Abstract: Telephone exchange with associated voice mail device is connected to a calling subscriber after a predetermined time if the called subscriber does not answer the call, as well as method to store such voice messages in such a device, whereby the voice mail device is able to store voice messages arriving from the calling subscriber and intended for the called subscriber and to send them to the called subscriber on his request. The telephone exchange comprises means which will also connect all further calls for the called subscriber to the voice mail device as soon as one switch-over after timeout of the called subscriber to the voice mail device has been executed. Hence, the exchange recognizes that the called subscriber is not ready to speak and switches all further arriving calls to the voice mail device.

Abstract: It is proposed that in a telecommunications network (KN) for control of mass callings to subscribers of the telecommunications network (KN) with exchanges (VST1, . . . , VST7), each of which has a control means (SM1), to perform measurements to detect a mass calling to a subscriber exclusively in those exchanges (VST1, . . . , VST5) of the telecommunications network (KN) to which a subscriber, who is the possible target of such a mass calling, is connected. The exchange (VST1) which detects the mass calling signals its occurrence to respective predetermined further exchanges (VST2, . . . , VST5, VST7) in the telecommunications network (KN). Each of the predetermined further exchanges (VST2, . . . , VST5, VST7) and the exchange (VST1) which detects the mass calling, chokes the traffic to this subscriber at a rate that is fixed for the respective predetermined further exchange.

Abstract: Known hand-held mobile radiotelephones and cordless telephones have the dimensions of a handset, and their antennas radiate near the user's head; such may be improved by providing a hand-held radiotelephone which is of a compact design and fully user-controllable and exposes the user to only little RF radiation. A hand-held radiotelephone (HH1) is provided whose earpiece (R) and/or microphone (M) are spatially separated from the other components of the radiotelephone. It is also possible to provide an infrared link between the earpiece and/or microphone and the housing of the radiotelephone in order to further increase the user's freedom of movement. During operation of the hand-held radiotelephone, the keyboard and display are fully accessible.

Abstract: The sensing circuit is used in an Asymmetric Digital Subscriber Line (ADSL) transmission system to detect a wave signal with a predetermined shape in an input signal (IN1/IN2) transmitted over the system and applied to an input terminal (IN1/IN2) of the sensing circuit. It includes two branches with a correlated double sampling circuit (CDS1/CDS2), a counter circuit (C1/C2) and a comparator circuit (CMP1/CMP2) coupled in series. An input (IN1/IN2) of the correlated double sampling circuit of each branch is coupled to the input of the sensing circuit and an output of the comparator circuits is coupled to an output terminal (OUT) of the sensing circuit via an OR-ing circuit. The correlated double sampling circuits are adapted to provide a sampled signal and the counter circuits count the number of pulses of the sampled signals.

Abstract: The essential functions and characteristics of a telecommunications system with cordless terminals are established by the known DECT standard. On the one hand, the invention has the task of reducing the cost of ADPCM/PCM transcoders in DECT or DECT-like systems, and on the other to improve the handover characteristics, by making an interruption-free channel changeover, even during a change of cell bundles. To that effect, all DECT interface circuits (9, 10) are jointly controlled by a central processing unit (MOB CPU) assigned only to these DECT interface circuits (9, 10). The otherwise usual ADPCM/PCM transcoders have been omitted in the DECT interface circuits (9, 10), and are now assigned to the central processing unit (MOB CPU), while their number can be reduced in comparison to known solutions. The central processing unit (MOB CPU) also takes over the switching functions for the channels offered by the DECT interface circuits (9, 10).

Abstract: An optical duplexer, configured as a directional coupler, is integrated into an optical coupling arrangement with a fiber optic pigtail, constructed in planar-optical hybrid technology on a substrate (1). To reduce the required surface area and decrease optical cross talk, the branch of the directional coupler (waveguide 6, branch 7) is sharply bent. The bend is equipped with a reflecting mirror (11) integrated opposite the inner edge (10) of the bend. Furthermore, the waveguiding end of the bent branch (7) is equipped with a cylindrical lens. A laser diode (8) is located before this, and a photodiode (5) is located before the angled end of the straight-line integrated waveguide (2).

