Abstract:
A method for establishing a wireless connection between a mobile communication device and a communication module ( 14 ) of a vehicle ( 10 ) with an identifier ( 17 ) is disclosed. According to the method, access rights, namely links between vehicle identifiers ( 17 ) and user identifiers, as well as data required for establishing the wireless connection, are stored in a database server ( 16 ) outside of the mobile communication device. A control unit ( 11, 12 ) for carrying out the method is also disclosed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the National Stage of International Application No. PCT/EP2015/001047, filed on 22 May 2015, which claims priority to and all advantages of German Patent Application No. 10 2014 010 752.3, filed on 21 Jul. 2014, the content of which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention generally relates to a method for establishing a wireless connection and, more specifically, to a method for establishing a wireless connection between a mobile communication device and a communication module of a vehicle with an identifier, and to a control unit for a vehicle. 
       BACKGROUND OF THE INVENTION 
       [0003]    Data present in a vehicle are intended to be retrievable by a user outside the vehicle. A remote control of vehicle functions by a user outside the vehicle is preferably also intended to be possible. The user has a mobile communication device available for this purpose, for example a Smartphone or a different mobile telephone. The mobile communication device communicates wirelessly with a communication module in the vehicle. The latter serves as an interface to control units in the vehicle and is part of a control unit or is connected to a control unit. The control unit is, in particular, a braking control unit which is connected to the vehicle&#39;s own data bus system (CAN bus or other) and with which functions in the vehicle are controllable. The control unit receives data from allocated sensors or via the vehicle&#39;s own data bus. 
         [0004]    Only selected and uniquely identifiable users are intended to be able to connect via the mobile communication device to the communication module of the vehicle. An authentication is required. This is possible, for example, in that the communication module of the vehicle operates as an access point (server) for a local radio network (WLAN, IEEE-802.11 standard). The user can dial in to the local radio network with a WLAN-enabled mobile telephone provided that the user knows the data required for establishing the connection or has even already stored the data in his mobile telephone. 
         [0005]    At a depot with a plurality of vehicles, vehicles are used progressively by different users so that the data required for establishing the radio connection remain in different mobile telephones. A user can progressively connect with his mobile telephone to the communication modules of different vehicles. Mistakes can easily occur in relation to the currently existing connection to a specific vehicle. Substantial damage can thus occur in connection with the remote control of functions of the vehicle. 
         [0006]    Access to the communication module of a specific vehicle is intended to be configurable as easily as possible. It may thus be appropriate to allow specific connections only at specific times of the day or on specific weekdays. A unique allocation between the vehicle on the one hand and the mobile communication device on the other hand which is transparent to the user is also intended to be provided. Finally, the establishment of the connection must be as simple as possible for the user. 
       SUMMARY OF THE INVENTION 
       [0007]    The method according to the invention comprises:
       a) access rights, i.e. links between vehicle identifiers and user identifiers, and also data for establishing the wireless connection are stored on a (data) server outside the mobile communication device,   b) the identifier of the vehicle is recorded with the mobile communication device,   c) the user identifier is present in the mobile communication device,   d) the mobile communication device transmits the recorded vehicle identifier and the user identifier to the server,   e) the server checks whether access rights exist for the forwarded combination of identifiers,   f) if access rights exist, the server transmits the data required for establishing the wireless connection to the mobile communication unit, and   g) the mobile communication device establishes a wireless connection to the communication module of the vehicle with the data forwarded from the server.       
 
         [0015]    The mobile communication device has the characteristics required to carry out the method, i.e. hardware and software for recording the vehicle identifier, hardware and software for establishing a connection to the server and hardware and software for establishing a wireless connection to the communication module of the vehicle. 
         [0016]    Combinations of vehicle identifiers with user identifiers and the access data for the communication with the vehicle are stored in the server as datasets. If the requested combination is not stored, no connection is established between the mobile communication device and the communication module of the vehicle. In addition to the aforementioned data, further details, such as restrictions relating to the vehicle identifier and/or the user identifier, can be stored in the server. It may thus be appropriate to allow connections for specific users and/or specific vehicles only at specific times, such as specific users only during normal working hours and specific vehicles not on Sundays and public holidays. 
         [0017]    The server can be configured by an operator of a vehicle fleet. Vehicle identifiers, user identifiers, connection data and restrictions can thus be centrally managed, adapted and updated. 
         [0018]    In certain embodiments, a number plate, a chassis number, an optical pattern, data transmittable via RFID (Radio Frequency Identification) or data transmittable via NFC (Near Field Communication) are used as the vehicle identifier. The number plate is preferably read by the mobile communication device. The inscription on the number plate is also referred to colloquially as the vehicle registration number. Here, the vehicle identifier may actually contain different data or may be of a different type. What is important is that the identifier enables a unique allocation to the vehicle. A QR code as an optical pattern or a radio tag with data transmittable via RFID can also be used for this purpose. A vehicle identifier can also be stored in the communication model and can be readable via NFC. 
         [0019]    In these or other embodiments, the mobile communication device reads the data representing the vehicle identifier as an optical pattern or via a radio link. The optical pattern is, for example, recordable by a camera allocated to the mobile communication device and is convertible into suitable data by software provided for this purpose. 
         [0020]    Typically, the user identifier comprises data which are stored in the mobile communication device or are input by the user into the mobile communication device. This may involve a device ID, a SIM card number or a number stored in a file of the communication device. The user can also type an identifier into the mobile communication device in an emergency. 
         [0021]    In certain embodiments, the mobile communication device forwards the two identifiers (vehicle identifier and user identifier) via a mobile radio link or via a WLAN to an interface connected to the server. The server is preferably addressable via the Internet or via a different network. The interface connected to the server enables wireless access to the server via a mobile radio link or via a WLAN. The server and interface may be located spatially far apart from one another. 
