comprising 100 symbols. Of these 100 symbols, 86 symbols of the header preferable are used for frame synchronization and characterization of a communications channel, while the remaining 14 symbols are used for interleaver and data synchronization in an interleaved fashion. The formatted DAB signal, including the frame sequences, is transmitted to the receiver preferably using quadrature phase-shift keying modulation. At the receiver, a correlator, utilizing a synchronization detection algorithm, is generally designed to match a predetermined symbol pattern within the received signal. Once the frame synchronization is established, the channel is characterized and the data symbols are recovered.

    摘要翻译： 在具有射频（RF）发射机和对应的RF接收机的数字音频广播（DAB）系统中，提供了一种用于提供改进的帧同步的系统和方法。 根据优选实施例，RF发射机将DAB信号格式化成帧序列，每帧具有包含100个符号的伪随机数序列的预定义分组的报头。 在这100个符号中，优选的标题的86个符号用于通信信道的帧同步和表征，而剩余的14个符号以交织方式用于交织器和数据同步。 包括帧序列的格式化的DAB信号优选地使用正交相移键控调制发送到接收机。 在接收机处，通常设计利用同步检测算法的相关器，以匹配接收信号内的预定码元模式。 一旦建立了帧同步，就对信道进行表征，并恢复数据符号。

    Technique for improving the operation of decision feedback equalizers in communications systems utilizing error correction
    4.
    发明授权
    Technique for improving the operation of decision feedback equalizers in communications systems utilizing error correction 失效
    利用纠错通信系统改善决策反馈均衡器运行的技术

    公开(公告)号：US5052000A

    公开(公告)日：1991-09-24

    申请号：US363793

    申请日：1989-06-09

    申请人： Jin-Der Wang ,  Jean-Jacques Werner

    发明人： Jin-Der Wang ,  Jean-Jacques Werner

    IPC分类号： H04B3/06 ,  H04L1/00 ,  H04L25/03 ,  H04L25/06 ,  H04L27/34

    CPC分类号： H04L1/0059 ,  H04L1/0047 ,  H04L1/0065 ,  H04L1/0066 ,  H04L25/03057 ,  H04L25/063 ,  H04L27/3438

    摘要： The combined benefits of decision feedback equalization and error correction coding are realized in a communications system by the use of a plurality of coders and decoders respectively disposed in the transmitter and receiver. The plurality of encoders and decoders is used to interleave the data symbols so that each coder and decoder is operative upon every Mth symbol, where M is the number of coders or decoders. By a judicious choice of M, both the probability of noise impairing the recovery of successive symbols and the error propagation effects inherent in decision feedback equalizers are reduced.

    摘要翻译： 在通信系统中通过使用分别设置在发射机和接收机中的多个编码器和解码器来实现判决反馈均衡和纠错编码的组合优点。 多个编码器和解码器用于交织数据符号，使得每个编码器和解码器在每第M个符号上操作，其中M是编码器或解码器的数量。 通过M的明智选择，降低了连续符号恢复的噪声概率和决策反馈均衡器固有的误差传播效应。

    Decoding technique in discrete multi-tone (DMT) based communications systems
    5.
    发明授权
    Decoding technique in discrete multi-tone (DMT) based communications systems 失效
    基于离散多音（DMT）的通信系统中的解码技术

    公开(公告)号：US06628722B1

    公开(公告)日：2003-09-30

    申请号：US09100615

    申请日：1998-06-19

    申请人： Rajiv Laroia ,  Jin-Der Wang

    发明人： Rajiv Laroia ,  Jin-Der Wang

    IPC分类号： H04L7700

    CPC分类号： H04L27/2602 ,  H04L1/08 ,  H04L27/2614 ,  H04L27/2624

    摘要： In an Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone (DMT) system, ADSL DMT equipment includes a decoder that operates on a received DMT signal representing Nf symbols/second, where N>1, to recover f symbols per second. In particular, the decoder decides each symbol value of the recovered signal as a function of values of a respective 2N symbol values from the received DMT signal.

    摘要翻译： 在非对称数字用户环路（ADSL）离散多音（DMT）系统中，ADSL DMT设备包括一个解码器，它对接收到的表示Nf个符号/秒的DMT信号进行操作，其中N≥1，每秒恢复f个符号。 具体地，解码器根据接收到的DMT信号，将恢复信号的每个符号值作为2N个符号值的值的函数。

    Hybrid equalizer arrangement for use in data communications equipment
    9.
    发明授权
    Hybrid equalizer arrangement for use in data communications equipment 失效
    用于数据通信设备的混合均衡器布置

    公开(公告)号：US5604769A

    公开(公告)日：1997-02-18

    申请号：US322878

    申请日：1994-10-13

    申请人： Jin-Der Wang

    发明人： Jin-Der Wang

    IPC分类号： H04B3/04 ,  H03H21/00 ,  H04B3/06 ,  H04B3/14 ,  H04B14/00 ,  H04L25/03 ,  H04L25/497 ,  H04L27/01

    CPC分类号： H04L25/4975 ,  H04L25/03057 ,  H04L25/03343 ,  H04L25/497 ,  H04L2025/03503 ,  H04L2025/03808

    摘要： A hybrid type of decision feedback equalizer (DFE) structure that approaches optimal DFE performance is described. The hybrid DFE includes both an intersymbol interference DFE (ISI-DFE) and a noise predictive DFE (NP-DFE). In particular, an adaptive feedforward filter section is followed by both an intersymbol interference (ISI) predictive filter and a noise predictive (NP) filter. The corresponding transmitter uses a precoder that utilizes optimal coefficient values, denoted as C(z), of the hybrid DFE structure. In particular, C(z) is equal to (1+I(z)) (1+N(z))-1, where, the notation I(z) and N(z), as known in the art, represent the resulting coefficient values after adaptation of the ISI-DFE and the NP-DFE, respectively.

    摘要翻译： 描述了接近最优DFE性能的混合型判决反馈均衡器（DFE）结构。 混合DFE包括符号间干扰DFE（ISI-DFE）和噪声预测DFE（NP-DFE）。 特别地，自适应前馈滤波器部分之后是符号间干扰（ISI）预测滤波器和噪声预测（NP）滤波器。 相应的发射机使用预混合器，该预编码器利用混合DFE结构的最佳系数值（表示为C（z））。 特别地，C（z）等于（1 + I（z））（1 + N（z））-1，其中，本领域已知的符号I（z）和N（z） 分别在ISI-DFE和NP-DFE适配后产生的系数值。

    Signal correlation technique
    10.
    发明授权
    Signal correlation technique 失效
    信号相关技术

    公开(公告)号：US5406586A

    公开(公告)日：1995-04-11

    申请号：US89153

    申请日：1993-07-08

    申请人： Jin-Der Wang

    发明人： Jin-Der Wang

    IPC分类号： G06F17/15 ,  H04L25/02 ,  H04L27/06

    CPC分类号： H04L25/0202 ,  G06F17/153

    摘要： The present invention relates to correlation apparatus in which samples of a received signal are demultiplexed and coupled to a plurality of correlators in cyclic fashion so that successive samples are coupled to a different correlator in the plurality. Each correlator provides an output which is coupled to multiplexing apparatus. This apparatus is especially useful for determining signal dispersion characteristics and avoids the "null taps" associated with conventional correlation apparatus.

    摘要翻译： 本发明涉及相关装置，其中接收信号的样本被解复用并且以循环方式耦合到多个相关器，使得连续采样被耦合到多个不同的相关器。 每个相关器提供耦合到多路复用装置的输出。 该装置对于确定信号色散特性特别有用，并且避免了与常规相关装置相关联的“零抽头”。