Abstract: The present invention relates to a motor vehicle that is equipped with an electrical door closing mechanism, a radio-based signal receiver and a control unit, wherein the door closing mechanism can be actuated after receiving and verifying an access authorization code by electrical signals that are generated by a control unit. The motor vehicle possesses an electrical charging apparatus accessible from the outside so that a signal generator that is provided to generate the access code can be charged from the electrical system of the motor vehicle in the event of an insufficient charge. Furthermore, the invention describes a method for charging a signal generator that can be executed using the device according to the invention.

Abstract: An apparatus for a vehicle key, an apparatus for a vehicle control system, and an apparatus for a mobile device. The apparatus includes a first interface to communicate with a vehicle control system and a second interface to communicate via a radio connection. The apparatus also includes a control module to receive proximity information from the vehicle control system via the first interface and to establish a radio connection via the second interface if the proximity information indicates spatial proximity of the vehicle key to the vehicle control system.

Abstract: A method to determine a position of a portable apparatus relative to a vehicle including generating a magnetic field by the vehicle, detecting the magnetic field by a magnetic field sensor of the portable apparatus, and evaluating the magnetic field to determine the position of the portable apparatus relative to the vehicle.

Abstract: A method for checking an authorization of a mobile communication device for operating a vehicle engine of a vehicle which includes determining a position of a mobile communication device. The position of the mobile communication device is inside or outside the vehicle. The method also includes receiving a digital key value from the mobile communication device and checking the authorization of the mobile communication device for operating the vehicle engine, based on the position of the mobile communication device and based on the digital key value.

Abstract: The present invention relates to a motor vehicle that is equipped with an electrical door closing mechanism, a radio-based signal receiver and a control unit, wherein the door closing mechanism can be actuated after receiving and verifying an access authorization code by electrical signals that are generated by a control unit. The motor vehicle possesses an electrical charging apparatus accessible from the outside so that a signal generator that is provided to generate the access code can be charged from the electrical system of the motor vehicle in the event of an insufficient charge. Furthermore, the invention describes a method for charging a signal generator that can be executed using the device according to the invention.

Abstract: An apparatus for a vehicle key, an apparatus for a vehicle control system, and an apparatus for a mobile device. The apparatus includes a first interface to communicate with a vehicle control system and a second interface to communicate via a radio connection. The apparatus also includes a control module to receive proximity information from the vehicle control system via the first interface and to establish a radio connection via the second interface if the proximity information indicates spatial proximity of the vehicle key to the vehicle control system.

Abstract: A method for checking an authorization of a mobile communication device for operating a vehicle engine of a vehicle which includes determining a position of a mobile communication device. The position of the mobile communication device is inside or outside the vehicle. The method also includes receiving a digital key value from the mobile communication device and checking the authorization of the mobile communication device for operating the vehicle engine, based on the position of the mobile communication device and based on the digital key value.

Abstract: A method to determine a position of a portable apparatus relative to a vehicle including generating a magnetic field by the vehicle, detecting the magnetic field by a magnetic field sensor of the portable apparatus, and evaluating the magnetic field to determine the position of the portable apparatus relative to the vehicle.

Abstract: The present invention relates to a method and a suitable apparatus for determining the state of a rechargeable battery and for checking contact resistances in a battery system. According to the invention, an impedance curve is determined using signals at different frequencies and a value for an area, which results from the impedance curve, is then calculated from a predetermined threshold value and an x axis. The value for the area is a measure of the ageing of the battery. A control signal is generated on the basis thereof. In one preferred embodiment, said control signal is used to drive a signaling apparatus and thus to present the state of the battery to a user. The present invention can be used, for example, in motor vehicles that are electrically driven.