Abstract:
In a method for wireless exchange of device data between a control unit of a motor vehicle and a vehicle-external computing device, a mobile radio connection is established between a mobile radio module of the motor vehicle and a mobile radio cell of a radio station coupled with the computing device. The device data are transmitted via the mobile radio connection. The radio station provides a private mobile radio cell which is different from all mobile radio cells of public mobile radio networks able to reach the motor vehicle. To establish the mobile radio connection in the motor vehicle, the mobile radio module is reconfigured for registering with the private mobile radio cell by using a SIM card.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the priority of German Patent Application, Serial No. 10 2013 014 878.2, filed Sep. 6, 2013, pursuant to 35 U.S.C. 119(a)-(d), the content of which is incorporated herein by reference in its entirety as if fully set forth herein. 
     BACKGROUND OF THE INVENTION 
     The invention relates to a method for wireless exchange of device information between a control unit of a motor vehicle and a vehicle-external stationary computing device by establishing a mobile radio connection between a mobile radio module of the motor vehicle and a radio station of a mobile radio cell coupled to the computing device and transmitting the device data over the mobile radio connection. 
     The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention. 
     The ability to flexibly configure systems in motor vehicles has in conjunction with the continually falling cost of semiconductor memory led to a shift in the tasks from development to production of a motor vehicle in the following manner: While different variants of control units were initially developed for the various applications, modern control unit concepts provide a universal hardware basis, which can be flexibly configured for the particular application by using a suitable device. In this context, one differentiates between three different possibilities, namely encoding, parameterizing and flashing. With encoding, software switches are set to activate or deactivate certain parts of the application stored in the control unit or to inactive. Parameterizing includes loading of parameter lists and/or characteristic curves. Finally, with flashing of control units, either the complete application or parts thereof are loaded into the control unit and stored therein. 
     This approach significantly simplifies the provision of parts in production through logistics, because a smaller staging area is required at the assembly line and the worker needs to install a smaller number of variants. This reduces the likelihood of errors, and a control unit can be configured automatically, avoiding that workers are occupied with these tasks. 
     However, the fault-free operation of complex electronic systems requires the elimination of mistakes during the assembly process. This requirement is generally not met for manual assembly processes. In other words, there is a potential risk for installation errors. In order to still achieve the required quality targets, such processes must be protected by suitable tests. 
     This vehicle diagnosis is therefore performed in a wired configuration by using multichannel diagnostic communication. The communication with the higher-level host computer, i.e. with a central computing device for supplying the test device occurs wirelessly, for example via WLAN (Wireless Local Area Network) for the IT infrastructure of production, i.e. in particular its data network. The exchange of data on this radio connection is directed in particular to the vehicle equipment data, test programs including test parameters and the test result data for quality and statistical systems. 
     It is known in the art to establish a wireless connection to an internal vehicle module for data exchange of device data of vehicle control units. This eliminates the need for connecting a diagnostic device with a WLAN module to the motor vehicle. However, by using a radio connection, the transmission capacity disadvantageously depends on a current utilization of the radio cell and is therefore unreliable. An integration of this transmission technology in a manufacturing and/or servicing process of a motor vehicle is therefore risky. 
     It would therefore be desirable and advantageous to obviate prior art shortcomings and to provide an improved method and device for reliably exchanging wirelessly in a service facility and/or on factory premises device data between control units of motor vehicles and a vehicle-external central computing device of the service facility and/or the factory premises. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, a method for wireless exchange of device data between a control unit installed in a motor vehicle and a vehicle-external computing device includes setting up a mobile radio connection between a mobile radio module of the motor vehicle and a radio station of a mobile radio cell that is coupled with the vehicle-external computing device and has a private mobile radio cell that is different from all mobile radio cells of public mobile radio networks reaching the motor vehicle, wherein for setting up the wireless radio connection in the motor vehicle, the mobile radio module is reconfigured for registering with the private mobile radio cell by using a SIM card, and transmitting the device data via the mobile radio connection. 
