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1.发明公开Coded modulation system with a simplified decoder capable of reducing the effects of channel distortion 失效具有简化的解码器的编码调制系统可以减少通道失真的影响
公开(公告)号：EP0206770A3
公开(公告)日：1988-09-28
申请号：EP86304724
申请日：1986-06-19
Applicant: CODEX CORPORATION
Inventor： Eyuboglu, Vedat M.
CPC classification number: H04L1/0052 , H03M13/25 , H04L1/0054 , H04L1/0058 , H04L1/0065 , H04L25/03057 , H04L27/3438
Abstract: A receiver for deciding which signal points were sent from a transmitter based on corresponding noise affected signals received via a distorting channel, the noise affected signals carrying information about a particular sequence of encoding states occupied in a succession of time intervals by a finite state process having a finite number of possible encoding states, the receiver including modifying circuitry for generating a plurality of different modified versions of each received signal, and a decoder for deciding which signal points were sent based on estimating a particular sequence of decoder states by storing a number of path histories of previous signal points and using the modified versions to , extend the path histories, the different modified versions of each received signal numbering fewer than the number of stored path histories. In other aspects, the constellation of signal points is partitioned into decision subsets, each possible transitions from a possible decoder state are associated with a decision subset, based on the signal points in the path histories, and each of the modified versions is associated with one of the decision subsets; there are fewer modified versions than the number of decoder states; and the decoder states number fewer than the number of decoder states in an optimum trellis decoder.
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2.发明公开
公开(公告)号：EP0200505A3
公开(公告)日：1988-09-14
申请号：EP86303165
申请日：1986-04-25
Applicant: CODEX CORPORATION
Inventor： Wei, Lee-Fang
CPC classification number: H04L1/0058 , H03M13/25 , H04L1/0052 , H04L1/0054 , H04L1/0065 , H04L1/0072 , H04L27/3438
Abstract: Embodiments of apparatus are described for transmitting a stream of information bits by sending corresponding signals over a channel in a plurality of signalling slots. A family of multi-dimensional convolutionally coded modulation systems achieves enlarged minimum distance between possible sequences of signal points, reduced number of error events with the minimum distance, acceptable peak-to-average power ratio, reduced number of signal points in each constituent two-dimensional constellation, immunity to rapid carrier phase changes, and reduced complexity, resulting in a reduced error probability when maximum likelihood decoding is used. These advantages are achieved by the construction and by the partitioning into subsets of the multi- dimensional constellation, by the design of convolutional codes using those multi-dimensional subsets, by using a bit converter and a block encoder to convert a multi-dimensional constellation mapping into multiple two-dimensional constellation mappings, and by a simplified decoding technique.
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3.发明公开
公开(公告)号：EP0030628A3
公开(公告)日：1981-09-16
申请号：EP80107062
申请日：1980-11-14
Applicant: Siemens Aktiengesellschaft
Inventor： Günther, Rudolf, Dipl.-Ing.
IPC: H04L01/00 , H03K13/32 , H03K13/258
CPC classification number: H04L1/00
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公开(公告)号：EP0186420A3
公开(公告)日：1988-10-05
申请号：EP85309199
申请日：1985-12-17
Applicant: ADVANCED MICRO DEVICES, INC.
Inventor： Bemis, Gerald L.
CPC classification number: H04L12/433
Abstract: A code conversion system is described for converting a stream of data between first and second data codes. The stream of data containing data packets is recognized to be subject to a data fault condition arising from the collision of data packets. The conversion system comprises means for detecting the fault condition, and means for altering the code conversion of the stream of data between the first and second codes so as to reflect the occurrence of the fault condition in the code converted stream of data.
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5.发明公开
公开(公告)号：EP0227389A3
公开(公告)日：1987-11-04
申请号：EP86309686
申请日：1986-12-11
Applicant: Dolby, Ray Milton
Inventor： Dolby, Ray Milton
CPC classification number: G11B27/36 , G11B20/182
Abstract: An audibly distinctive test signal provided by a generator (6) is a pink noise signal at a standard level with periodic but brief interruptions (optimized for the ear's memory for level and spectral differences) acting as an identifier. The test signal is applied to a recording medium or transmission channel (14), preferably via an equalizer (16) and gain setting means (181. The test signal recovered from the recording medium or transmission channel by playback or receiving means (22) is compared and matched to a reference uninterrupted pink noise signal provided at a standard level by a generator (24). The interruptions are used to switch between the test and reference signals and to provide via equalizer (34) and speaker (28) an audible cue as to the identity of the signal heard at any moment so that a rapid confirmation and adjustment, if necessary, of recording/reproduction or transmis- sion/reception calibration can be achieved primarily by ear and, if desired, also by applying the signals to measuring instruments, such as a meter (30) and spectrum analyser (32).
