公开(公告)号：EP0187339A3

公开(公告)日：1988-07-13

申请号：EP85116251

申请日：1985-12-19

Applicant: GTE Laboratories Incorporated

Inventor： Cooperman, Michael

IPC: H04L05/14

CPC classification number: H04L5/1484

Abstract: @ A low power line driving transmission apparatus is described in which TDM signals are transmitted between points over a transmission line comprising a pair of conductors and in which the characteristic impedance of the transmission line and the source impedance of the transmitters is matched and wherein the input impedance of the receivers is sufficiently high to present an effective open circuit to received signals. Under these conditions the transmitter dissipates power only during logical transitions of the input signals.

公开(公告)号：EP0176098A3

公开(公告)日：1987-09-02

申请号：EP85112194

申请日：1985-09-26

Applicant: FUJITSU LIMITED

Inventor： Fukua, Misao ,  Tsuda, Toshitaka ,  Murano, Kazuo

IPC: H04L05/14 ,  H04L05/16

CPC classification number: H04L5/1423 ,  H04L5/1492

Abstract: A digital transmission system comprising at least two transmitting-receiving (T/R) units (40,50) and a single transmission line (30) connected therebetween. One of the T/R unit (40) transmits a control signal to the other T/R unit (50) in which a frame synchronization and timing recovery is carried out with the use of the thus transmitted control signal. At the same time, the other T/R unit (5) inhibits transmission of an own side send signal to the first T/R unit (40). Further, the send signal from one T/R unit to the other T/R unit is transmitted in the form of a frame. Each frame includes, at its end portion, a non-signal duration part.

公开(公告)号：EP0067310A3

公开(公告)日：1984-02-15

申请号：EP82104116

申请日：1982-05-12

Applicant: International Business Machines Corporation

Inventor： Mueller, Mark Wayne ,  Parker, Thomas Shelton

IPC: H04L05/14 ,  H04L01/10

CPC classification number: H04L5/1423 ,  H04L1/0083

Abstract: A communication adapter circuit (10) is connected to a processor through processor I/0 interface buses (12, 14). Data and control signals are provided through the buses (12, 14) to a timer circuit (18), a programmable peripheral interface circuit (20), an asynchronous and bisynchronous control circuit (22) and an SDLC/HDLC control circuit (24). Each of the control circuits (22, 24) includes parallel-to-serial and serial-to-parallel conversion circuitry. A clock select circuit (32) operates in conjunction with the timer circuit (18) and the programmable peripheral interface circuit (20) to establish a data transmission rate for the data flow through the adapter circuit (10). From the control circuits (22, 24) the data is transmitted through a modem interface bus (44) to a dual modem switch (56). From the switch (56) the data is transmitted to either an EIA RS 232 interface circuit (60) to a conventional modem or through a bus (64) to an internal modem. A phase locked loop circuit in the control circuit (24) generates a data clock signal on a line (33) for operation of the adapter circuit (0) in the bisynchronous protocol with a non-clock-generating modem.

公开(公告)号：EP0069595A3

公开(公告)日：1983-02-09

申请号：EP82303552

申请日：1982-07-07

Applicant: GENERAL DATACOMM INDUSTRIES, INC.

Inventor： Shum, Martin N.Y.