     According to the invention, a private mobile radio cell is provided by the radio station with which the computing device is coupled, wherein the private mobile radio cell is different from all mobile radio cells of public mobile radio networks that can reach the motor vehicle. A mobile radio cell is the particular area that is technically served for transmission by a transmitting and receiving unit of the radio station, i.e. in which the mobile radio connection with the mobile radio module of the motor vehicle is possible. The mobile radio module may, for example, be a GSM module, a UMTS module or an LTE module or e.g. a mobile radio module that provides a plurality of the aforementioned mobile radio standards. 
     In other words, for example, a base station or radio station which is not connected to the public telephone network of a mobile radio provider, but rather to a separate data network of the central computing device, is provided on the premises where the vehicle is produced or serviced. A conventional mobile radio device, for example a Smartphone, and a conventional IMSI (International Mobile Subscriber Identity) acquired in conjunction with a mobile phone contract would therefore not allow access to this private mobile radio cell, i.e. registration with the IMSI would not be permitted. In particular, voice communication would also not be permitted in the private mobile radio cell, but only a transmission of device data from and/or for a processing unit of at least one control unit of a motor vehicle. Accordingly, the radio station is especially configured so that it can only be used to transmit device data exclusively to and from the central computing device. 
     Because just any mobile device is not allowed to communicate with the private mobile radio cell, the mobile radio module of the motor vehicle must be equipped to establish the mobile radio connection. The mobile radio module is therefore reconfigured in the motor vehicle for registering in the private mobile radio cell. In the method according to the invention, reconfiguration is performed by using a SIM card. 
     With the present invention, only a controlled number of wireless connections, which is limited by the number of reconfigured mobile radio modules located in the mobile radio cell of the motor vehicle, is advantageously established in the private mobile radio cell. The utilization of the transmission capacity of the radio station is thereby advantageously controlled so that a minimum band width can always be ensured for exchanging the device data. 
     For example, a separate SIM card may be provided for the reconfiguration, which is temporarily installed for example by a service technician during the production of the motor vehicle or when the motor vehicle undergoes service. According to an advantageous embodiment of the invention, however, the SIM card may be an embedded UICC (UICC—Universal Integrated Circuit Card) that is permanently installed in the motor vehicle. An embedded UICC is also referred to as eUICC. For example, a eUICC according to the standard ETSI TS 103 383 V12.0.0 (2013-02) may be provided. To reconfigure the mobile radio module, a new access profile is installed in the eUICC at least once for the registration in the private mobile radio cell and/or an access profile that was previously saved in the eUICC is activated. An access profile defines in a known manner during its activation in a mobile radio module the mobile radio network to which the mobile radio module establishes a wireless connection. It includes in particular the IMSI for registering in a specific mobile radio network. 
     A motor vehicle with an eUICC has the advantage that the access profile required for establishing the mobile radio connection to the private mobile radio cell may be provided in the motor vehicle as needed and/or at a later time, for example when the motor vehicle is brought to a repair shop and a control unit of the motor vehicle should be, for example, encoded, parameterized using device data or flashed by a central processing device of the repair shop for repairs or service via the mobile phone connection and/or error and/or status messages and/or measurement data should be read from the control unit for a vehicle diagnosis. 
     According to another embodiment of the invention, the mobile radio module may be reconfigured, after the exchange of the device data, for a registration in a public mobile radio network using the SIM card. In this way, the mobile radio module is later available to a user for network services, such as mobile telephony and/or an Internet data connection and/or an emergency call function, of a type the user accesses for example via a mobile phone contract for use of the public mobile radio network. The same mobile radio module is hence used twice. 
     According to another embodiment of the invention, a microcell or picocell or femtocell may be formed by the radio cell. A femtocell is a radio cell with minimal areal coverage. It is formed by a single radio station with a transmitting and receiving unit, which is used in relatively small areas, such as inside a factory or inside other individual rooms located inside buildings. In contrast to a femtocell, a radio connection in a microcell or picocell is set up with the radio station that penetrates through one or two or three walls of the building. Radio stations that provide picocells and femtocells are known in the art. 
     As discussed above, the device data are replaced especially while the motor vehicle is produced on factory premises and/or while the motor vehicle is repaired and/or serviced on the premises of a service facility. Providing a data channel in form of the mobile radio connection is here particularly advantageous in order to be able to encode and/or parameterize and/or flash the control unit in the motor vehicle in the aforedescribed manner based on the device data. While a WLAN module is installed in motor vehicles only in exceptional cases, motor vehicles are however already during production regularly equipped with a mobile radio module. Device data can advantageously be exchanged via the mobile radio connection with a variety of different motor vehicle models without additional circuit complexity. 
