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公开(公告)号：EP0598346A3
公开(公告)日：1994-12-07
申请号：EP93118303.2
申请日：1993-11-11
发明人： Shen, Paul , Krause, Edward A. , Tom, Adam
摘要： A method and apparatus are provided for decoding variable length codewords carried in data blocks. A first buffer is loaded with a succession of data blocks. A second buffer is loaded with a first data block from the first buffer during a decoding cycle. The variable length codewords from the first data block in the second buffer are decoded to recover information. The process continues, with the second buffer being loaded with one data block at a time to successively decode new data blocks during successive decoding cycles.
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公开(公告)号：EP0615384A2
公开(公告)日：1994-09-14
申请号：EP94103640.2
申请日：1994-03-10
发明人： Wu, Allen , Krause, Edward A. , Paik, Woo H.
IPC分类号： H04N7/13
CPC分类号： H04N19/90 , H04N19/12 , H04N19/186 , H04N19/503 , H04N19/51 , H04N19/517 , H04N19/61
摘要： Digital video signals are adaptively compressed for communication to a receiver. Superblocks (230), each containing a plurality of blocks (232) of digital video data, are compressed using PCM, DPCM with a general motion vector for the entire superblock, and DPCM with a specific motion vector for each block contained within a superblock. The result of each compression mode is compared (58) after accounting for overhead data, to determine which results in the least amount of data for each block (232). These blocks are assembled into a superblock (230), and compared (80) together with necessary overhead and motion vector data to the same superblock processed using all PCM as well as the superblock processed using all DPCM. The comparison determines which compression mode produces the least amount of data for the superblock. The most compact superblock is selected for transmission. The transmitted superblocks are decoded by a decoder (Fig. 5) that recovers the necessary motion vectors and overhead information which identifies the type of compression used to provide the superblock.
摘要翻译： 数字视频信号被自适应地压缩以用于与接收机的通信。 使用具有用于整个超级块的通用运动矢量的PCM，DPCM以及包含在超级块内的每个块的特定运动矢量的DPCM对每个包含多个数字视频数据块（232）的超块（230）进行压缩。 在考虑开销数据之后，比较每个压缩模式的结果（58），以确定每个块的最小数据量（232）的结果。 这些块被组装成超级块（230），并且将必要的开销和运动矢量数据与使用所有PCM处理的相同超级块以及使用所有DPCM处理的超级块进行比较（80）。 比较确定哪个压缩模式为超级块产生最少量的数据。 选择最紧凑的超级块进行传输。 传输的超级块由解码器（图5）解码，该解码器恢复必要的运动矢量和开销信息，其识别用于提供超级块的压缩类型。
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公开(公告)号：EP0579075A3
公开(公告)日：1994-08-31
申请号：EP93110691.8
申请日：1993-07-05
发明人： Moroney, Paul , Grover, Glen A.
IPC分类号： H04N7/13
CPC分类号： H04N21/434 , H04N7/54 , H04N19/61 , H04N19/89 , H04N21/236
摘要： A succession of variable length data packets containing a header portion and data portion are received. Selected data from the data packet headers is stored in designated locations of a header memory. A data packet start address is provided with each stored header portion to designate a location in a data memory for commencing the storage of data contained in a corresponding data packet. The data from the received data packets is stored commencing in the data memory locations designated by the corresponding data packet start addresses. In an illustrated embodiment, the data packets are macroblocks from digitized television frames. A plurality of next data packet position indicators are provided in the data, for use in periodically verifying macroblock boundaries during the receipt of the television data and to provide a rapid recovery from a transmission error affecting the actual or identified length of a macroblock.
