公开(公告)号：US06661848B1

公开(公告)日：2003-12-09

申请号：US09160569

申请日：1998-09-25

申请人： Wesley Smith ,  Karl Nordling ,  Amir Hindie ,  Karl Leinfelder ,  Sebastian Gracias ,  Jim Beaney

发明人： Wesley Smith ,  Karl Nordling ,  Amir Hindie ,  Karl Leinfelder ,  Sebastian Gracias ,  Jim Beaney

IPC分类号： H04K110

CPC分类号： H04L12/66

摘要： An audio modem provides both the functionality needed for audio processing and that needed for implementing one or more modems. A digital signal processor utilizes a plurality of serial ports to interface with one or more codecs used for interfacing an analog audio channel and with one or more modem codecs used for interfacing an analog communications channel.

摘要翻译： 音频调制解调器提供音频处理所需的功能和实现一个或多个调制解调器所需的功能。 数字信号处理器利用多个串行端口与用于接口模拟音频信道的一个或多个编解码器以及用于接口模拟通信信道的一个或多个调制解调器编解码器进行接口。

公开(公告)号：US06631167B1

公开(公告)日：2003-10-07

申请号：US09593842

申请日：2000-06-14

申请人： Joël Cambonie ,  Philippe Mejean ,  Dominique Barthel ,  Joël Lienard

发明人： Joël Cambonie ,  Philippe Mejean ,  Dominique Barthel ,  Joël Lienard

IPC分类号： H04K110

CPC分类号： G06T1/60 ,  H04L27/265

摘要： The post-processing of the transformation processing of an interleaved type is temporally nested with regards to two successive symbols, and includes storage in two separately addressable memories of identical size. The addressing of the two memories is performed successively and alternately in the natural and reverse order at the frequency with the symbol clock signal.

摘要翻译： 交织类型的变换处理的后处理关于两个连续的符号在时间上嵌套，并且包括在相同大小的两个可单独寻址的存储器中的存储。 这两个存储器的寻址以符号时钟信号的频率以自然和相反的顺序连续地或交替地执行。

公开(公告)号：US06298035B1

公开(公告)日：2001-10-02

申请号：US09468313

申请日：1999-12-21

申请人： Juha Heiskala

发明人： Juha Heiskala

IPC分类号： H04K110

CPC分类号： H04L27/2647 ,  H04L25/0204 ,  H04L2025/03414 ,  H04L2025/03624

摘要： A method and apparatus for estimating separate channel frequency responses for two channels in an orthogonal frequency division multiplexing system with two transmitters is disclosed. The channel frequency responses are estimated using specifically selected training symbols that are broadcast from the two transmitters. The training symbols are specifically selected so as to improve the estimation of the channel frequency responses for each channel, while requiring the same amount of training symbols as in an estimation of the channel frequency response of a single channel.

摘要翻译： 公开了一种用于在具有两个发射机的正交频分复用系统中估计用于两个信道的单独信道频率响应的方法和装置。 使用从两个发射机广播的特定选择的训练符号来估计信道频率响应。 具体地选择训练符号，以便改进每个信道的信道频率响应的估计，同时要求与单个信道的信道频率响应的估计中相同量的训练符号。

公开(公告)号：US06292515B1

公开(公告)日：2001-09-18

申请号：US09510578

申请日：2000-02-22

申请人： Chiihsin Kao ,  Chunta Chen ,  Ming-Kang Liu

发明人： Chiihsin Kao ,  Chunta Chen ,  Ming-Kang Liu

IPC分类号： H04K110

CPC分类号： H04L27/2608

摘要： A circuit and method that optimizes and adapts the bit and energy configurations of data sub-channels in a multi-channel data transmission signal is disclosed. A high speed system can select either of a first or a second adaptation routine to handle changes in the bit and gain loadings of sub-channel carriers based on line disturbances or transmission change requests, based on which is most aptly suited to handle the particular change. In a preferred embodiment the resulting bit/energy loadings can be adjusted to be fully compliant with applicable Discrete Multi-Tone (DMT) implementations of Asymmetric Digital Subscriber Loop (ADSL) protocols.

