Abstract: A mobile-radio system is disclosed in which it is possible to selectively monitor and interfere with calls. To this end, the base station includes an intercept device (5) whereby at least one traffic channel is can be intercepted, i.e., whereby transmissions on this channel can be intercepted or jammed. The intercept device (5) is connected to a baseband-processing portion (1).

Abstract: A method of controlling an exchange (NE), and a communications system which comprises at least one such exchange (NE) and a management system (OS). The exchange (NE) is controlled by a number of application programs. The application programs are assigned to two different control units (CONTR1; CONTR2), namely a first and a second control unit (CONTR1; CONTR2), with different operating system platforms. One part of the application programs runs on an operating system platform of the first control unit (CONTR1), which is specifically adapted for the performance of switching functions. The other part of the application programs which is assigned to the second control unit (CONTR2), runs on a universal operating system platform. In this case the application programs of the first control unit (CONTR1) cooperate with the application programs of the second control unit (CONTR2) to provide switching functions.

Abstract: The present invention concerns a method for the manipulation-proof separation of message streams, which are transmitted in the subscriber loop (3) of a communication network via a medium (30) that is common to several subscribers, where first measures (22, 43) are taken to separate the message streams for transmission via the common medium, which are identical for all message streams, and for connections between at least one subscriber (4) connected to the communication network via the common medium, and another subscriber, supplementary measures (111, 112, . . . , 11n; 42) are taken from end to end, which were agreed between these subscribers for these connections, as well as a suitable system and a suitable subscriber facility.

Abstract: In communication networks with transmission devices using analog circuitry, because of unadapted 4-wire/2-wire junctions, some of the speech of a local speaker is reflected back to the local speaker as a line echo. This line echo is neutralized by echo compensators. However, updating of the filter coefficients of the echo compensators cannot be allowed to occur unless speech of the far-end speaker is absent. Thus, recalculation of the filter coefficients must be precluded at other times. Various possibilities for detecting the speech of a local speaker are well known. According to the invention, detection of the speech of a far-end speaker is fed back to obtain an attenuation measurement of the transmission path; this received speech simulates a reduction in attenuation. From the difference between the long-time average (Aa(k+1)) and the short-time average (A(k+1)) of the attenuation, it is learned very quickly, by comparison with a threshold (THRe), whether speech is present or not.

Abstract: A switching network for switching data in the form of cells transmitted in asynchronous transfer mode is of the "multiple path, cell auto-routing and directed sub-connection" type. Detectors are provided at each output port of the switching network to detect the absence of a missing cell in a call using that output. Incident registers store in response thereto an incident indication signifying that a cell is missing and indicating the path that the missing cell must have taken from path data derived from another cell of the same call.

Abstract: The invention concerns an MCM type high-density assembly of integrated circuits having a high reliability by virtue of its design and the means employed in its implementation. The essential feature of the assembly is the presence of one or more interconnection substrates in addition to at least one substrate carrying a plurality of unencapsulated electronic chips connected to the interconnection substrate(s) by conventional microwiring techniques, preferably through one or more apertures in the substrates. The interconnection substrate(s) is or are advantageously of the multilayer type. The assembly is adapted to be encapsulated thereafter in a hermetically sealed case in the manner that is standard for MCM.

Abstract: A wireless local area network includes a plurality of stations each comprising a data processing machine connected to a radio send-receive interface. Each data processing machine includes an interface controller for sending a message containing an address designating a destination station and for receiving messages addressed to it. The network further includes a repeater including a radio send-receive interface connected to a radiating cable passing near all the stations to receive all messages sent by the stations, to modify these messages to indicate that the message has passed through the repeater and to retransmit these messages over the radiating cable. The radio send-receive interface of each station ignores any messages not sent by the repeater. The wireless local area network finds an application in computer networking.

Abstract: A device for coupling optical fibers to a laser array comprises a flat plate (1) with a number of V-grooves (7) and a cover (2) with a number of V-shaped grooves (8), the plate (1) and the cover (2) being fitted and adjusted to each other in such a way that the grooves (7, 8) form channels with a rhombic cross section. In these channels of such a device, pointed optical waveguides (4) may be pushed to a stop (9, 10), and may then be automatically adjusted to a laser array (3) that may be arranged on the plate (1) or cover.

Abstract: A method for equalizing power levels of channels of an optical frequency division multiplexed signal determines the power level of each channel of the optical frequency division multiplexed signal and introduces attenuation into the channels having high power levels corresponding to the difference between a level deduced from these high levels and a low reference level. The equalization system includes at least one optical equalizer module which measures the optical power levels of the channels of the signal to be monitored, a processor for implementing the method and variable attenuators controlled by the processor and operating separately on the power levels of the channels.

Abstract: A process to decrease the strength of an electric field produced by a high voltage conductive path on a printed circuit board and printed circuit assembly using same includes the steps of coating the upper side (5) of the conductive path or track (1) with a thick layer of electrically conductive coating material (4); and reflowing so that the upper edges (8, 9) of the track (1) are also covered with a relatively thick layer of coating material. The track (1) is thus embedded in a mass of coating material having more or less a rounded-shaped cross-section and the sharp upper edges (8, 9) of this track, where a strong electrical field is generally produced, are smoothed. As a result, the strength of the electrical field around the track (1) is reduced. In a preferred embodiment, a second track (13) similar to the first track (1) is created symmetrically thereto on the opposite surface (14) of the printed circuit board (3).