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Patent Agency Ranking
公开(公告)号：EP0151430A3
公开(公告)日：1987-08-26
申请号：EP85100645
申请日：1985-01-23
Applicant: HONEYWELL INC.
Inventor： Kozlik, Tony J.
CPC classification number: H04L12/417 , H04L1/0083 , H04L25/4904
Abstract: A detector of predetermined patterns of Manchester encoded data signals (PRICHL) in which the voltage levels of the half-bit cells of "n" sequential Manchester bit cells, where "n" is an integer greater than zero, are clocked into a shift register (12-1, 12-2), the pattern of 2 "n" voltage levels of 2 "n" half-bit cells of the "n" sequential Manchester bit cells stored in the register at any given time are examined by a programmable logic array (18) which produces an output signal when the pattern of outputs of the shift register corresponds to the predetermined patterns (Fig. 1).
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公开(公告)号：EP0112697A3
公开(公告)日：1986-02-26
申请号：EP83307663
申请日：1983-12-16
Applicant: PLESSEY OVERSEAS LIMITED
Inventor： Gannaway, Julian Nolan
CPC classification number: H04M11/064 , H04L1/0002 , Y02D50/10
Abstract: A communication system including a transceiver for transmitting and receiving a signal comprising a plurality of channels one of which consists of analogue speech signals and at least one other of which consists of data signals transmitted at intervals and interleaved with the speech signals, the data signals each comprising at least one complete cycle of a frequency or frequencies, which lie within the audio frequency spectrum wherein the significance of the data i.e. '0' or' 1', is defined in dependence upon its phase or frequency and wherein the data signal transmission rate is determined in dependence upon error rate detected in relation to the data signals received at a remotely located transceiver.
Abstract translation: 一种通信系统，包括用于发送和接收包括多个信道的信号的收发器，其中之一由模拟语音信号组成，并且其中的至少一个由以间隔发送并与语音信号交织的数据信号组成，数据信号各自 包括位于音频范围内的频率或频率的至少一个完整周期，其中数据即“0”或“1”的重要性根据其相位或频率来定义，并且其中数据信号传输速率 取决于相对于在位于远程的收发器处接收的数据信号检测到的错误率。
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公开(公告)号：EP0178287A3
公开(公告)日：1988-12-28
申请号：EP85890213
申请日：1985-09-06
Applicant: VOEST-ALPINE Aktiengesellschaft
Inventor： Schwingshakl, Gert, Dipl.-Ing.
CPC classification number: G06F13/4269 , H04L1/0083
Abstract: Eine Schaltungsanordnung (1) zur Kontrolle der Daten fernübertragung, welche zwischen einer Daten abgebenden ein und/oder empfangenden Einheit, beispielsweise einem Rechner (4) oder einem Endgerät (7), und einem mit einer Datenfernübertragungsleitung (6) verbindbaren Modem (5) angeordnet oder mit dem Modem (5) kombiniert ist, weist einen Datenpuffer, einen Programmspeicher, einen Mikro prozessor und einen Zeitgeber auf, wobei für den Anschluss der Daten abgebenden und/oder empfangenden Einheit eine serielle Standardschnittstelle (V24) und bei Verwendung ei nes gesonderten Modems (5) für den Anschluss desselben ebenfalls eine serielle Standardschnittstelle (V24) sowie zur Verbindung der seriellen Standarschnittstelle(n) mit dem Datenbus des Mikroprozessors ein Asynchron-Sender/Em pfänger vorgesehen sind. Der Mikroprozessor steuert in Ab hängigkeit vom Datenanfall eine zeichen- oder eine blocko rientierte Übertragung unter Voraussetzung jeweils eines Synchronisierbits, wobei die Adressierungen im sendersei tigen und im empfängerseitigen Datenpuffer synchron laufen und zur Angabe, wieviel einer empfangenen Meldung er kannt wurde, ein Zeichen ACK/NACK übertragen wird. Nach einer Anzahl K zu übertragender Zeichen sendet der Mikro prozessor ein Blockprüfzeichen BCC und bewirkt, falls zu sendende Zeichen im Pufferspeicher enthalten sind, die Übertragung bis zum K Zeichen sowie, falls keine richtige Meldung zuletzt empfangen wurde und das vorige Zeichen ein Blockprüfzeichen war, die Beendigung der Übertragung.
