Abstract: The invention relates to a function display (1) for selectively displaying several symbols representing one switching function, respectively, and/or at least two switching states, respectively, comprising: a light guide stack which, given an attachment of the function display (1) as intended, forms a display surface (8) facing towards the observer (B); wherein the light guide stack is formed from at least two transparent or translucent, planar light guides (2, 3) arranged in an overlaid manner in a stacking direction, which are arranged so as to be spaced apart by a transparent or translucent layer consisting of a material that is optically thinner compared to the adjacent light guides (2, 3), preferably an air gap (14), so that the light guides (2, 3) each have a main surface (H) facing towards the observer (B) and a main surface (H?) facing away from the observer (B), and, in at least one light guide (2), the main surface (H?) facing away from the observer (B) faces towards a light guide (3) which is most c

Abstract: A method operates a mobile device in a railway system with at least one optical waveguide which is laid next to at least one railway track and into which light pulses are fed. The optical waveguide is used as a distributed acoustic sensor and detects scattered-back light. In order to be able to identify reliably such a mobile device in a comparatively easy way, the mobile device is provided with a sound generator which can be adjusted with respect to its frequency spectrum in a way which designates the mobile device. The sound generator is adjusted with respect to its frequency spectrum in a way which designates the mobile device by assigning a frequency selection to the mobile device. An identification number signal of the mobile device is acquired by detecting the scattered-back light from the detected frequency selection. A railway system having such a mobile device is also taught.

Abstract: A method operates a mobile device in a railway system with at least one optical waveguide which is laid next to at least one railway track and into which light pulses are fed. The optical waveguide is used as a distributed acoustic sensor and detects scattered-back light. In order to be able to identify reliably such a mobile device in a comparatively easy way, the mobile device is provided with a sound generator which can be adjusted with respect to its frequency spectrum in a way which designates the mobile device. The sound generator is adjusted with respect to its frequency spectrum in a way which designates the mobile device by assigning a frequency selection to the mobile device. An identification number signal of the mobile device is acquired by detecting the scattered-back light from the detected frequency selection. A railway system having such a mobile device is also taught.

Abstract: Apparatus and method for generating a traffic encryption key includes generating a traffic encryption key for encrypting data transmitted as part of a service, the traffic encryption key having a validity equal to a traffic encryption key validity time period; checking whether a period for the service is longer than the traffic encryption key validity time period; and if the period of the service is longer than the traffic encryption key validity time period, ascertaining a residual period which indicates by what period the service is longer than the traffic encryption key validity time period of the traffic encryption key; generating a residual traffic encryption key which is used for encrypting data transmitted as part of a service; ascertaining a residual traffic encryption key validity time period which indicates for how long the residual traffic encryption key is valid; and associating the residual traffic encryption key validity time period with the residual traffic encryption key.

Abstract: A communication device including a communication connection establishing circuit configured to establish an ad hoc network communication connection between the communication device, a second communication device and a third communication device, a generating circuit configured to generate encryption parameters to be used by the second communication device and the third communication device for encrypting and decrypting data transmitted between the second communication device and the third communication device via the communication connection when the first communication device has left the communication connection, a signaling circuit configured to signal the encryption parameters to the second communication device and the third communication device, and a disconnection circuit configured to remove the communication device from the communication connection.

Abstract: In an embodiment of the invention, a communication terminal device, which may include a message generation circuit configured to generate an information inquiry message which specifies that another communication terminal device should transmit information about performance features of units in the physical layer or the data link layer of the other communication terminal device to that communication terminal device, a transmitting circuit configured to transmit the information inquiry message, a receiving circuit configured to receive an information message with the information from the other communication device terminal, and a selection circuit which is configured to use the information to select units in the physical layer or the data link layer of the communication terminal which should be used to set up a communication link to the other communication terminal device.

Abstract: An apparatus and method of grouping and assigning a plurality of random access sequences, including assigning each random access sequence to one or a plurality of user equipments, to a plurality of users, type of users or types of communication connection.

Abstract: A method is provided for handover of a communication of a mobile communication device between a first radio access network and a second radio access network. The method comprises storing, by at least one of the communication device and an element of the first radio access network, a context of the communication device in the first radio access network, the context being useable to transfer the communication back to the first radio access network after a transferring to the second radio access network; and transferring the communication to the second radio access network.