Abstract: The present invention relates to an apparatus for exchanging information between integrated circuit identification cards, also called smart cards, and a terminal device. The circuit solution disclosed herein allows the solution of the problem of interfacing between microprocessor and smart card, in full compliance with international standard IS07816-3, through the use of low cost components. It uses a bidirectional buffer circuit and a control device so as to control information exchange between the smart card and a terminal device so that the microprocessor handles fast events and the card handles other events.

Abstract: A method for the differential coding and decoding and related circuits wherein the differential coding is a special type of coding which, instead of coding directly an input signal, carries out the difference between this signal and a predicted signal of it. This allows the reduction of the information to be transmitted. The method is capable of further reducing the signal redundancy and therefore the information to be transmitted.

Abstract: To allocate a number of data elements which constitute a data symbol to a set of carriers used for transmission in multicarrier applications, a full capacity step and capacity fine tuning step are executed successively. In the full capacity step, the individual capacity or maximum amount of data elements that may be allocated to a carrier is determined for each carrier which forms part of the set of carriers. This maximum amount of data elements is then allocated to each carrier in such a way that a full capacity occupation of the carrier set is obtained. In case of undercapacity, i.e. in case more data elements have to be allocated to the set of carriers, the capacity of the carrier set is enlarged, for example by power boosting, and additional data elements are allocated to the carriers in accordance to a predetermined rule. In case of overcapacity on the other hand, data bits previously allocated to the set of carriers, are removed from some carriers selected in accordance with another predetermined rule.

Abstract: To provide an interactive video service, a system is disclosed comprising a video server (VOD), an integrated services digital network (ISDN), and customer premises equipment (END) with a video telephone (TEL). The video server (VOD) has a memory (MEMO) in which a number of video signals, e.g., newscasts, are stored, as well as a transmitting unit (SEN) and a receiving unit (EMP), by means of which it is connected with the video telephone (TEL) via the integrated services digital network (ISDN). Via the video telephone (TEL), the customer calls the video server (VOD) to establish a switched connection, and selects from among a number of video signals available. By means of a control unit (CTRL) in the video server (VOD), the selected video signal is read from the memory of the video server and transmitted in real time over the switched connection to the video telephone (TEL). The customer can release the connection at any time, whereby the transmission of the video signal is stoppped.

Abstract: The demodulation of data modulated on a set of carriers with equidistant frequencies by a plurality of transmitters (T1 . . . Tn) is executed in the present transmission system (TS) by a discrete multitone receiver (DMT-R). The transmitters (T1 . . . Tn) in the transmission system (TS) modulate their data on subsets of carriers which form part of the set of carriers with equidistant frequencies. These transmitters (T1 . . . Tn) are possibly additionally equipped with a cyclic prefix adder (CPA); synchronization between them is guaranteed if a predefined condition is fulfilled.

Abstract: The method is used in an optical transmission network with a plurality of terminal stations (TS1-TSn) connected to a central station (CS) via a tree-like connection structure, to determine a signal transmission delay time between one terminal station (TSi) and the central station. The terminal stations are adapted to send cells containing information signals to the central station in dedicated time slots.

Abstract: An apparatus for recording speech for subsequent generation of a text includes an acoustic input (M) and an acoustic output (L) for inputting and outputting analog speech respectively. An analog-to-digital/digital-to-analog (AD/DA) converter converts the inputted analog speech into a digitized speech and converts digitized speech into analog speech. A preprocessor (VV) preprocesses the digitized speech converted by the converter (AD/DA), and extracts spectral component characteristics from the digitized speech. A digital memory (MEM) stores the digitized preprocessed speech and a controller (CON) controls an execution of inputted operating functions by at least one of the preprocessor and the digital memory.

Abstract: Telecommunications systems are often built by interconnecting similar subsystems, to enable the adaptation of the systems to different numbers of subscribers. Such a structure must fulfill the requirement that a subscriber with a cordless terminal can move freely within the area served by the telecommunications system without interrupting the call, regardless of which subsystem serves his radio cell at the moment. An uninterrupted hand-off requires the digital information to be frame synchronized. By measuring the time difference (.DELTA.t2) between the frame synchronization pulse (FR1) of a subsystem and the frame synchronization pulse (RFR2) which is recovered by an adjacent subsystem, a delay time interval can be calculated, taking the signal propagation time (.DELTA.T) between the subsystems into account, so that any frame offset is equalized. The method can be used for systems which operate according to the DECT standard.

Abstract: A coupling structure couples an optical termination (T1/T5) of an optical fiber conductor (F1/F5) to an optical terminal (T1'/T5') of an optical device which can be another optical fiber conductor. The structure includes a carrier (S, P) wherein the optical fiber conductor is embedded therein to have at least one locally bent portion reaching an outer surface of the carrier and forming there the optical termination. The carrier includes a first positioning device (P) to correctly position the optical termination with respect to the carrier and a second positioning device (L1-L3) which cooperates with a third positioning device (s1, s2, s3) of an optical arrangement including the optical device to provide the coupling.

Abstract: The present invention discloses a cell switching network which includes a cell switch (AS) coupled to a first terminal (T1) and a function unit (FU). The cell switch is also coupled to a second and a third terminal (T2,T3) via a cell switching access network (AAN). The first terminal exchanges information with the second terminal via the function unit (FU) and a predetermined part of the information is indicative of the information exchange between the first and the second terminal. The function unit is adapted to process the information and modifies the above predetermined part of the information so that it becomes indicative of information exchange between the function unit and the third terminal. The information is thereupon exchanged between the first and the third terminal via the function unit.