摘要翻译： 公开了一种在多通道数据传输信号中优化和适应数据子通道的位和能量配置的电路和方法。 高速系统可以基于线路干扰或传输变化请求，选择第一或第二适配例程中的任何一个来处理子信道载波的位变化和增益负载，基于哪一个最适合于处理特定变化 。 在优选实施例中，所得到的比特/能量负载可以被调整为完全符合非对称数字用户环路（ADSL）协议的适用的离散多音（DMT）实现。

公开(公告)号：US06185257B2

公开(公告)日：2001-02-06

申请号：US09029529

申请日：1998-02-27

申请人： Timothy J. Moulsley

发明人： Timothy J. Moulsley

IPC分类号： H04K110

CPC分类号： H04L27/2649 ,  H04L27/2627

摘要： A transmission system for the transmission of a signal having a number of carriers provides a simplified demodulation function. The simplification is achieved by reducing the quantity of arithmetic operations that are required, particularly when only one or a few channels have to be received and demodulated.

摘要翻译： 用于发送具有多个载波的信号的传输系统提供简化的解调功能。 通过减少所需的算术运算的数量来实现简化，特别是当只有一个或几个信道必须被接收和解调时。

公开(公告)号：US06633616B2

公开(公告)日：2003-10-14

申请号：US09935081

申请日：2001-08-21

申请人： James A. Crawford

发明人： James A. Crawford

IPC分类号： H04K110

CPC分类号： H04L27/2657 ,  H04L27/2675 ,  H04L27/2679 ,  H04L2027/0067 ,  H04L2027/0087

摘要： A pilot phase tracking loop for an OFDM receiver including a phase rotator receiving an incoming signal, a fast Fourier transform coupled to a phase rotator output, and a pilot phase error metric including a discrete Fourier transform portion coupled to the phase rotator output. The pilot phase error metric determines a phase error estimate associated with a received OFDM symbol, e.g., a data symbol, from the phase rotator output. A loop filter is coupled to the pilot phase error metric output and an oscillator is coupled to the loop filter output. The oscillator output is coupled to the phase rotator to adjust the phase of subsequent OFDM symbols of the incoming signal. Phase noise introduced by a radio portion of the OFDM receiver and OFDM transmitter is reduced by the baseband portion of the OFDM receiver improving OFDM signal tracking under poor SNR conditions.

摘要翻译： 用于OFDM接收机的导频相位跟踪环路，包括接收输入信号的相位旋转器，耦合到相位旋转器输出的快速傅里叶变换，以及包括耦合到相位旋转器输出的离散傅立叶变换部分的导频相位误差度量。 导频相位误差度量确定与来自相位旋转器输出的接收的OFDM符号（例如，数据符号）相关联的相位误差估计。 环路滤波器耦合到导频相位误差度量输出，并且振荡器耦合到环路滤波器输出。 振荡器输出耦合到相位旋转器以调整输入信号的后续OFDM符号的相位。 由OFDM接收机和OFDM发射机的无线电部分引入的相位噪声由OFDM接收机的基带部分减小，在差的SNR条件下改善OFDM信号跟踪。