Abstract: Apparatus and method for generating a traffic encryption key includes generating a traffic encryption key for encrypting data transmitted as part of a service, the traffic encryption key having a validity equal to a traffic encryption key validity time period; checking whether a period for the service is longer than the traffic encryption key validity time period; and if the period of the service is longer than the traffic encryption key validity time period, ascertaining a residual period which indicates by what period the service is longer than the traffic encryption key validity time period of the traffic encryption key; generating a residual traffic encryption key which is used for encrypting data transmitted as part of a service; ascertaining a residual traffic encryption key validity time period which indicates for how long the residual traffic encryption key is valid; and associating the residual traffic encryption key validity time period with the residual traffic encryption key.

Abstract: A radio communication arrangement including a plurality of transceivers and a distance measurement managing circuit. The distance measurement managing circuit is situated in a communication layer higher than the physical layer, is coupled with the plurality of transceivers, and controls the plurality of transceivers for measuring the distances of the respective plurality of transceivers to a specified position. The distance measurement managing circuit also receives and processes distance measurement values determined by the plurality of transceivers.

Abstract: A communication device including a communication connection establishing circuit configured to establish an ad hoc network communication connection between the communication device, a second communication device and a third communication device, a generating circuit configured to generate encryption parameters to be used by the second communication device and the third communication device for encrypting and decrypting data transmitted between the second communication device and the third communication device via the communication connection when the first communication device has left the communication connection, a signaling circuit configured to signal the encryption parameters to the second communication device and the third communication device, and a disconnection circuit configured to remove the communication device from the communication connection.

Abstract: A radio communication arrangement including a plurality of transceivers and a distance measurement managing circuit. The distance measurement managing circuit is situated in a communication layer higher than the physical layer, is coupled with the plurality of transceivers, and controls the plurality of transceivers for measuring the distances of the respective plurality of transceivers to a specified position. The distance measurement managing circuit also receives and processes distance measurement values determined by the plurality of transceivers.

Abstract: An apparatus and method of grouping and assigning a plurality of random access sequences, including assigning each random access sequence to one or a plurality of user equipments, to a plurality of users, type of users or types of communication connection.

Abstract: In an embodiment of the invention, a communication terminal device, which may include a message generation circuit configured to generate an information inquiry message which specifies that another communication terminal device should transmit information about performance features of units in the physical layer or the data link layer of the other communication terminal device to that communication terminal device, a transmitting circuit configured to transmit the information inquiry message, a receiving circuit configured to receive an information message with the information from the other communication device terminal, and a selection circuit which is configured to use the information to select units in the physical layer or the data link layer of the communication terminal which should be used to set up a communication link to the other communication terminal device.

Abstract: A method is provided for handover of a communication of a mobile communication device between a first radio access network and a second radio access network. The method comprises storing, by at least one of the communication device and an element of the first radio access network, a context of the communication device in the first radio access network, the context being useable to transfer the communication back to the first radio access network after a transferring to the second radio access network; and transferring the communication to the second radio access network.

Abstract: System information data transfer within a mobile telecommunication system to ensure that a piece of user equipment always has the most up to date information. Data is sent to the user equipment and includes information indicating a time of change of the active system information. The user equipment can use the time of change information to verify whether the system information it has stored is the latest version of the system information.

Abstract: At least one received broadcast capability parameter from at least one communication terminal participating in a communication session is used to decide whether data within the context of the communication session are to be transmitted to the communication terminal using a broadcast communication network or using a cellular mobile radio communication network.

Abstract: Server of a communication system having a broadcast communication network, a communication service server and a storage device, the server providing a plurality of media streams which can be transmitted in a service area of the broadcast communication network by the broadcast communication network. The server includes a determination device that interrogates parameter values from a storage device for each client situated in the service area, and receives data which are transmitted by the broadcast communication network, wherein the parameter values are used to determine which of the media streams are intended to be communicated to the respective client, and determines based on the parameter values which of the media streams are intended to be transmitted by the broadcast communication network in the service area. The server also includes a controller that controls the broadcast communication network such that the network transmits the media streams which are intended to be transmitted.