     Within the context of the present invention, device data are to be understood in particular as configuration data for the control unit and/or error messages and/or status messages of the control unit. The configuration data, such as encoding data for encoding, parameter data for parameterizing or program code data for flashing, are transmitted via the mobile radio connection to the control unit and stored in the control unit. Error messages and/or status messages are transmitted from the control unit to the central computing device where they are processed. The central computing device may in particular be a conventional computer system designed for performing vehicle diagnostics and/or vehicle maintenance in a service facility or a factory of a vehicle manufacturer. 
     The mobile radio module may be reconfigured or adapted to the private mobile radio cell, for example, manually by a service technician by activating a corresponding function in a configuration menu of the motor vehicle. According to another embodiment of the invention, a self-test may be initiated in the motor vehicle, and the mobile radio module is then reconfigured automatically by a control unit of the motor vehicle during the self-test. The reconfiguration is then advantageously integrated in the self-test. 
     The private mobile radio cell can be used to realize another advantage. According to another embodiment of the invention, the motor vehicle may be localized by the radio station on a factory premises or the premises of a service facility with a locating device. The motor vehicle can then be localized, for example, by radio triangulation on the premises of the service facility or the factory. To this end, several antennas may be installed on the premises at different locations, as is known from so-called “location based services”. Known localization methods are for example GSM localization by evaluating the Time-Advance-Parameters and Cell-ID for a sector-specific localization of the motor vehicle on the premises. 
     The invention is not limited to a single radio cell. According to another embodiment of the invention, at least one additional radio station coupled to the central computing device may be provided, wherein each additional radio station includes a private mobile radio cell. The mobile radio cells of all radio stations are hereby connected so as to form a private mobile radio network. This has the advantage that the mobile radio connection is forwarded between the radio stations, so that the vehicle can be moved within the area covered by the private mobile radio network, and the device data can be transmitted during this time. In addition, an improved triangulation is possible with several radio stations. 
     According to another aspect of the invention, a motor vehicle includes at least one control unit for providing a respective vehicle functionality in the motor vehicle, for example an engine controller and/or a controller for an infotainment system. The motor vehicle also includes the aforedescribed mobile radio module which is configured to set up a mobile radio connection to a radio station of a mobile radio cell in dependence of a currently active access profile of an eUICC. A mobile radio connection to the described radio station of the private mobile radio cell can hence be established with a suitable active access profile. The motor vehicle according to the invention has two modes of operation, a driving mode and a service mode. In the driving mode, the at least one control unit provides its respective vehicle functionality. The driving mode is in particular active while driving, i.e. while the user of the motor vehicle drives the motor vehicle. The service mode is active in particular during the production of the motor vehicle and/or while the motor vehicle is a service facility. In the service mode, the at least one control unit is set up for reprogramming and/or verification of the respective vehicle functionality. Reprogramming hereby refers to one or more of the aforementioned methods of encoding, parameterization, and flashing. Checking is performed in particular by reading out error messages and/or status messages and/or performing a self-test. 
     In the motor vehicle according to the invention, a configuration device is provided which is configured to activate for the driving mode in the eUICC an access profile that is predefined by a vehicle user and for the service mode a user-independent access profile for a private mobile radio cell. In this way, in the service mode, device data to be exchanged with a central computing device of the production or service facility can advantageously be transmitted via a mobile radio connection of a private mobile radio cell. Conversely, in the driving mode, the user can use the mobile radio module to make telephone calls and/or to exchange user data via the Internet. 
     The motor vehicle according to the invention is preferably configured as a motor car, especially as a passenger car. 
     According to another aspect of the invention, the invention also includes a facility for production or service or repair of the vehicle. The facility has on its premises room for at least one motor vehicle. For example, the premises may be or may include a factory hangar or a garage. At least one radio station of the system has radio coverage which is to a major part directed towards to a portion of the premises or on the entire area. A central computing device of the system is configured to generate and/or process device data of at least one control unit of the at least one motor vehicle as well as to exchange the device data with the at least one motor vehicle via the at least one radio station. The at least one radio station is in each case configured to provide a private mobile radio cell. Thus, the same advantages are attained here as with the method of the present invention. 
