Abstract: A system (SYS) for optically transmitting information, e.g., television signals, from a subcenter (HUB), e.g., a cable television head end, over a passive optical distribution network to a plurality of optical network units (ONU) includes a plurality of nodes (K1, . . . , Km) for optically transmitting further information, e.g., telephone signals, and a plurality of optical couplers (C1, C2). The further information of each node (K1, . . . , Km) is fed via a respective coupler (C1, C2) into a transmission line connected to only part of the plurality of optical network units (ONU), e.g., to only one optical network unit (ONU). Each optical network unit (ONU) is connected to a group of customer locations (END) and, for the transmission of information from this group of customer locations (END), via a further passive optical distribution network to a node (K1, . . . , Km). Each node (K1, . . . , Km,) includes means for separating the information received from the customer locations into, e.g.

Abstract: A system (SYS) for optically transmitting information, e.g., television signals, from a subcenter (HUB), e.g., a cable television head end, over a passive optical distribution network to a plurality of optical network units (ONU) includes a plurality of nodes (K1, . . . , Km) for optically transmitting further information, e.g., telephone signals, and a plurality of optical couplers (C1, C2). The further information of each node (K1, . . . , Km) is fed via a respective coupler (C1, C2) into a transmission line connected to only part of the plurality of optical network units (ONU), e.g., to only one optical network unit (ONU). Each optical network unit (ONU) is connected to a group of customer locations (END) and, for the transmission of information from this group of customer locations (END), via a further passive optical distribution network to a node (K1, . . . , Km). Each node (K1, . . . , Km,) includes means for separating the information received from the customer locations into, e.g.

Abstract: A system (SYS) for optically transmitting information, e.g., television signals, from a subcenter (HUB), e.g., a cable television head end, over a passive optical distribution network to a plurality of optical network units (ONU) includes a plurality of nodes (K1, . . . , Km) for optically transmitting further information, e.g., telephone signals, and a plurality of optical couplers (C1, C2). The further information of each node (K1, . . . , Km) is fed via a respective coupler (C1, C2) into a transmission line connected to only part of the plurality of optical network units (ONU), e.g., to only one optical network unit (ONU). Each optical network unit (ONU) is connected to a group of customer locations (END) and, for the transmission of information from this group of customer locations (END), via a further passive optical distribution network to a node (K1, . . . , Km). Each node (K1, . . . , Km,) includes means for separating the information received from the customer locations into, e.g.

Abstract: A system (SYS) for optically transmitting information, e.g., television signals, from a subcenter (HUB), e.g., a cable television head end, over a passive optical distribution network to a plurality of optical network units (ONU) includes a plurality of nodes (K1, . . . ,Km) for optically transmitting further information, e.g., telephone signals, and a plurality of optical couplers (C1, C2). The further information of each node (K1, . . . , Km) is fed via a respective coupler (C1, C2) into a transmission line connected to only part of the plurality of optical network units (ONU), e.g., to only one optical network unit (ONU). Each optical network unit (ONU) is connected to a group of customer locations (END) and, for the transmission of information from this group of customer locations (END), via a further passive optical distribution network to a node (K1, . . . , Km). Each node (K1, . . . , Km,) includes means for separating the information received from the customer locations into, e.g.

Abstract: Line equipment, preferably a line terminating device, in a communications system including transmitting and receiving circuits to which are connected transmitting lines and receiving lines includes at least one receiving circuit that is equipped with a circuit arrangement for compensating crosstalk. A single circuit arrangement effects the compensation of crosstalk between a plurality of transmitting lines and a receiving line. For compensation, a reference signal of the transmitted signal is branched off from each transmitting circuit and an adaptive filter simulates a compensation signal. The individual compensation signals are mixed into the received signals through the subtraction inputs of a subtraction circuit. Part of the output signal of the subtraction circuit is fed to the control signal inputs of the adaptive filters, the other part is processed further to become the received signal.

Abstract: The network access node of a digital communication system for the bidirectional transmission of message signals between, for example, a switching center and subscribers as an electrically switchable connection between the lines to the switching centers with a first interface and the lines to the subscribers with a second interface. The first interface is preferably an interface for a time-division multiplex signal with a transmission rate of 2 Mbit/s; the second interface is preferably an interface for signals in multiple access with time-division multiplex (TDM/TDMA). The buffer memory of the TDM/TDMA system is made up of partial memories arranged as a matrix. The partial memories are used simultaneously as a buffer memory for the circuit of the paths.

Abstract: A fast adjustment of sampling clock phase may be accomplished by calculating the values of the pre-oscillations and post-oscillations that would have been present at each sampling instant to form a correction value so that they may then be subtracted from the measured sample value and only the influence of the distorted unique word remains. Usable control information for readjusting the phase of the sampling clock may thus be derived after only one frame synchronization word has been detected. In a preferred embodiment, the required pre-oscillation and post-oscillation values are derived from the regenerated character data; rather than correcting the sample values themselves, correction values are derived which are used to correct quantities derived from the sample values.

Abstract: With such a circuit arrangement, the sampling clock is synchronized to the frame position and the phase of the characters of a received character stream containing a "unique word" at regular intervals. In a digital correlator (1), a crosscorrelation function is generated from a unique word stored therein and from the received, sampled character stream, and a frane detection circuit (2) derives a frame clock (RT1) from those maxima of the crosscorrelation function recurring at intervals of one frame period. To achieve synchronization at any polarity of the received character stream (i.e., even if the tip and ring wires of the subscriber line are interchanged), a second frame detection circuit (3) derives a second frame clock (RT2) from those minima of the crosscorrelation function recurring at intervals of one frame period. A clock selection circuit (8) determines which of the two frame clocks is received within a limited time interval.

Abstract: For locating faults in digital telecommunication subscriber terminations various test loops (A, B, C) are closed and checked by signals transmitted via the exchange (16). When a fault is proved to exist in the so-called C-loop, it cannot be detected whether the fault is in the subscriber line (2) or in the network termination (1). In order to be able to distinguish between the two sources of fault, and when the subscriber line (2) is in an unobjectionable state, the filter coefficients which are continuously adjusted in a recursive filter contained in the echo canceller (24) of the subscribers group circuit (17), are stored. Since, in the case of a faulty subscriber line (2), the echo canceller (24), based on the received pulse answer, adjusts changed filter coefficients, it is possible to localize the location of fault by way of comparing the continuous coefficients with the stored coefficients.

Abstract: An electronic switch comprised of a C-MOS transistor is described. Associated with this transistor is a network consisting of MOS transistors which prevents the C-MOS transistor from being inadvertently turned on as a result of negative input voltages in the absence of bias voltages. When a plurality of C-MOS transistors of the disclosed configuration are utilized as switching elements of a matrix each such matrix is allotted one such network.

Abstract: An electronic switch including a MOS transistor is disclosed wherein a monitoring circuit is allotted which when the bias of the MOS transistor fails prevents negative input voltages from unintentionally turning on the MOS transistor. When a plurality of MOS transistors are used as switching elements each matrix is allotted one monitoring circuit, each of which includes a MOS transistor.

Abstract: An electronic switch arrangement reverses damping of an electronic switching element by means of a controllable negative resistance. Adjustment of the negative resistance is provided by comparing a measuring current through the arrangement to a preselected reverse current.

Abstract: An electronic resistance arrangement having symmetrical structure and properties comprises four series-connected negative-resistance elements having negative feedback operational amplifiers. A measuring current can be fed to the center of the arrangement whereby both halves of the arrangement can be independently controlled for compensating a resistance.