Abstract: A vending apparatus (AUT) is used to sell data records. The vending apparatus comprises a payment device (PAY), a control device (CONTR), a device for limiting the extent of utilization (RESTR), and an interface device (INTER1). The interface device (INTER1) sends a release signal to the control device (CONTR), when a suitable memory device (MEM2) is coupled to it in such a way, that a data transfer becomes possible. The device for limiting the extent of utilization (RESTR) only permits the storage of data records in the memory device (MEM) to a predetermined extent. The control device (CONTR) causes the transmission of at least one to be sold data record to the device for limiting the extent of utilization (RESTR), if it receives a release signal from the payment device (PAY) and the interface device (INTER1).

Abstract: A train radio system with a simple network structure that is suitable for a safe radio transmission. The train radio system comprises radio stations (R), which are arranged along a route, and a mobile station (MS) which is mounted in a vehicle moving along the route, and comprises a transceiver (TRX) and a data bank (HLR) that is connected thereto, into which identification codes (IDn, IDn+1) for the radio stations (R) can be entered. A signalling channel (ACH) is provided, through which each radio station (R) transmits its identification code to the mobile station to establish the radio link for checking into the data bank (HLR). In this way the mobile station (MS) forms a single traveling radio cell to provide radio to those radio stations (R) that are located inside this radio cell. The infrastructure, which essentially comprises the radio stations, can be realized simply and requires no costly network structure.

Abstract: A device for receiving a source digital signal transmitted at one or more source symbol frequencies F.sub.s samples a received analog signal transposed into the baseband and delivers an entirely demodulated sample signal. The sampling frequency F.sub.e complies with the generalized sampling condition. A single filter module filtering the sampled signal comprises a digital filter controlled by a filter coefficient vector. The filter coefficients are determined according to a determination criterion allowing for the ratio of the sampling frequency F.sub.e to the source frequency F.sub.s, to interpolate the sampled signal, and for an analysis of the transmission path, in order to limit interference introduced by the path.

Abstract: To enable testing of lightly loaded, remote base stations 2, a mobile phone 3 located within the cell is programmed to dial a test number via the public switched telephone network (PSTN). The test number generates an audio signal, e.g. a fixed tone which is transmitted to the mobile phone. A test unit 4 is connected to the mobile phone and initiates the test program and monitors receipt of the audio signal. Test unit 4 includes control logic 5 connected via a communication link 54 to a base station 2, and via lines 51, 52, 53 to phone 3. A tone monitor 7 tells control logic 5 whether a radio downlink test tone has been received, and the result is stored in a memory 11. A second tone generator 8 can be actuated by control logic 5 to test a radio uplink from phone 3 to base station 2.

Abstract: The method is used in a system comprising a central station (CS) coupled to each of a plurality of terminal stations (TS1-TSn), wherein the central station (CS) is enabled to transmit downstream frames (DS) to the terminal stations to allow the terminal stations to transfer upstream frames (US) to the central station in time slots assigned thereto by way of of access grant information (TEA1-TEA4) included in the downstream frames. The downstream frame (DS) is a superframe having a matrix structure with rows and columns, and a first portion and a second portion of the matrix structure is an overhead portion (S, TCB) and an information portion (ATM) respectively. The overhead portion includes the access grant information and the size of the overhead portion is flexibly adaptable. The central station and the terminal stations are adapted to send and to interpret the superframe.

Abstract: The invention relates to a system for distributing amplified optical signals, the system comprising an optical star coupler having at least two inputs, each input of said coupler being connected to the output of a respective optical amplifier whose input receives an optical signal. According to the invention, said optical amplifiers are optical amplifiers whose gains are kept constant.

Abstract: In a broadband distribution system (SYS) for distributing television signals (TVS) and video signals (VOD), the return channel provided for requesting video signals is divided among the subscribers (TN) of the broadband distribution system (SYS) in such a way, that each group of subscribers (TN) is assigned a part of the return channel using time-division multiplexing, and the individual subscribers (TN) of a group have equal access to the part of the return channel assigned to the respective group. Access by the individual subscribers (TN) is monitored by a control unit (CONTROL) in the center (ZE) of the broadband distribution system (SYS). To synchronize the signals transmitted by the subscribers (TN) over the return channel using time-division multiplexing, the center (ZE) has a synchronizer (SYNC) which compensates for phase differences produced by differences in transit time.

