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公开(公告)号：EP0525641A3
公开(公告)日：1993-08-04
申请号：EP92112587.8
申请日：1992-07-23
发明人： Paik, Woo H. , Lery, Scott A. , Heegard, Chris
CPC分类号： H04L1/0057 , H04L1/006 , H04L1/0065 , H04L1/0071 , H04L27/3438 , H04N7/015 , H04N21/2383 , H04N21/4382
摘要： Coded modulation schemes based on codes for QPSK modulation are directly incorporated into QAM based modulation systems, forming trellis coded QAM, to provide a practical coding structure that is both efficient in bandwidth and data reliability. Concatenated coding with QPSK based trellis coding and symbol error correcting coding is used. In an encoder (Fig. 2), an N-bit QAM constellation pattern (80) is divided into four subsets, each including N/4 symbol points of the constellation pattern. A two-bit QPSK codeword (92) is assigned to each of the four subsets (82, 84, 86, 88). A symbol to be transmitted is first encoded using an outer error correcting encoding algorithm, such as a Reed-Solomon code (12). Part of the symbol is then encoded (48) with an inner code that comprises a rate 1/2 trellis encoding algorithm to provide a QPSK codeword, which is mapped (50) with the remaining bits of the symbol to provide a modulation function, wherein the remaining bits (94) correlate the symbol with one of the symbol points included in the subset defined by the QPSK codeword. At a receiver (Fig. 3), the recovered modulation function is pruned (62) to provide a set of metrics (66) corresponding to the subsets and to provide a plurality of conditional determinations of the constellation point identified by the remaining bits. The metrics are used in a rate 1/2 trellis decoder (68) to recover a first bit that is encoded using a rate 1/2 encoding algorithm to recreate the QPSK codeword. One of a plurality of the conditional determinations is selected in response to the recreated codeword. The selected conditional determination is combined with the recovered first bit to provide a decoded output that is further decoded using a symbol error correcting algorithm such as a Reed-Solomon code (36).
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142.发明公开Statistical multiplexer for a multichannel image compression system 失效Statistischer Multiplexerfürein Multikanal-Bildkomprimierungssystem。
公开(公告)号：EP0550843A1
公开(公告)日：1993-07-14
申请号：EP92121030.8
申请日：1992-12-10
CPC分类号： H04N21/2365 , H04N19/115 , H04N19/124 , H04N19/15 , H04N19/152 , H04N19/176 , H04N19/30 , H04N21/23655 , H04N21/4347
摘要： A multichannel image compression system uses a plurality of encoders (10, 12 ... 14) to compress image data. A coding level command is provided to each of the encoders to specify a level of quality to be provided by each encoder. Encoded image data, provided by the encoders in response to the coding level command, is multiplexed (26) into a combined signal for transmission. The coding level command is adjusted in response to an accumulated amount of data from the combined signal, to maintain the accumulated data within a throughput capability of a communication channel (48). Although the coding level command may specify a global coding level that is the same for all of the encoders, the encoders can derive local coding levels from the global coding level to provide different encoding qualities. Decoder apparatus (30-46) is provided to recover an image from the compressed image data.
摘要翻译： 多通道图像压缩系统使用多个编码器（10,12〜14）来压缩图像数据。 为每个编码器提供编码电平命令，以指定由每个编码器提供的质量水平。 由编码器响应于编码电平命令提供的编码图像数据被多路复用（26）成为用于发送的组合信号。 响应于来自组合信号的累积的数据量来调整编码电平命令，以将累积的数据保持在通信信道（48）的吞吐量能力内。 虽然编码电平命令可以指定对于所有编码器相同的全局编码电平，编码器可以从全局编码级别导出本地编码电平，以提供不同的编码质量。 提供解码器装置（30-46）以从压缩图像数据中恢复图像。
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143.发明公开Conversion of television signal formats with retention of common control data stream 失效电视信号格式转换与保留共同控制数据流
公开(公告)号：EP0512398A3
公开(公告)日：1993-06-16
申请号：EP92107326.8
申请日：1992-04-29
摘要： Television signals are converted from a first format to a plurality of different formats while retaining a common control data stream. A first television signal in a first format is separated into a first signal portion (12, 14) carrying television information and a second signal portion (12, 16) carrying control data. The first signal portion is reformatted into a second format (22). The second signal portion is combined with the reformatted first signal portion to provide a second television signal (22, 28, 32). In this manner, a plurality of television signals having different formats can be transmitted with common control data, e.g., for controlling access to television programming.
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144.发明公开Method and apparatus for enhancing the security of a scrambled television signal 失效用于增强屏蔽电视信号安全性的方法和装置
公开(公告)号：EP0518129A3
公开(公告)日：1993-05-19
申请号：EP92108925.6
申请日：1992-05-27
IPC分类号： H04N7/167
CPC分类号： H04N7/1693
摘要： The scrambling security of a sync suppressed television signal is enhanced by eliminating the fixed time relationship between the normal color burst component and synchronization information in successive lines of the television signal. Transmission of a first plurality of television lines is delayed to achieve a cumulative delay corresponding at least to the duration of a color burst component of the television signal. The transmission of a second plurality of television lines is subsequently accelerated to reduce the cumulative delay. By repeating the delaying and accelerating steps, the location of the color burst component is varied within the television signal over time. Derivation of a substitute horizontal synchronization pulse from the color burst component is thereby prevented.