Abstract translation: 用于检查远程数据传输的电路装置（1），其安装在数据发送和/或接收单元之间，例如计算机（4）或终端（7）和可连接到 数据传输线（6）或与调制解调器（5）组合; 该装置具有数据缓冲器，程序存储器，微处理器和定时器; 标准串行接口（V24）用于连接发送和/或接收数据的单元，当使用单独的调制解调器（5）时，标准串行接口（V24）也用于连接所述调制解调器和异步 收发器被提供用于将标准串行接口连接到微处理器的数据总线。 微处理器根据数据的到达来控制字符取向或块取向的传输，在每一种情况下都有一个对准位，发送器端和接收端数据缓冲器中的寻址同步进行，并指示多少 识别出接收到的消息，发送ACK / NACK字符。 在要发送的K个字符之后，微处理器发送块检查字符BCC，并且如果要发送的字符被包含在缓冲存储器中，则其传输高达K个字符，并且如果最后没有收到正确的消息，并且 前一个字符是块检查字符，终止传输。
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公开(公告)号：EP0217570A3
公开(公告)日：1988-10-26
申请号：EP86306971
申请日：1986-09-10
Applicant: HYCOM INCORPORATED
Inventor： Motley, David M. , Stockman, John F.
CPC classification number: H04L1/0059 , H03M13/25 , H04L7/048 , H04L27/3433
Abstract: Error multiplication in a V.22 bis modem is avoided by using forward error correction and single symbol coding instead of differential coding. In the receiver section (25b) the error syndrome bit of the error corrector (32) is used in establishing phase and timing synchronization by causing the symbol detector (26) of the receiver (25b) to try all possible combinations of phase and timing, and to lock onto the combination which produces a minimum of error syndrome bits. The descrambler (30) receives the error-free corrected bit stream.
Abstract translation: 通过用前向纠错和单符号编码代替差分编码，避免了V.22双调制解调器的差分解码器和解扰器中的误差乘法。 错误校正器的误差校正位用于通过使接收机尝试所有可能的相位和定时组合并锁定到产生最小误差校正位的组合来建立相位和定时同步。 解扰器接收无错误的纠正比特流，由此解扰器的固有误差乘法变得不成立。
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公开(公告)号：EP0179465A3
公开(公告)日：1988-07-06
申请号：EP85113477
申请日：1985-10-23
Applicant: NEC CORPORATION
Inventor： Yoshimoto, Makoto
CPC classification number: H04L1/24
Abstract: A channel quality monitoring apparatus provided in terminal equipment of a digital radio communication system comprises a syndrome generator circuit (10-13) responsive to a digital multiplexed signal of a receiving signal, a signal converter circuit (14) for converting an error-corrected digital multiplexed signal into a digital multiplexed signal with which a predetermined parity detection is possible. a parity detector circuit (15) for effecting a parity detection of the digital multiplexed signal from the signal converter circuit (14), and computing circuitry configured as an error rate detector circuit (16) responsive to outputs from the syndrome means (10-13) and the parity detector circuit (15). When occurrence of code error detected on the basis of the syndrome continues for the duration more than a predetermined time period, the computing circuitry is operative to compute an error rate of the receiving digital multiplexed signal on the basis of the syndrome. In contrast, when occurrence of code error detected continues for the duration equal to or less than the predetermined time period, the computing circuitry is operative to compute an error rate of the receiving digital multiplexed signal on the basis of the output from the parity detector circuit (15). Thus, this apparatus provides an improved detection accuracy of a channel error rate in the equipment of receiving and demodulating systems.
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