摘要翻译： 接收包含报头部分和数据部分的一系列可变长度数据分组。 从数据分组头中选择的数据存储在头部存储器的指定位置。 数据分组起始地址与每个存储的报头部分一起提供，以指定数据存储器中的位置，用于开始存储包含在相应数据分组中的数据。 来自接收的数据分组的数据被存储在由对应的数据分组起始地址所指定的数据存储器位置中。 在所示实施例中，数据分组是来自数字化电视帧的宏块。 在数据中提供多个下一个数据分组位置指示符，用于在接收电视数据期间周期性地验证宏块边界，并提供从影响宏块实际或识别长度的传输错误中的快速恢复。
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84.发明公开
公开(公告)号：EP0562419A3
公开(公告)日：1994-06-22
申请号：EP93104282.4
申请日：1993-03-16
摘要： Apparatus (10) is provided for decoding variable length code words to recover transform coefficients, such as DCT transform coefficients provided by a high definition television encoder. A first category of the code words has a length of no more than n bits. A second category has a length of greater than n bits. A feedback ROM (22) is used to decode the code words. Code words from the first category are processed by directly addressing a lookup table (80) in the ROM (22). Code words from the second category are processed using multiple passes through the ROM (22), wherein a portion of the data output during a prior pass is fed back (90) to address the memory during a subsequent pass.
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85.发明公开Spontaneous emission source having high spectral density at a desired wavelength 失效Quellefürspontane Emission mit hoher spektraler Dichte bei einergewünschterWellenlänge。
公开(公告)号：EP0597436A1
公开(公告)日：1994-05-18
申请号：EP93118110.1
申请日：1993-11-09
发明人： Huber, David R.
CPC分类号： H04B10/2507 , H01S3/0085 , H01S3/0604 , H01S3/0627 , H01S3/063 , H01S3/06795 , H01S3/094003 , H01S3/10092 , H01S5/0085 , H01S5/0608 , H01S5/06213 , H01S5/0652 , H01S5/4006 , H01S5/50 , H01S2301/03 , H04B10/2537
摘要： A spontaneous emission source has a high spectral density at a desired wavelength. An integrated guided wave optical path is formed in either a semiconductor or silica substrate. An active medium and grating are provided within the optical path. The optical path is pumped to pass energy across the grating and active medium. The pump energy excites the active medium without lasing to output spontaneous emissions at a wavelength established by the grating. The source is particularly useful for reducing nonlinear effects in an optical fiber used for communicating AM or other information signals.
摘要翻译： 自发发射源在所需波长处具有高光谱密度。 在半导体或二氧化硅衬底中形成集成的导波光路。 在光路内提供有源介质和光栅。 泵浦光路以通过光栅和活性介质的能量。 泵浦能量激发有源介质而不激光以在由光栅建立的波长处输出自发辐射。 该源对于减少用于传送AM或其他信息信号的光纤中的非线性效应特别有用。
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86.发明公开Optical fiber amplifier and laser with flattened gain slope 失效FaseroptischeVerstärkerund Laser mitgleichmässigemGewinnspektrum。
公开(公告)号：EP0582860A1
公开(公告)日：1994-02-16
申请号：EP93111580.2
申请日：1993-07-20
发明人： Huber, David R.
IPC分类号： H01S3/06
CPC分类号： H01S3/067 , H01S3/0675 , H01S3/06754 , H01S2301/04
摘要： An in-fiber Bragg grating is used to flatten the gain slope of a fiber optical amplifier or optical fiber laser. The grating can be formed using photorefractive techniques, and is placed within a guided wave portion of a doped optical fiber. The grating is oriented at a nonperpendicular angle with respect to a longitudinal axis of the fiber, and has an interaction wavelength that is selected to flatten the gain slope of the device by diverting excess spontaneous emission therefrom. The interaction wavelength is preferably selected to correspond to a wavelength at or near that at which the spontaneous emission produced by the fiber peaks.
摘要翻译： 光纤布拉格光栅用于平坦化光纤放大器或光纤激光器的增益斜率。 光栅可以使用光折射技术形成，并且被放置在掺杂光纤的导波部分内。 光栅相对于光纤的纵向轴线以非垂直角定向，并且具有相互作用波长，该相互作用波长被选择以通过转移其过量的自发发射来平坦化器件的增益斜率。 优选选择相互作用波长以对应于由纤维峰产生的自发发射的波长处或附近的波长。
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公开(公告)号：EP0531028A3
公开(公告)日：1993-11-10
申请号：EP92307668.1
申请日：1992-08-21
发明人： Lee, Chong U. , Krause, Edward A. , Shen, Paul X.