Abstract: Generating, sending, receiving and commenting a text document via a telecommunication installation. A text document is generated by means of speech and converted into text data by a speech recognizer (SEK). The text data can be corrected, edited and commented by means of speech. Transmission is automatic via the telecommunication installation (VA).

Abstract: In digital transmission systems, such as synchronous transmission systems according to the SDH/SONET standard, there is a need to have information on the synchronization status of the system. A known approach is to monitor the pointer activity. This is disadvantageous in that because of a hysteresis in the pointer processor, information derived from the pointer activity only conditionally reflects the synchronization status. In a network element (1) according to the invention which forms part of a transmission system of the above type, at least one interface unit (2, 3, 4) contains, besides an optical-to-electrical transducer (5), a synchronization-monitoring device (6) which derives a synchronization status parameter, e.g., TIE, RMSTIE, by comparing an external clock frequency (T.sub.e) with an internal clock frequency (T.sub.i). For this, the synchronization-monitoring device (6) comprises a phase-comparing device (37), a memory device (25), and an evaluating device (26).

Abstract: A mobile radio system that permits broadband radio transmission in which a mobile station (MS) can be assigned a plurality of subscriber channels (TCH) of different widths. To accomplish this, concentrators (SMX) are connected to the base stations (BS, BS') of the mobile radio system and to the mobile station (MS). These concentrators (SMX) operate in an asynchronous transfer mode to combine a plurality of subscriber channels (TCH) into one transmit channel (DL) by statistical time-division multiplexing and to separate a receive channel (UL) into the plurality of subscriber channels (TCH) by statistical time-division demultiplexing. This provides a broadband wireless link between the mobile station and the base stations which is characterized by a flexible number of subscriber channels that can have different widths.

Abstract: The invention relates to a Kerr type optical modulator and to an all-optical clock recovery circuit operating by active mode locking of a fiber loop laser including such a modulator. Operation is independent of the polarization of the signals presented to the signal input, at wavelength .lambda..sub.s. The wavelength of the clock signal delivered by the clock recovery circuit is .lambda..sub.c. The modulator comprises an even number of segments, and in a preferred embodiment four segments of polarizationmaintaining fiber, with the segments being of equivalent optical lengths, and interconnected by three splices at three locations. At the first and third splices, the neutral propagation axes of the polarization-maintaining fiber are turned through 90.degree..

Abstract: A method for interleaving data frames, a forward error correcting device and a modulator including such a device, wherein each data frame to be interleaved is divided into a plurality of words, each containing the same amount of data bytes. An overhead extension is added to the words and additionally, the resulting codewords are applied to an interleave buffer (IB) to be written in matrix-shaped structure of memory cells included in the interleave buffer (IB). This matrix-shaped structure is filled column by column in such a way that each codeword occupies another column. Data bytes are read out of the matrix-shaped structure row by row, as a result of which the data frames are interleaved.

Abstract: A prior art optical transmitter for an optical communication system having a radio system connected thereto comprises a DFB laser, an optical modulator, a signal source, and an optical filter. This optical transmitter transmits light which is not modulated by an intelligence signal. It is disadvantageous in that the optical filter and the DFB laser must be matched. An embodiment of the optical transmitter according to the invention comprises a light source (1), an optical modulator (2), and a control unit (3) which controls the light source (1) and the modulator (2) in such a way that the light emerging at the output (5) of the modulator (2) is modulated with an intelligence signal.

Abstract: With hands-free communication methods for stereophonic hands-free communication to transmit room acoustics, and with multichannel hands-free communication to reproduce different speaker locations at a conference table, the acoustical couplings between loudspeakers and microphones located in the room must especially be taken into consideration, in addition to the influence of ambient noise and the control of duplex communication situations. The n.sub.2 couplings take place in n-channel transmission systems. According to the invention, for each coupling, a coupling factor (dlm) is formed from the quotient of a short-term average value of the transmitted signal (ysam) assigned to a microphone, and the short-term average value of the received signal (xsam) assigned to a loudspeaker. With the coupling factor (dlm) weighted with the short-term average value (xsam), the transmission curve of a compander (1.1, 1.