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145.发明公开Method and apparatus for communicating compressed digital video signals using multiple processors 失效使用多个处理器传播压缩数字视频信号的方法和装置
公开(公告)号：EP0499088A3
公开(公告)日：1993-05-19
申请号：EP92101401.5
申请日：1992-01-29
发明人： Shen, Paul , Krause, Edward A. , Paik, Woo H.
CPC分类号： H04N19/00 , H04N19/107 , H04N19/30 , H04N19/436 , H04N19/577 , H04N19/61 , H04N19/70 , H04N21/236 , H04N21/434
摘要： Digital video signals are processed by a plurality of independently operating processors (42, 44, 46, 48) to provide data for transmission in a compressed, motion compensated form. A video image frame area (10) is divided into a set of subframes (12, 16, 20, 24). The set of subframes is systematically shifted such that the individual subframes progressively cycle across and wrap around the video image frame area. For each successive video frame, video image data bounded by each of the different subframes is independently compressed using motion estimation to reduce data redundancy among the successive frames. The motion estimation is limited for each subframe of a current video frame to areas of a previous video frame that were bounded by the same subframe in the previous frame. In an illustrated embodiment, the set of subframes (12, 16, 20, 24) is shifted once for each successive video frame, and each subframe includes a refresh region (14, 18, 22, 26) whereby the video image frame area (10) is progressively refreshed as the subframes are shifted thereacross. Receiver apparatus (60-82) for use in decoding the independently processed subframe data is also disclosed.
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公开(公告)号：EP0523484A3
公开(公告)日：1993-05-05
申请号：EP92111366.8
申请日：1992-07-03
发明人： Huber, David R.
CPC分类号： H04B10/2912 , H01S3/0675 , H01S3/06795 , H01S3/08086 , H01S3/094023 , H04B10/291 , H04B10/506 , H04B2210/003
摘要： A narrow bandwidth incoherent optical source is provided. A superluminescent source includes a gain medium having an input end and an output end. The input end of the gain medium is optically coupled to a reflector to cause spontaneous emissions within a predetermined band exiting the input of the gain medium to be reflected back into the medium. Spontaneous emissions outside of the predetermined band are lost. The gain medium can comprise a doped fiber, such as an Erbium doped fiber. An optical isolator prevents the superluminescent source from lasing. By providing a plurality of reflectors operating in different bands, the superluminescent source can generate a plurality of optical carriers.
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147.发明公开Low distortion laser system for am fiber optic communication 失效Verzerrungsarmes LasersystemfürAM faseroptischeÜbertragung。
公开(公告)号：EP0528225A2
公开(公告)日：1993-02-24
申请号：EP92112971.4
申请日：1992-07-30
发明人： Glaab, Joseph B. , Huber, David R.
IPC分类号： H04B10/18
CPC分类号： H04B10/2507
摘要： An information signal modulates a first optical carrier. The information signal is inverted to modulate a second optical carrier. The modulated first and second optical carriers are multiplexed into a single optical signal for communication over an optical fiber path. At a receiver, the optical signal is demultiplexed to recover the information signal and the inverted information signal. The recovered signals are combined to provide the information signal in the electrical domain with reduced distortion. A dual-detector balanced optical diode pair can be used to combine the recovered information and inverted information signals and provide an analog RF output. The apparatus is particularly suitable for the transmission of AM-VSB television signals.
摘要翻译： 信息信号调制第一光载波。 信息信号被反相以调制第二光学载体。 经调制的第一和第二光载波被复用到单个光信号中，用于通过光纤路径进行通信。 在接收机处，光信号被解复用以恢复信息信号和反相信息信号。 恢复的信号被组合以在电域中提供具有减小的失真的信息信号。 双检测器平衡光二极管对可用于组合恢复的信息和反相信息信号，并提供模拟RF输出。 该装置特别适用于AM-VSB电视信号的传输。
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148.发明公开
公开(公告)号：EP0525641A2
公开(公告)日：1993-02-03
申请号：EP92112587.8
申请日：1992-07-23
发明人： Paik, Woo H. , Lery, Scott A. , Heegard, Chris
CPC分类号： H04L1/0057 , H04L1/006 , H04L1/0065 , H04L1/0071 , H04L27/3438 , H04N7/015 , H04N21/2383 , H04N21/4382
摘要： Coded modulation schemes based on codes for QPSK modulation are directly incorporated into QAM based modulation systems, forming trellis coded QAM, to provide a practical coding structure that is both efficient in bandwidth and data reliability. Concatenated coding with QPSK based trellis coding and symbol error correcting coding is used. In an encoder (Fig. 2), an N-bit QAM constellation pattern (80) is divided into four subsets, each including N/4 symbol points of the constellation pattern. A two-bit QPSK codeword (92) is assigned to each of the four subsets (82, 84, 86, 88). A symbol to be transmitted is first encoded using an outer error correcting encoding algorithm, such as a Reed-Solomon code (12). Part of the symbol is then encoded (48) with an inner code that comprises a rate 1/2 trellis encoding algorithm to provide a QPSK codeword, which is mapped (50) with the remaining bits of the symbol to provide a modulation function, wherein the remaining bits (94) correlate the symbol with one of the symbol points included in the subset defined by the QPSK codeword. At a receiver (Fig. 3), the recovered modulation function is pruned (62) to provide a set of metrics (66) corresponding to the subsets and to provide a plurality of conditional determinations of the constellation point identified by the remaining bits. The metrics are used in a rate 1/2 trellis decoder (68) to recover a first bit that is encoded using a rate 1/2 encoding algorithm to recreate the QPSK codeword. One of a plurality of the conditional determinations is selected in response to the recreated codeword. The selected conditional determination is combined with the recovered first bit to provide a decoded output that is further decoded using a symbol error correcting algorithm such as a Reed-Solomon code (36).