摘要： In a broadcast communication system, a plurality of transmitters (T₁, T₂, ... T M ) are located at different locations throughout a broadcast area for separately and synchronously broadcasting a common digital communication signal at a predetermined frequency over different signal paths, and a receiver (10, 12) located within the broadcast area receives the common digital communication signal separately broadcast by a plurality of the transmitters at the predetermined frequency over different signal paths and processes the received signal to reproduce the common digital communication signal without the effects of multipath and other channel distortions. The received signal is modified in relation to the broadcast signal by channel responses of the different signal paths; and the receiver includes an adaptive equalization filter (12) for processing the received signal inversely in accordance with a collection of the channel responses of the different signal paths to reproduce the common digital communication signal without the effects of multipath and other channel distortions. The accuracy of the filter in processing the received signal in accordance with the inverse of the collection of the channel responses of the different signal paths is enhanced by adapting the filter to reproduce a predetermined known common digital communication signal without the effects of multipath and other channel distortions.
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88.发明公开Variable length code word decoder for use in digital communication systems 失效存储器中，用于在数字通信系统中用于解码可变长度字和解码器和方法
公开(公告)号：EP0562419A2
公开(公告)日：1993-09-29
申请号：EP93104282.4
申请日：1993-03-16
摘要： Apparatus (10) is provided for decoding variable length code words to recover transform coefficients, such as DCT transform coefficients provided by a high definition television encoder. A first category of the code words has a length of no more than n bits. A second category has a length of greater than n bits. A feedback ROM (22) is used to decode the code words. Code words from the first category are processed by directly addressing a lookup table (80) in the ROM (22). Code words from the second category are processed using multiple passes through the ROM (22), wherein a portion of the data output during a prior pass is fed back (90) to address the memory during a subsequent pass.
摘要翻译： 装置（10）被设置用于解码可变长度码字以恢复的变换系数：如DCT变换由高清晰度电视编码器提供系数。 码字的第一类具有不超过n位的长度。 第二类具有大于n位的长度。 反馈ROM（22）用于将码字进行解码。 从第一类的码字是通过在ROM（22）直接寻址的查找表（80）进行处理。 从第二类代码字是通过ROM（22），使用多遍处理，现有右期间worin所述数据输出的一部分被反馈（90）到随后的通过期间寻址存储器。
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公开(公告)号：EP0524559A3
公开(公告)日：1993-05-19
申请号：EP92112305.5
申请日：1992-07-18
发明人： Paik, Woo H. , Lery, Scott A. , Tom, Adam S.
CPC分类号： H04L25/0314 , H04L27/3827
摘要： A method and apparatus are provided for adaptively equalizing data signals in a communications receiver. An unequalized data signal is demodulated. The demodulated data signal is filtered in an adaptive equalizer (60) that initially updates adaptive filter coefficients using error signals derived from a first algorithm. A carrier lock signal is generated (62, 78) when a phase error of a filtered signal output from the adaptive equalizer reaches a threshold value. The adaptive filter coefficients are updated (74) using error signals derived from a second algorithm instead of the first algorithm in response to the carrier lock signal (72). The first algorithm is a self-recovering equalization algorithm such as the Constant Modulus Algorithm. The second algorithm can be a decision directed algorithm. Carrier phase is recovered without the use of a phase rotator or phase de-rotator, by locating the adaptive equalizer inside of the carrier recovery loop (56). The invention is particularly adapted for use in the recovery of multilevel amplitude modulated data, such as QAM data.
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公开(公告)号：EP0467040A3
公开(公告)日：1993-03-24
申请号：EP91108087.7
申请日：1991-05-18
发明人： Krause, Edward A. , Paik, Woo H. , Liu, Vincent , Esserman, Jim
IPC分类号： H04N7/137
CPC分类号： H04N19/107 , H04N19/51 , H04N19/61
摘要： A method and apparatus are provided for processing digital video signals for transmission in a compressed form. A set of pixel data is compressed without motion compensation to provide a first compressed video signal. The pixel data is compressed using motion compensation to provide a second compressed video signal. The data in the first and second compressed video signals is quantified. A comparison is made to determine which of the signals contains the least data. Successive sets of pixel data are sequentially compressed and quantified and the compressed video signal having the least data for each particular set is selected. The selected signals are encoded to identify them as motion compensated or non-motion compensated signals, and combined to provide a compressed video signal data stream for transmission. Apparatus for receiving and decoding the signals is also disclosed.
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