公开(公告)号：US06452977B1

公开(公告)日：2002-09-17

申请号：US09153637

申请日：1998-09-15

申请人： Don Roy Goldston ,  David Carl Hartup ,  Marcus McLenn Matherne

发明人： Don Roy Goldston ,  David Carl Hartup ,  Marcus McLenn Matherne

IPC分类号： H04K110

CPC分类号： H04H20/30 ,  H04L5/023 ,  H04L27/2613

摘要： A broadcasting method for simultaneously broadcasting analog and digital signals in a standard AM broadcasting channel is provided by: broadcasting an amplitude modulated radio frequency signal having a first frequency spectrum, wherein the amplitude modulated radio frequency signal includes a first carrier at a frequency of f0 modulated by an analog program signal representative of program material; and simultaneously broadcasting a plurality of digitally modulated orthogonal frequency division multiplexed carrier signals within a frequency range of about f0±15 kHz, which encompasses the first frequency spectrum, each of the digitally modulated carrier signals being modulated by a portion of a digital program signal, wherein the digital signal includes a digital representation of the program material, additional data, or a combination of the program material and the additional data. A first group of the digitally modulated carrier signals lying within the first frequency spectrum are modulated in-quadrature with the first carrier signal, and second and third groups of the digitally modulated carrier signals lie outside of the first frequency spectrum and are modulated both in-phase and in-quadrature with the first carrier signal. A training sequence of known data is periodically transmitted using selected ones of the digitally modulated carrier signals. Transmitters and receivers which operate in accordance with the above method are also provided.

摘要翻译： 通过以下方式提供在标准AM广播频道中同时广播模拟和数字信号的广播方法：广播具有第一频谱的幅度调制射频信号，其中调幅射频信号包括频率为f0调制的第一载波 通过代表节目素材的模拟节目信号; 并且同时在包含第一频谱的大约f0±15kHz的频率范围内广播多个数字调制的正交频分复用载波信号，每个数字调制载波信号由数字节目信号的一部分调制， 其中所述数字信号包括所述节目素材的数字表示，附加数据，或所述节目素材和所述附加数据的组合。 位于第一频谱内的第一组数字调制载波信号与第一载波信号进行正交调制，第二和第三组数字调制载波信号位于第一频谱之外， 与第一载波信号相位和正交。 使用所选择的数字调制载波信号周期性地发送已知数据的训练序列。 还提供了根据上述方法操作的发射机和接收机。

公开(公告)号：US06389137B1

公开(公告)日：2002-05-14

申请号：US08951027

申请日：1997-10-15

申请人： Takehiro Sugita ,  Akira Ogino ,  Takashi Usui

发明人： Takehiro Sugita ,  Akira Ogino ,  Takashi Usui

IPC分类号： H04K110

CPC分类号： H04N5/913 ,  H04N2005/91314 ,  H04N2005/91321 ,  H04N2005/91328 ,  H04N2005/9135

摘要： A playback device generates a Pseudo-random noise (PN) code sequence repeatedly with a predetermined period in synchronism with a video sync signal. An anti-duplication control signal is spectrally spread using this generated PN code sequence, is superimposed on the video signal, and is output. A PN code sequence having the same timing and code pattern as the PN code sequence used in the playback device is similarly generated based on the video sync signal on the receiving side which receives the output video signal. Using this PN code sequence, reverse spectral spread is performed, the anti-duplication control signal superimposed on the video signal is extracted, and anti-duplication control is performed according to the extracted anti-duplication control signal.

摘要翻译： 重放装置与视频同步信号同步地以预定周期重复产生伪随机噪声（PN）码序列。 使用该生成的PN码序列对反复制控制信号进行频谱扩展，叠加在视频信号上并被输出。 基于接收到输出视频信号的接收侧的视频同步信号，类似地产生具有与重放装置中使用的PN码序列相同的定时和码型的PN码序列。 使用该PN码序列，执行反向频谱扩展，提取叠加在视频信号上的反复制控制信号，并根据提取的反复制控制信号进行反复制控制。

公开(公告)号：US06304611B1

公开(公告)日：2001-10-16

申请号：US09099390

申请日：1998-06-18

申请人： Atsushi Miyashita ,  Toshiyuki Akiyama ,  Seiichi Sano ,  Nobuo Tsukamoto ,  Tatuhiro Nakada

发明人： Atsushi Miyashita ,  Toshiyuki Akiyama ,  Seiichi Sano ,  Nobuo Tsukamoto ,  Tatuhiro Nakada