         [0022]    In these or other embodiments, the wireless connection from the mobile communication device to the communication module of the vehicle is a connection via a WLAN or Bluetooth. A different digital radio technology with the facility for an encrypted connection can also be used. The communication module is intended, in particular, to be addressable by the mobile communication device as an access point or in a similar function. 
         [0023]    Generally, a mobile telephone with a WLAN function and/or Bluetooth function is used as the mobile communication device. The mobile telephone is preferably a Smartphone with an app as software for recording the vehicle identifier, establishing the connections, displaying vehicle information and/or for the remote control of vehicle functions. The mobile telephone preferably has a camera with which the vehicle identifier is readable. The software reads the vehicle identifier from the recorded camera image and from it generates the data that are to be forwarded to the server, the data furthermore containing information relating to the user identifier. 
         [0024]    According to certain embodiments, the vehicle emits a visually or audibly perceptible signal, e.g. a light-flashing code or a horn signal, after establishing the wireless connection between the mobile communication device and the communication module. A signal confirming the existing connection can also be displayed on a screen of the mobile communication device, additionally or alternatively to a sound signal. 
         [0025]    The invention also provides a control unit for a vehicle, in particular for an electronic braking system, with a communication module and for use in a method according to the invention. The communication module forms part of the control unit or is connected to the control unit at least via a data line. The control unit is preferably connected to the vehicle&#39;s own data bus system (CAN bus) and can thus communicate with other control units in the vehicle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The invention is described in greater detail below with reference to the accompanying FIGURE, in which: 
           [0027]      FIG. 1  shows various aspects associated with implementing a method in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    As shown in  FIG. 1 , a vehicle  10  is equipped with an electronic braking system and has a braking control unit  11  and an engine control unit  12  which is connected to a CAN bus  13 . Further control units may also be provided. Sensors are allocated to the control units, the data from the sensors being processed by the control units. A communication module  14  with which a communication is possible via a radio link, e.g. via a WLAN, is allocated here to the braking control unit  11 . A wireless contact to the braking control unit  11  and/or to the CAN bus  13  is possible by means of the communication module  14 . The technology for the linking of CAN networks to WLAN networks is known. Interfaces are available for this purpose. 
         [0029]    In the present example embodiment, the vehicle  10  is a motor vehicle. However, it may also be a trailer vehicle, in the simple case also only with one control unit and no CAN bus. 
         [0030]    A user of the vehicle  10  would like to retrieve information from the vehicle and/or control functions of the vehicle  10  via his Smartphone  15 . A connection with a unique allocation between the vehicle  10  and the Smartphone  15  is required, taking account of possible access right restrictions. 
         [0031]    Datasets containing permissible combinations of vehicles  10  with Smartphones  15  are stored on a database server  16 , here using a vehicle identifier  17  (number plate) on the one hand and a device number of the Smartphone  15  on the other hand. Alternatively or additionally, a SIM card number of the Smartphone  15  may form part of the dataset, and, if necessary, further identifying details. Finally, the datasets may also contain restrictions that are additionally to be taken into account, e.g. relating to the permissibly retrievable information or permissibly executable control commands and/or restrictions relating to the times of day and weekdays. 
         [0032]    Datasets may also be provided in which, on the one hand, the vehicle identifier  17  and, on the other hand, a device-independent key (a number or password) are stored. In addition, the connection data which are valid for each communication module  14  and which are required for establishing a connection are stored on the database server. 
         [0033]    The Smartphone  15  may be equipped with a camera (not shown) and have a WLAN function. If the user wishes to retrieve information from the vehicle  10  and/or remotely control functions with his Smartphone  15 , the following authentication procedure must be performed: 
         [0034]    Software in the form of an app is installed on the Smartphone  15  to guide the user through the authentication procedure and carry out the steps automatically, insofar as this is possible. First, the software prompts the user to record the vehicle identifier  17  with the camera of the Smartphone  15  (step I.). The read identifier is converted by the software into a character string and is forwarded together with the device number of the Smartphone  15  via a mobile radio link (step II.) to a transceiver station  18  and from there via the Internet (number  19 ) to the server  16 . The forwarded dataset is matched with the existing data in the server  16 . If the connection is permitted, the server  16  transmits its response (step III.) back to the Smartphone  15 . The response of the server  16  contains all data necessary for establishing a WLAN connection, the WLAN network name (SSID), encryption type and password. With the data, the software of the Smartphone  15  automatically establishes the WLAN connection (step IV.) to the communication module  14 . The latter performs the function of an access point (server) in the WLAN network. The WLAN connection is then set up, the retrieval of information from the vehicle  10  and, if necessary, the remote control of functions are possible. 
         [0035]    To confirm the successfully established WLAN connection to the vehicle, the latter can emit visually or audibly perceptible signals. In the present case, flashing lights  20 ,  21  are briefly activated. Furthermore, a textual confirmation, for example a reproduction  23  of the vehicle identifier  17 , appears on a screen  22  of the Smartphone  15 . 
         [0036]    Instead of a WLAN connection, a different radio technology can also be used, such as Bluetooth, or a different technology which enables an, in particular, encrypted connection. 
         [0037]    With the method according to the invention, the user can establish a secure and unique connection to the control unit of his vehicle in a simple manner with his Smartphone. Only an additional connection to a database server on the Internet is required for authentication and for forwarding the connection data. This additional connection is established here via a mobile radio link (GSM, UMTS, LTE, etc.). However, a different connection type, e.g. via a WLAN to a WLAN router in the vicinity, is also possible.