Abstract: Disclosed is a distance measuring system for measuring distance of a first transceiver from second transceivers, comprising the first transceiver having a first time zone, a second transceiver having a second time zone, and a control unit having a control-unit time zone. The second transceiver ascertains a time-zone relationship between the second transceiver and the first transceiver, and transmits the time-zone relationship to the control unit. The control unit receives the time-zone relationship, and ascertains, using the received time-zone relationship, a time-zone relationship between the control-unit time zone and the first transceiver. The first transceiver transmits at a defined instant in time or for a defined time period of the first time zone a distance measurement command to the second transceiver. The first transceiver transmits a measurement signal at a further defined instant in time, and the second transceiver switches from an inactive into an active receiving or measuring state.

Abstract: A method and apparatus for determining a propagation delay and/or a distance between a plurality of transceivers, in particular between transceivers outside and/or as part of a motor vehicle, wherein the transceivers are each designed: to generate identical codes in a plurality of these transceivers, using a calculation method known to them, from at least one starting value transmitted, in particular, from one of the transceivers to the further transceivers, to transmit one or more messages from at least one of the transceivers to one or more further ones of the transceivers, which messages each contain at least one of the codes, to determine at least one propagation delay and/or at least one distance between at least two of the transceivers, in particular from the propagation delay and/or transmission times of the one or more messages.

Abstract: The invention relates to a method for verifying a prescribed maximum physical distance (MAX) of a radio key (11) in relation to a motor vehicle (10), wherein a control apparatus (26) uses a radio device (21) of the motor vehicle (10) to transmit at least one electromagnetic radio signal to the radio key (11) and subsequently receives a respective electromagnetic response signal and, for each radio signal, takes the radio signal and the associated response signal as a basis in each case for using a signal propagation delay measurement to ascertain a respective signal propagation delay and checks whether the signal propagation delay fails to satisfy a predetermined propagation delay criterion (27), and signals a transgression above the propagation delay (28) when the propagation delay criterion (27) is not satisfied.

Abstract: A method and apparatus for determining a propagation delay and/or a distance between a plurality of transceivers, in particular between transceivers outside and/or as part of a motor vehicle, wherein the transceivers are each designed: to generate identical codes in a plurality of these transceivers, using a calculation method known to them, from at least one starting value transmitted, in particular, from one of the transceivers to the further transceivers, to transmit one or more messages from at least one of the transceivers to one or more further ones of the transceivers, which messages each contain at least one of the codes, to determine at least one propagation delay and/or at least one distance between at least two of the transceivers, in particular from the propagation delay and/or transmission times of the one or more messages.

Abstract: The invention relates to a method for verifying a prescribed maximum physical distance (MAX) of a radio key (11) in relation to a motor vehicle (10), wherein a control apparatus (26) uses a radio device (21) of the motor vehicle (10) to transmit at least one electromagnetic radio signal to the radio key (11) and subsequently receives a respective electromagnetic response signal and, for each radio signal, takes the radio signal and the associated response signal as a basis in each case for using a signal propagation delay measurement to ascertain a respective signal propagation delay and checks whether the signal propagation delay fails to satisfy a predetermined propagation delay criterion (27), and signals a transgression above the propagation delay (28) when the propagation delay criterion (27) is not satisfied.

Abstract: A method for access or starting verification for a vehicle using a mobile identification encoder and at least two antennas located in or on the vehicle at different locations includes: the antennas emitting electromagnetic signals at alterable times, wherein the electromagnetic signals are emitted in transmission blocks having alterable specific properties and wherein a plurality of transmission blocks are strung together to form a communication message in which each transmission block adopts an alterable position in time, the identification encoder receiving the electromagnetic signals emitted by the antennas and processing them to generate a response signal, and altering at least one of the times at which the individual antennas are actuated, the specific properties of the individual transmission blocks, and the position of the individual transmission blocks in time in the communication message in accordance with a cryptographical method.

Abstract: A method for access or starting verification for a vehicle using a mobile identification encoder and at least two antennas located in or on the vehicle at different locations includes: the antennas emitting electromagnetic signals at alterable times, wherein the electromagnetic signals are emitted in transmission blocks having alterable specific properties and wherein a plurality of transmission blocks are strung together to form a communication message in which each transmission block adopts an alterable position in time, the identification encoder receiving the electromagnetic signals emitted by the antennas and processing them to generate a response signal, and altering at least one of the times at which the individual antennas are actuated, the specific properties of the individual transmission blocks, and the position of the individual transmission blocks in time in the communication message in accordance with a cryptographical method.

Abstract: A system and a method for data communication with a vehicle control device include a flash adapter which is inserted with a vehicle key into an ignition lock of a vehicle. Upon insertion into the ignition lock, the vehicle key is authenticated. Subsequently, a comparison between the control device data stored in the key and the vehicle can be triggered by using the flash adapter.

Abstract: A passive motor vehicle access system has at least one handle on the vehicle and at least one capacitive sensor situated in the vicinity of the handle which triggers a data identification interrogation of a data carrier in the user's possession, if the handle is actuated. A method comprises: determination of the number of cases of negative data identification that have already been carried out during a pre-determined time period; comparison of the determined number of negative identification cases with a pre-determined threshold value; and additional data identification interrogation, if the number of negative data identification cases is less than the pre-determined threshold value, or transmission of a new referencing command signal to the capacitive sensor or sensors in order to obtain a new reference for the latter, if the number of negative data identification cases is equal to the pre-determined threshold value.

Abstract: A system and a method for data communication with a vehicle control device include a flash adapter which is inserted with a vehicle key into an ignition lock of a vehicle. Upon insertion into the ignition lock, the vehicle key is authenticated. Subsequently, a comparison between the control device data stored in the key and the vehicle can be triggered by using the flash adapter.

Abstract: A method and a system for exchanging data between at least one vehicle-mounted control device and a portable hand-held device, for example in the form of a key in which software for transmission to the at least one vehicle-mounted control device is stored.