     The motor vehicle according to the invention together with the facility according to the invention forms a system according to the invention, with which an embodiment of the method according to the invention can be performed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which: 
         FIG. 1  shows a schematic diagram of an embodiment of the system according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the FIGURE is not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted. 
     Turning now to the drawing, and in particular to  FIG. 1 , there is shown a motor vehicle  10  in a facility  12 . The motor vehicle  10  may be in particular a motor car, such as a passenger car. The facility  12  may for example be a production plant where the motor vehicle  10  is produced, or a service facility, where the motor vehicle  10  is to be in serviced and/or repaired. 
     The motor vehicle  10  may include a mobile radio module  14 , which may, for example, be a GSM, UMTS or LTE module or a module combining these radio technologies. In the motor vehicle  10 , digital device data may be exchanged between the mobile radio module  14  one or more control units  18 ,  20  via a communication bus  16 , such as a CAN bus. The mobile radio module  14  may include an eUICC  22  embodied as a SIM card for providing one or more access profiles to public mobile radio networks that offer, for example, mobile telephone calls and/or Internet access. The mobile radio module  14  may include a configuration device  24  for programming and/or switching between access profiles of the eUICC  22 . The configuration device  24  may, for example, be a program module of a control processor of the mobile radio module  14 . The eUICC  22  may be permanently installed in the motor vehicle  10 . However, the eUICC  22  may also be provided an insertion slot in which an (unillustrated) user of the motor vehicle  10  may insert an additional SIM card, with which a public mobile communications network to be used by the mobile radio module  14  in a driving mode of the motor vehicle  10  may be defined. 
     The facility  12  may include, for example a hangar  26 , such as a production facility or a service facility. In the illustrated example, the motor vehicle  10  is parked in the hangar  26 . A radio station  28  of the facility  12  and the mobile radio module  14  may set up in a conventional manner a mobile radio connection  32  by way of mobile radio  30 ,  30 ′ in order to exchange the aforementioned device data between the mobile radio module  14  and a central computing device  34 . The transmission power of mobile radio station  28  may be so low that the radio station forms a femtocell F which extends, for example, only inside the hangar  26 . The radio waves of mobile radio  30  may form a beam cone C directed to the femtocell F. 
     The computing device  34  may include a server system  36  and a data network  38  connecting the server system  36  to the radio station  28 . The server system  36  may include one or more computers and may be configured to process device data of the control units  18 ,  20  and/or to supply device data to the control units  18 ,  20 . The server system  36  may be a server system  36  for performing at least one vehicle diagnosis in the motor vehicle  10 . 
     The femtocell F is a private mobile radio cell, i.e. the radio station  28  is in particular not connected to any packet-switched network, which may be part of a telephone network (PSTN—Public Switched Telephone Network). In particular, the radio station  28  is exclusively connected to the data network  38 . 
     The server system  36  may also be connected via the data network  36  with one or more additional (unillustrated) radio stations of the facility  12 . The server system  36  may for example be provided specifically for a production facility and/or a service facility. The server system  36  may also be connected via the data network  38  with several production facilities and/or several service facilities, in particular with one or more respective radio stations thereof. The data network may be based at least partially, for example, on the Internet Protocol (IP). 
     The facility  12  advantageously utilizes the increasingly comprehensive connectivity installed in motor vehicles which are equipped with SIM cards and a mobile radio module  14  controlled by the SIM cards. When an embedded SIM (eSIM) or eUICC  22  is installed in such a vehicle  10 , the SIM is no longer permanently assigned to the wireless service provider. Through software adaptation (commissioning) of the eUICC  22 , the provider/mobile radio provider can be freely selected without installing or changing a specific SIM. This commissioning may be performed, for example, with the configuration device  24 . Commissioning makes it possible to provide connectivity of the motor vehicle also without connecting to the public wireless network, i.e. also to the femtocell F of the radio station  28 . 
