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51. 发明公开

EP1173932A4 APPARATUS AND METHOD FOR NORMALIZING METRIC VALUES IN A COMPONENT DECODER IN A MOBILE COMMUNICATION SYSTEM 审中-公开
标题翻译：设备和方法，解码器组件度量值在移动通信系统正常化
公开(公告)号：EP1173932A4
公开(公告)日：2007-05-09
申请号：EP00925707
申请日：2000-04-27
申请人： SAMSUNG ELECTRONICS CO LTD
发明人： LEE YOUNG-HWAN , KIM MIN-GOO , KIM BEONG-JO
IPC分类号： H03M13/41 , H03M13/01 , H03M13/23 , H04B7/26 , H04L1/00 , H04L25/03 , H04Q7/38
CPC分类号： H04L25/03197 , H03M13/4107 , H03M13/6583
摘要： Disclosed is a method for normalizing metric values in a decoder which uses a plurality of metric values of a next state in a state transition period having a present state and the next state, each metric value having a survival path metric value having a value equal to or higher than a competition path metric value. The method comprises detecting the survival path metric values out of the metric values; detecting a minimum survival path metric value out of the detected survival path metric values; determining whether the detected minimum survival path metric value exceeds a threshold value; and subtracting, when the minimum survival path metric value exceeds the threshold value, a given normalization value from the metric values, to output normalized metric values. Another disclosed is a method for normalizing metric values in a decoder which uses a plurality of metric values of a next state in a state transition period having a present state and the next state, each metric value having a survival path metric value having a value equal to or higher than a competition path metric value. The method comprises detecting the competition path metric values out of the metric values; detecting a minimum competition path metric value out of the detected competition path metric values; determining whether the detected minimum competition path metric value is greater than a threshold value; and subtracting, when the minimum competition path metric value is greater than the threshold value, a given normalization value to output normalized metric values.

52. 发明公开

EP1622277A1 Enhanced Viterbi equalizer and algorithm 审中-公开
标题翻译： Verbesserter Viterbi Entzerrer und Verfahren
公开(公告)号：EP1622277A1
公开(公告)日：2006-02-01
申请号：EP05291511.3
申请日：2005-07-12
申请人： ALCATEL
发明人： Buchali, Fred , Bülow, Henning
IPC分类号： H03M13/41
CPC分类号： H04L25/03254 , H04L25/03197
摘要： A device (1) for receiving a distorted signal, in particular an optical signal converted by an opto/electrical converter (2), comprises an electrical low-pass filter (3), an analog/digital converter (4), and a Viterbi equalizer (5). The bandwidth of the electrical low-pass filter (3) and the sampling rate of the device (1) are set such that a noise sample at an actual sampling time is correlated to one or more noise samples at one or more adjacent sampling times and the Viterbi equalizer (5) comprises a means (5a) for mitigating inter-symbol interference by taking into account correlation of the different noise samples at the actual sampling time and one or more adjacent sampling times.
摘要翻译：用于接收失真信号的设备（1），特别是由光/电转换器（2）转换的光信号，包括电低通滤波器（3），模拟/数字转换器（4）和维特比均衡器（5）。电气低通滤波器（3）的带宽和设备（1）的采样率被设置为使得实际采样时间的噪声样本与一个或多个相邻采样时间的一个或多个噪声样本相关，并且维特比均衡器（5）包括用于通过考虑实际采样时间和一个或多个相邻采样时间的不同噪声样本的相关性来减轻符号间干扰的装置（5a）。

53. 发明公开

EP1555784A1 Method and apparatus for optimizing tree pruning in a multiuser detector 失效转让
标题翻译：用于树修剪的在多用检测器的最优化的方法和装置
公开(公告)号：EP1555784A1
公开(公告)日：2005-07-20
申请号：EP04075124.0
申请日：2004-01-19
申请人： BAE SYSTEMS Information and Electronic Systems Integration, Inc.
发明人： Learned Rachel E., Bae Systems Info.&Elec.Sys.Int.
IPC分类号： H04L25/03 , H04L25/08
CPC分类号： H04L25/03171 , H03M13/3955 , H04B1/7105 , H04L25/0204 , H04L25/03197 , H04L25/03229 , H04L25/03331 , H04W16/14
摘要： A multi-user decoder is disclosed in which interfering users are assigned to levels of a decoding tree constructed in the decoder dependent on the power levels of the user's received signals and for each symbol interval. By building the decoding tree in this manner for each symbol interval, a reduced complexity search is more likely to include paths and nodes in the tree containing the correct value for the channel symbols.