IPC: H04L05/14 ,  H04B07/015 ,  H04B07/185 ,  H04B03/20 ,  H04B07/15

CPC classification number: H04B3/20 ,  H04L5/16

Abstract: This invention relates to a method and apparatus providing a common handshaking protocol for the 201, 202 and 208 modems in long distance data transmission. According to the present invention a novel handshaking sequence trains up any echo canceller 74 in the circuit, detects the presence of any echo suppressor 82 and uses a conventional signal preamble in the presence of echo cancellers 74 and a sacrificial carrier sequence in the presence of echo suppressors 82. As in the prior art, a ringing signal is applied to an answer modem 40 in response to a signal from an originate modem 30. The answer modem 40 is connected to the communication line after receipt of the ringing signal, and an answerback tone is transmitted from the answer modem to the originate modem after a period of silence following connection of the answer modem to the line. After receipt of the answerback tone, the originate modem 30 is connected to the communication line. In accordance with the invention, this is followed by a period of silence that is sufficiently long to reactivate any echo suppressors 82 in the communication line. Thereafter at least two training sequences are transmitted, one from the originate modem 30 to the answer modem 40 and the other from the answer modem 40 to the originate modem 30, each training sequence being sufficiently long to train up any echo canceller 74 in the line. The lengths of the training sequences as received are compared with their lengths as transmitted to determine if the length of the sequence was shortened by an echo suppressor 82. If the length of the training sequences as received are significantly shorter than their lengths as transmitted, a sacrificial carrier is transmitted at the beginning of each transmission of data in a new direction. In the event the training sequences as received are not significantly shorter, each transmission of data in a new direction begins without a sacrificial carrier. As a result, greater data throughput can be achieved in the absence of echo suppressors 82 and errors can be avoided while echo cancellers 74 are being trained.

公开(公告)号：EP0157704A3

公开(公告)日：1988-03-30

申请号：EP85400620

申请日：1985-03-29

Applicant: ALCATEL N.V.

Inventor： Upp, Daniel Clay

IPC: H04L05/14 ,  H04B03/54

CPC classification number: H04B3/548 ,  H04B2203/5425 ,  H04B2203/5437 ,  H04B2203/547 ,  H04L5/1423

Abstract: A duplex digital transmitter system is disclosed which permits simultaneous digital signal exchange over a two-wire loop. Two sets are provided at the ends of the loop, each having a three-port lattice adapted to separate the transmitted and received digital signals. The digital signals are encoded using a biphase scheme so that they have a zero D.C. component. Therefore the loop is used simultaneously to transmit D.C. power from one set to the other.

公开(公告)号：EP0098260A3

公开(公告)日：1985-10-30

申请号：EP83890102

申请日：1983-06-17

Applicant: VOEST-ALPINE Aktiengesellschaft

Inventor： Posch, Reinhard Dr.

IPC: H04L05/14

CPC classification number: H04L5/143 ,  G06F13/124 ,  G06F13/4221

公开(公告)号：EP0058764A3

公开(公告)日：1983-09-07

申请号：EP81109424

申请日：1981-10-30

Applicant: Siemens Aktiengesellschaft

Inventor： Anders, Alois, Dipl.-Ing.

IPC: H04B09/00 ,  H04L05/14 ,  H04B01/00

CPC classification number: H04B10/2503 ,  H04B14/006 ,  H04L5/143

Abstract: Die Erfindung bezieht sich auf ein Nachrichten übertragungssystem mit einer Übertragung in beiden Über tragungsrichtungen jeweils in einer anderen Frequenzlage. Erfindungsgemäß sind die Sendeteile (1, 13) und die Emp fangsteile (4, 17) beider Endstellen (I, II) über optische Ver zweiger (8, 10) mit einer einzigen Lichtleitfaser (9) als Über tragungsmedium verbunden. Optische Überkopplungen zwischen den Abzweigungs-Anschlüssen der optischen Verzweiger (8, 10) werden durch ein Filter (5, 16) im benach barten Empfanggsweg eliminiert. Als Sendeteile (1, 13) und Empfangsteile (4, 17) können beispielsweise Trägerfre quenzsysteme Z12 oder Z60 dienen. Zwischenstel len (III) können entsprechend mit optischen Verzweigern (18, 23) und Filtern (19, 22) ausgerüstet werden. Das erfindungsgemäße System ist besonders für Elektrizitäts versorgungsunternehmen geeignet, da ein Kabel mit Licht leitfasern unmittelbar von Störspannungen unbeeinflußt ne ben Stromversorgungsleitungen verlegt werden kann und gleichzeitig die vertrauten Trägerfrequenzsysteme einge setzt werden können.