IPC分类号： H04K110

CPC分类号： H04L27/2607 ,  H04L27/2626

摘要： An orthogonal frequency division multiplex (OFDM) modulator of such a system as to add guard intervals to a temporal waveform generated by modulating an input data train into a large number of (sub)carriers, conducting quadrature modulation, and outputting an OFDM signal. The OFDM modulator includes an IFFT circuit for conducting inverse fast Fourier transform processing to modulate the input data train into a large number of (sub)carriers, a guard interval adder for adding a guard interval to each effective symbol duration of a composite carrier signal supplied from the IFFT circuit and outputting a resultant signal, a control signal generator for generating, in synchronism with each guard interval of the composite carrier signal having the guard intervals added thereto, such a control signal as to attenuate signal amplitude of the composite carrier signal over an interval substantially equal in length to each guard interval; and an amplitude controller, responsive to the control signal, to attenuate the amplitude of the composite carrier signal supplied from the guard interval adder and output a resultant signal, only over an interval substantially equal in length to each guard interval. The amplitude controller outputting, in remaining intervals, the composite carrier signal supplied from the guard interval adder as it is.

摘要翻译： 这种系统的正交频分复用（OFDM）调制器，用于通过将输入数据串调制成大量（子）载波，进行正交调制并输出OFDM信号而产生的时间波形增加保护间隔。 OFDM调制器包括用于进行快速傅立叶逆变换逆变换处理以将输入数据串调制成大量（子）载波的IFFT电路，用于将提供的复合载波信号的每个有效符号持续时间加上保护间隔的保护间隔加法器 从IFFT电路输出结果信号，控制信号发生器，与与其相加的保护间隔的复合载波信号的每个保护间隔同步地产生一个控制信号，以便衰减复合载波信号的信号幅度 长度与每个保护间隔基本相等的间隔; 以及振幅控制器，响应于控制信号，衰减从保护间隔加法器提供的复合载波信号的振幅，并输出结果信号，仅在长度上与每个保护间隔基本相等的间隔上。 幅度控制器以剩余的间隔输出从保护间隔加法器原样提供的复合载波信号。

公开(公告)号：US06222888B1

公开(公告)日：2001-04-24

申请号：US09510118

申请日：2000-02-22

申请人： Chiihsin Kao ,  Chunta Chen ,  Ming-Kang Liu

发明人： Chiihsin Kao ,  Chunta Chen ,  Ming-Kang Liu

IPC分类号： H04K110

CPC分类号： H04L27/2608

摘要： A circuit and method that optimizes a set up time and control of bit and energy loadings of data sub-channels in a multi-channel data transmission signal is disclosed. A time out period, or an iteration count are used to control a setup time. An initialization routine attempts to make appropriate loadings within such time out period or within an iteration count parameter. If it is unable to do so, a handoff is made to a second routine to complete the loadings. In a preferred embodiment the initialization routine calculates rough parameters, while the second routine finalizes the capacity calculations. Another aspect of the invention ensures that the initialization routine can be repeated at a later time to re-compute appropriate bit and energy loadings to ensure that significant changes caused by line disturbances or large data rate variations can be quickly accommodated. In a preferred embodiment the resulting bit/energy loadings can be adjusted to be fully compliant with applicable Discrete Multi-Tone (DPM implementations of Asymmetric Digital Subscriber Loop (ADSL) protocols.

摘要翻译： 公开了一种在多信道数据传输信号中优化数据子信道的建立时间和比特和能量负载的控制的电路和方法。 超时时间或迭代计数用于控制设置时间。 初始化例程尝试在这样的超时期或迭代计数参数内进行适当的加载。 如果不能这样做，则进行第二个例程的切换以完成加载。 在优选实施例中，初始化例程计算粗略参数，而第二例程完成容量计算。 本发明的另一方面确保了可以在稍后时间重复初始化例程以重新计算适当的位和能量负载，以确保可以快速地适应由线路干扰或大数据速率变化引起的重大变化。 在优选实施例中，所得到的比特/能量负载可以被调整为完全符合可应用的离散多音（DPM实现的非对称数字用户环路（ADSL）协议）。