54. 发明授权

EP1075752B1 TRANSMITTER/RECEIVER FOR GMSK AND OFFSET-QAM 有权
标题翻译：发射机/接收机，GMSK和偏移QAM
公开(公告)号：EP1075752B1
公开(公告)日：2005-06-22
申请号：EP99918454.2
申请日：1999-04-27
申请人： Ericsson Inc.
发明人： DENT, Paul, W.
IPC分类号： H04L27/36 , H04L27/20 , H04L27/00 , H04L25/03
CPC分类号： H04L27/362 , H04L1/0054 , H04L25/0226 , H04L25/03197 , H04L25/03292 , H04L27/0008 , H04L27/2017 , H04L27/3488

55. 发明公开

EP1494413A1 Channel estimation and sequence estimation for the reception of optical signal 审中-公开
标题翻译：信道和序列估计用于接收光信号
公开(公告)号：EP1494413A1
公开(公告)日：2005-01-05
申请号：EP03015024.7
申请日：2003-07-02
申请人： CoreOptics, Inc., c/o The Corporation Trust Center
发明人： Langenbach, Stefan , Stojanovic, Nebojsa, Prof. Dr.
IPC分类号： H04L25/03
CPC分类号： H04L25/03197 , H04L7/0004 , H04L7/007
摘要： The application relates to channel estimation. The method comprises digitizing an analogue signal thereby associating one digital word with the level of said analogue signal at each sampling time. The most likely sequence of symbols is detected. To this end branch metrics are calculated. According to one embodiment, a symbol period comprises at least two sampling times. Moreover the branch metrics are obtained from frequencies of digital words resulting from a digitizing and the symbols of the most likely sequence. According to another embodiment a symbol period comprises at least one sampling time. Events are counted wherein each event is defined by a channel state and a current digital word. Each channel state is defined by a pattern of symbols relative to a current symbol determined at the time of a current digital word. A model distribution is fitted to event counts and branch metrics is obtained from the fitted model distribution. Moreover the invention relates to corresponding symbol detectors for optical receivers.

56. 发明公开

EP1111863A3 Method and apparatus for shortening the critical path of reduced complexity sequence estimation techniques 有权
标题翻译：用于序列估计方法中的关键路径的缩短的方法和装置减少Kompexität
公开(公告)号：EP1111863A3
公开(公告)日：2004-04-14
申请号：EP00310939.4
申请日：2000-12-08
申请人： LUCENT TECHNOLOGIES INC.
发明人： Azadet, Kameran , Haratsch, Erich Franz
IPC分类号： H04L25/03 , H04L27/34
CPC分类号： H04L25/03197 , H04L25/03235 , H04L25/03299
摘要： A method and apparatus are disclosed for improving the processing time of reduced complexity sequence estimation techniques, such as reduced state sequence estimation (RSSE). The possible values for the branch metrics in the RSSE are precomputed to permit pipelining and the shortening of the critical path. Precomputing the branch metrics for all possible symbol combinations in the channel memory makes it possible to remove the branch metrics unit (BMU) and decision-feedback unit (DFU) from the feedback loop, thereby reducing the critical path. A look-ahead branch metrics unit (LABMU) and an intersymbol interference canceller (ISIC) precompute the branch metrics for all possible values for the channel memory. At the beginning of each decoding cycle, a set of multiplexers (MUXs) select the appropriate branch metrics based on the survivor symbols in the corresponding survivor path cells (SPCs), which are then sent to an add-compare-select unit (ACSU). The computational load of the precomputations is reduced for multi-dimensional trellis codes by precomputing each dimension of the multi-dimensional trellis code separately. Prefiltering techniques are used to reduce the computational complexity by shortening the channel memory. A hybrid survivor memory architecture is also disclosed for a RSSE for a channel having a channel memory of length L, where the survivors corresponding to the L past decoding cycles are stored in a register exchange architecture (REA), and survivors corresponding to later decoding cycles are stored in a trace-back architecture (TBA) or register exchange architecture (REA). Symbols are mapped to information bits to reduce the word size before being moved from the first register exchange architecture (REA) to the trace-back architecture (TBA) or the second register exchange architecture (REA).

57. 发明公开

EP1256217A1 METHODS, RECEIVERS AND EQUALIZERS HAVING INCREASED COMPUTATIONAL EFFICIENCY 有权
标题翻译： VERFHAREN，接收器和均衡，以更高的效率计算
公开(公告)号：EP1256217A1
公开(公告)日：2002-11-13
申请号：EP01904890.9
申请日：2001-01-17
申请人： Ericsson Inc.
发明人： ZANGI, Kambiz, C. , RAMESH, Rajaram , HUI, Dennis , CHENG, Jung-Fu
IPC分类号： H04L25/03
CPC分类号： H04L25/03197 , H04L25/03235 , H04L2025/03401
摘要： Metrics associated with each branch from a previous hypothesized trellis state to each respective possible current trellis state in a DFSE equalizer can be calculated. In particular, a common portion of branch metrics can be calculated that is common to each of the branch metrics from the previous hypothesized state to each of the current possible states, and difference variables representing a difference between the common portion of the branch metrics and each of the branch metrics from the previous hypothesized state to each of the current possible states can also be calculated. The common portion of the branch metric and each of the difference variables can then be combined to provide a respective metric for each of the possible current states.