公开(公告)号：EP0079527A3

公开(公告)日：1983-06-29

申请号：EP82110146

申请日：1982-11-04

Applicant: TE KA DE Felten & Guilleaume Fernmeldeanlagen GmbH

Inventor： Bader, Edgar, Dipl.-Ing. ,  Rohrbach, Gerd, Dipl.-Phys. ,  Petersen, Jürgen, Dipl.-Ing. ,  Kittel, Ludwig, Dr.

IPC: H04L05/14 ,  H04L07/02

CPC classification number: H04L7/0008 ,  H04L5/1423 ,  H04L7/0331

公开(公告)号：EP0185610A3

公开(公告)日：1988-03-09

申请号：EP85730170

申请日：1985-12-20

Applicant: Angewandte Digital Elektronik GmbH

Inventor： Jenning, Michael ,  Mackenthun, Holger

IPC: H04B05/00 ,  H04L05/14 ,  H04L27/18

CPC classification number: H04L27/2331 ,  G06K7/0008 ,  G06K19/0723 ,  H04B5/00 ,  H04B5/0031 ,  H04B5/0037 ,  H04B5/0087 ,  H04L5/143

公开(公告)号：EP0175656A3

公开(公告)日：1988-01-07

申请号：EP85830225

申请日：1985-09-09

Applicant: ISTRUMENTI DI MISURA C.G.S. S.p.A.

Inventor： Fedrigo, Renzo ,  Fere, Franco

IPC: H04L05/14 ,  G08C19/02

CPC classification number: H04L5/1423 ,  G08C19/02 ,  G08C19/025

Abstract: @ A monitoring unit supplied with a signal to be measured which can control the operation of actuator elements such as electro-mechanical relays, is connected through a single transmission line to a visual display unit for the presentation of the signal to be measured in visual form. The visual display unit has associated regulating elements which allow threshold values of the signal to be selected (for example minimum and maximum values) in correspondence with which it is wished to vary the operating conditions of the said relays. Indicator lights associated with an indicator module indicate the operating conditions of these actuator elements. The monitoring unit includes a power source which causes an electrical current flow in the transmission line, the average magnitude of which represents the value of the signal being measured. The visual display unit on the other hand includes a current meter which is sensitive to the current flowing in the transmission line and comparator elements, the switching threshold of which is at a level which can be selected by means of regulating members. When the signal being measured reaches one of these treshold levels, a voltage generator in the visual display unit applies a corresponding voltage to the transmission line. This voltage is detected by a voltage meter present in the monitoring unit. The voltage meter acts on a corresponding relay causing it to change its state. Furthermore, an auxiliary oscillator associated with the voltage meter passes a pulse signal into the transmission line through the current generator with an average value of zero, this pulsed signal being receveid by the visual display unit and activating the corresponding indicator light. The remote supply of the visual display unit is provided for by an alternating current signal with an average value of zero fed through the transmission line.

Abstract translation: 提供有可以控制诸如机电继电器的致动器元件的操作的待测量信号的监视单元通过单个传输线连接到视觉显示单元，用于以视觉形式呈现要测量的信号。 视觉显示单元具有相关联的调节元件，其允许选择信号的阈值（例如最小值和最大值），与之相对应地希望改变所述继电器的操作条件。 与指示器模块相关的指示灯指示这些执行器元件的操作条件。 监测单元包括电源，其在传输线中引起电流流动，其平均值表示被测信号的值。 另一方面，视觉显示单元包括对在传输线路中流动的电流敏感的电流表和比较器元件，其切换阈值处于可以通过调节构件选择的水平。 当测量的信号达到这些阈值电平之一时，视觉显示单元中的电压发生器向传输线施加相应的电压。 该电压由监视单元中存在的电压表检测。 电压表作用在相应的继电器上，使其改变其状态。 此外，与电压表相关联的辅助振荡器通过电流发生器将脉冲信号传递到平均值为零的电流发生器，该脉冲信号由视觉显示单元接收并激活对应的指示灯。 视觉显示单元的远程供应由通过传输线馈送的平均值零的交流信号提供。