摘要翻译： 基于用于QPSK调制的编码的编码调制方案直接并入基于QAM的调制系统中，形成网格编码QAM，以提供在带宽和数据可靠性方面都有效的实用编码结构。 使用基于QPSK的网格编码和符号纠错编码的并行编码。 在编码器（图2）中，N位QAM星座图（80）被划分成四个子集，每个子集包括星座图案的N / 4个符号点。 将两比特QPSK码字（92）分配给四个子集（82,84,86,88）中的每一个。 首先使用诸如Reed-Solomon码（12）之类的外部纠错编码算法对要发送的符号进行编码。 然后使用包含速率1/2格状编码算法的内码对部分符号（48）进行编码（48），以提供与所述符号的剩余比特（50）映射（50）以提供调制功能的QPSK码字，其中 其余位（94）使符号与包括在由QPSK码字定义的子集中的符号点之一相关联。 在接收机（图3），修复恢复的调制功能（62）以提供对应于子集的一组度量（66），并提供由剩余比特识别的星座点的多个条件确定。 度量用于速率1/2网格解码器（68）以恢复使用速率1/2编码算法编码的第一比特，以重新创建QPSK码字。 响应于重新创建的码字来选择多个条件确定中的一个。 选择的条件确定与恢复的第一位组合以提供使用诸如里德 - 所罗门码（36）的符号纠错算法进一步解码的解码输出。
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公开(公告)号：EP0523484A2
公开(公告)日：1993-01-20
申请号：EP92111366.8
申请日：1992-07-03
发明人： Huber, David R.
CPC分类号： H04B10/2912 , H01S3/0675 , H01S3/06795 , H01S3/08086 , H01S3/094023 , H04B10/291 , H04B10/506 , H04B2210/003
摘要： A narrow bandwidth incoherent optical source is provided. A superluminescent source includes a gain medium having an input end and an output end. The input end of the gain medium is optically coupled to a reflector to cause spontaneous emissions within a predetermined band exiting the input of the gain medium to be reflected back into the medium. Spontaneous emissions outside of the predetermined band are lost. The gain medium can comprise a doped fiber, such as an Erbium doped fiber. An optical isolator prevents the superluminescent source from lasing. By providing a plurality of reflectors operating in different bands, the superluminescent source can generate a plurality of optical carriers.
摘要翻译： 提供窄带宽非相干光源。 超发光源包括具有输入端和输出端的增益介质。 增益介质的输入端光耦合到反射器，以引起从增益介质的输入端出射的预定频带内的自发发射被反射回到介质中。 预定频段之外的自发辐射会丢失。 增益介质可以包括掺杂光纤，例如铒掺杂光纤。 光学隔离器可防止超发光源发出激光。 通过提供在不同频带中操作的多个反射器，超发光源可以生成多个光载波。
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150.发明公开Prevention of inspection of secret data stored in encapsulated integrated circuit chip 失效防止在封装集成电路芯片中存储的秘密数据的检查
公开(公告)号：EP0479461A3
公开(公告)日：1992-12-30
申请号：EP91308623.7
申请日：1991-09-23
CPC分类号： H01L23/576 , G06F21/87 , G06F2221/2143 , G11C7/24 , G11C8/20 , G11C16/22 , H01L2924/0002 , Y10S257/922 , H01L2924/00
摘要： An integrated circuit chip includes a secure memory element (10) that stores secret data, an opaque layer of material (14) encapsulating the chip, and means (12) for eliminating the secret data from the secure memory element in the event that the encapsulation material is removed from the chip. The eliminating means comprise a protective circuit encapsulated by the encapsulation material and coupled to the secure memory element. The protective circuit includes a light sensitive element (42, 90, 110, 122) having a current characteristic that has a detectable change upon exposure to light; means (16, 16a, 16b, 16c) for detecting said current change when the light sensitive element is exposed to light; and switching means (18) coupled to the secure memory element and the detecting means for causing the secret data to be removed from the secure memory element in response to said current change produced by the light sensitive element when the light sensitive element is exposed to light, such that should the encapsulation material be removed from the chip, the secret data is eliminated from the memory element.
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