58. 发明公开

EP1211857A1 Procédé et dispositif d'estimation des valeurs successives de symboles numériques, en particulier pour l'égalisation d'un canal de transmission d'informations en téléphonie mobile 审中-公开
标题翻译：在移动电话估计用于数据传输信道的均衡特别是数字符号的连续值的方法和装置
公开(公告)号：EP1211857A1
公开(公告)日：2002-06-05
申请号：EP00125395.4
申请日：2000-12-04
申请人： STMicroelectronics N.V.
发明人： Chappaz, David
IPC分类号： H04L25/03
CPC分类号： H04L25/03197 , H04L25/03191
摘要： On estime les valeurs successives des symboles numériques pouvant prendre chacun M valeurs possibles différentes, à partir des valeurs successives d'échantillons numériques dont chacun résulte de la combinaison d'au plus L symboles successifs. Cette estimation comporte une progression étage par étage dans un treillis du type Viterbi à M k états, avec k inférieur ou égal à L-1, tous les états de tous les étages étant respectivement affectés de métriques cumulées. A la prise en compte de l'échantillon de rang n, on partitionne en M groupes toutes les transitions parvenant aux différents états de l'étage courant du treillis, chaque groupe contenant toutes les transitions issues des états de l'étage précédent associés à l'une des M valeurs possibles du symbole de rang n-k, on calcule pour ces différents états de l'étage courant du treillis les différentes métriques cumulées, on détermine dans chaque groupe celle des transitions qui conduit à l'état affecté d'une métrique cumulée extremale, et on prend une décision unique sur la valeur du symbole de rang n-k en détectant le groupe associé à l'extremum de ces M métriques cumulées extremales , cette décision unique étant affectée d'un indice de confiance-symbole élaboré à partir de ces M métriques cumulées extremales.
摘要翻译：估计使用维特比和累计度量。 n个样本取（80）以及形成生产过渡M基团。所有的转换属于格的不同状态。从过渡团，从而导致这些外部累积度量的（83）中找到，以及最小累积度量（82）。上的符号值（86），则判定从两个度量集找到。

59. 发明公开

EP1106004A1 LOW COMPLEXITY DECISION FEEDBACK SEQUENCE ESTIMATION 有权
标题翻译：决定BACK综合影响估计低复杂度
公开(公告)号：EP1106004A1
公开(公告)日：2001-06-13
申请号：EP99943586.0
申请日：1999-08-17
申请人： TELEFONAKTIEBOLAGET L M ERICSSON (publ)
发明人： JÄVERBRING, Stefan
IPC分类号： H04L25/03 , H03M13/00
CPC分类号： H03M13/6331 , H03M13/39 , H03M13/41 , H03M13/6502 , H03M13/6505 , H04L25/03197 , H04L25/03235
摘要： A Decision Feedback Sequence Estimator (DFSE) metric is determined by storing one or more tables of Decision Feedback Estimation (DFE) hypotheses in a memory, and then using values of the DFE hypotheses that are retrieved from storage to determine the DFSE metric. The DFE hypotheses may be precalculated (509) and stored into the memory (511) prior to performance of any retrieval operation. Alternatively, the table may start out empty, and the DFE hypotheses may be determined as needed for a particular DFSE metric computation. The determined DFE metric may then be stored into a table for later retrieval if the metric is needed again. The DFE hypotheses may be stored into a single table or, to reduce memory requirements and computational complexity, may be stored into corresponding ones of plural tables. MLSE hypotheses, which are also used in the DFSE metric determination, may similarly be stored into one or more tables (503, 505) for later retrieval as needed.

60. 发明公开

EP1075752A2 TRANSMITTER/RECEIVER FOR GMSK AND OFFSET-QAM 有权
标题翻译：发射机/接收机，GMSK和偏移QAM
公开(公告)号：EP1075752A2
公开(公告)日：2001-02-14
申请号：EP99918454.2
申请日：1999-04-27
申请人： ERICSSON INC.
发明人： DENT, Paul, W.
IPC分类号： H04L27/36 , H04L27/20 , H04L27/00 , H04L25/03
CPC分类号： H04L27/362 , H04L1/0054 , H04L25/0226 , H04L25/03197 , H04L25/03292 , H04L27/0008 , H04L27/2017 , H04L27/3488
摘要： A transmitter encodes a number 2N data bits by using N data bits to select one of 2N levels of a cosine wave and the other N data bits to select one of 2N levels of a sine wave. The modulation attains the cosine wave levels at instants offset by half an N-bit symbol interval with respect to the sine wave levels, and is called Offset QAM (OQAM). A received OQAM signal is amplified, filtered and digitized at a sampling rate of preferably only one sample per N-bit half-symbol interval. Successive N-bit half-symbols comprise information modulated alternately on a cosine and a sine carrier wave. The receiver may remove this successive rotation by applying successive derotations of successive digitized samples by like amounts. The derotated samples are then correlated with known sync half-symbols. The sync correlations determine a set of channel coefficients describing the dependence of each digitized sample on one or more unknown half-symbols. The computed channel estimates are then used to predict the expected received sample values for all possible sequences of successive unknown half-symbols that are to be decoded. Received samples are then compared with all possible expected values and a measure of disagreement or error metric computed. That sequence with the lowest cumulative error metric is used to determine the decoded symbol output. In other aspects of the invention, dual mode transmitters and receivers are disclosed that enable different types of modulation to be alternatively utilized in a same apparatus.

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