Siemens Aktiengesellschaft

Infineon Technologies Ag

Paul Kunisch

Roland Krimmer

Peter Caldera

Rudi Frenzel

Joerg Hauptmann

Markus Terschluse

Hans W Rudolf

Hans-Werner Rudolf

Manfred Preitnegger

Dirk Schmuecking

Gerald Höfer

Gerald Krottendorfer

The invention relates to a line terminating device for a subscriber line which transmits and receives broadband signals via a single subscriber line, a broadband signal being composed of a broadband or narrowband audio-frequency data signal and a broadband higher-frequency data signal and the frequency bands of the voice signal and of the data signal essentially not overlapping. The line terminating device according to the invention has a digital frequency separating filter in the digital section of the line terminating device, which is arranged in the digital section of the line terminating device so that the audio-frequency voice signal is separated from the higher-frequency data signal. In particular, the line terminating device is suitable for separating an ISDN or POTS voice signal from an ADSL data signal.

Line terminator unit for a subscriber line

The invention relates to a method and a circuit for adapting the impedance in a telecommunication connection comprising a speech path and a data path having modems. Conductive properties measured by the modems are used to precisely adjust the impedance on the speech path.

Method and circuit for adapting the impedance of an analog telecommunication connection

The communications system has a transmission network for transmitting useful data and control data. Call numbers are input at a subscriber terminal. A subscriber line unit with an adjustable transmission characteristic is connected between the subscriber terminal and the transmission network. A recognition unit connected to the transmission network recognizes particular call number patterns and outputs particular control signals corresponding to call number patterns. A control unit connected between the recognition unit and the subscriber line unit sets the transmission characteristic of the subscriber line unit depending on the control signals provided by the recognition unit.

Communications systems

A method of handling telephone signals supplied by an analog telephone set and data supplied by a data terminal in a subscriber line circuit of a digital telephone switching system used at least in subregions for data transmission includes directly connecting a telephone set and a data terminal with a modem to the digital telephone switching system through a common analog subscriber line, at least one of subjecting data supplied by the data terminal to a sampling operation at a sampling rate above a sampling rate required for telephone information during analog/digital conversion and coding sampling values representing data supplied by the data terminal according to a linear characteristic during analog/digital conversion, and feeding data originating from and handled by the data terminal directly to a data transmission network. A subscriber line circuit for handling telephone signals supplied by an analog telephone set and data supplied by a data terminal is also provided.

Method for processing telephone signals supplied by an analog telephone terminal and data supplied by a data terminal

A method for optimizing the transmission properties and power loss of a high voltage part integrated in a subscriber line circuit for connecting a subscriber line wherein, during XDSL data transmission in the high voltage part, current sources which are integrated in the high voltage part and which supply current to the units present in the high voltage part for the purpose of amplifying or measuring telephone signals and/or data signals (which are situated above the frequency band provided for speech), are set, no later than when such data signals are received in the high voltage part, to current values which are higher than the current values for exclusive transmission of telephone signals situated within the voice band provided for speech, such that the data signals within the high voltage part are transmitted with a high bandwidth largely without distortions and the power loss of the high voltage part is optimized.

Method for optimizing the transmission properties and the power loss of a high-voltage part which is integrated in a subscriber connection circuit for connecting a subscriber connection line

The invention is directed to a method for recognizing, in a system having a first terminal device and a second terminal device connected to a two-wire subscriber line, an off-hook condition of the second terminal device () at the two-wire subscriber line () in a switching center () or the like, in which the off-hook condition of a first terminal device () working in a different frequency band than the second terminal device at the same two-wire subscriber line is recognized by acquiring a loop d.c. (i) and comparing it to a threshold. For reducing the consumable power to be made available in the switching center (), the invention provides that the loop d.c. (i) is compared to a second threshold that is higher than the first threshold by the minimally required current level in the operation of the first terminal device (). All off-hook conditions can thus be dependably recognized in the fundamentally same way without providing additional devices and therefore having to make additional consumable power available.

Method for recognizing an off-hook condition on a single subscriber line with two terminal devices

In a circuit arrangement for recognizing connection requests at an analog subscriber line in which a number of subscriber terminal devices such as an analog telephone and an MSFM modem, are connected in parallel, set up and clear down connections are enabled independently of one another. For this purpose, a first threshold valve and a second threshold value are defined for the loop current in the subscriber line. A connection request can be respectively initiated by one of the subscriber terminal devices by means of closing its cradle switch. When the cradle switch of this first device is thus closed, the loop current exceeds the first threshold value, and when the cradle switch of a further device for initiating a connection request is also closed, the loop current exceeds the correspondingly defined second (higher) threshold value. As a result of these threshold value transgressions, the connection requests can be recognized and processed independently of one another.

Method and telecommunications center for recognizing connection requests at a subscriber line

A method for transmitting data signals on analog subscriber lines wherein bilateral data transmission between subscriber terminal equipment and exchange is intended to occur, with relative ease and with low outlay, even during speech signal transmission. A signal, preferably the charge pulse signal, that is already generated at least in the exchange for some other use is employed as a carrier signal wherein, accordingly, it is possible to exploit an already existing infrastructure.

Method for transmitting data signals on analog subscriber lines

An analog telephone subscriber terminal apparatus with means for realizing additional functions is provided. In the on-hook state of the subscriber terminal apparatus, and outside of the idle operating state of the subscriber terminal apparatus, a current supply device that draws current from the subscriber line and is integrated into the terminal apparatus is switched effective for the duration of the reception of data containing the additional functions. The current supply device provides the supply current to the means for realizing the additional functions, but is limited to such an extent that the increased subscriber line loop current that then flows is not indicated as a loop closure.

Analog telephone subscriber terminal apparatus

An interface circuit with integrated test functions relating to the subscriber line, with a test circuit realized in the simplest case by an ohmic resistance, and comprising a relay circuit having two changeover contacts by means of which in one switching position the leads of the subscriber line are connected with the interface circuit, and in the other switching position the subscriber line is disconnected and the test circuit is connected to the interface circuit.

Growing community of inventors

Puchheim, Germany

Paul Kunisch