     A dedicated local mobile radio network, such as the femtocell F, enables the direct communication between the motor vehicle  10 , for example via GSM, UMTS or LTE, and a back-end system which is in the present example embodied by the computing device  34 . The access of the control units  18 ,  20  to this network enables a wireless exchange of device data between the testing technology of the computing device  34  and the vehicle  10 , for example a parameterization of the control units  18 ,  20 , reading/writing of fault memory entries, flashing the control units  18 ,  20 , transmitting navigation data to a navigation device and/or for example a SWaP. Mobile radio services may be provided for internal, production-specific issues and services which should not be accessible via non-vehicle terminals, such as Smartphones. The status of the vehicle  10  may also be read and intentionally changed. 
     Especially with the new connection services, setting up a dedicated mobile radio network with the private mobile radio cell provided as the femtocell F and with additional private mobile radio cells networked therewith is advantageous, since the control units and their services can be tested in a production environment with an existing IT backend, i.e. with the computing device  34 . Moreover, no additional hardware needs to be installed, because the eSIM can also be installed in all series-production motor vehicles for other purposes. The eSIM can therefore be pre-commissioned for the private mobile radio network of the vehicle manufacturer, i.e. may have a corresponding access profile that can be activated, if necessary, for example by the configuration device  24 , when the motor vehicle is brought, for example, to a service facility, and is located for example in the femtocell F. 
     The private mobile radio network of the vehicle manufacturer, based for example on the individual femtocell Z, also allows service applications in garages and at dealers to directly access the motor vehicle via the mobile radio connection  32  without establishing a hard-wired connection with the motor vehicle  10  for testing. This allows the customer service to communicate with the motor vehicle for diagnostic purposes without the need to establish a wired connection in the service facility. The software of the motor vehicle  10  can hence be updated without the need to occupy a bay in the repair shop for a longer duration. 
     Testing of the motor vehicle  10  with the computing device  34  may include a multi-stage procedure: initially, for example, by sending a control command from the radio station  28 , the computing device  34  may set the feature of the vehicle  10  to be tested, i.e. the control unit  18 ,  20  providing the vehicle functionality, to the state to be tested. In the next step, the measured value may be acquired, wherein measured data are transmitted from the motor vehicle  10  via the mobile radio connection  32  to the computing device  34 . Finally, the computing device  34  can evaluate the measured values as to whether they remain within or exceed the set limits. 
     The diagnostic functions frequently used in tests may be:
         a) Reading the identification of at least one control unit  18 ,  20  to determine whether the correct variant of the control unit was installed. This diagnostic service is frequently also used simultaneously to check whether a control unit  18 ,  20  can be addressed in principle by the diagnosis. It is checked whether a control unit  18 ,  20  is initially correctly powered and can be correctly addressed via the mobile radio connection  32 .   b) Reading out an error memory of a control unit  18 ,  20  via the mobile radio connection  32 , to determine whether the control unit  18 ,  20  is operating nominally. No error memory entries should be present after all startup and testing operations have been performed.   c) Reading out measured values is preferably used to read the measurement result during a test and to externally evaluate this result, for example, in the facility  12 .       

     Furthermore, self-tests may be implemented in the control units  18 ,  20 . These may either be triggered automatically, for example after “ignition on” was detected, i.e. the terminal- 15  signal. The control units  18 ,  20  can also provide self-tests which must be triggered by the vehicle diagnostics. One example therefor is the automatic engine test. In this extensive test, the engine controller performs several successive test steps so as to test the functionality of all exhaust-relevant components. The test result is stored in the form of fault memory entries. Furthermore, so-called readiness codes allow a conclusion as to whether all partial tests were performed error-free or which partial tests may have been faulty. 
     To accommodate the commissioning and testing processes of the highly networked and complex vehicle electronics within shorter production cycle times, the performance of the employed test equipment must be brought to a high level. All possibilities of the vehicle-side diagnosis of the control units are exploited by using such high-performance devices. In particular, the multiple parallelism of the diagnostic communication via a diagnostic CAN and vehicle gateway and the increasing computational requirements at run-time by the so-called ASAM-ODX data input and other data containers (for example, the variant coding of the electronic control units) require high computational power and data throughput. These data rates can be ensured in a private mobile radio cell and a private radio network. The high computing power can be provided by the central computing device  34  outside the motor vehicle  10 . 
     A local, private mobile radio network can also be set up in cooperation with a mobile radio provider of public mobile radio networks. For this purpose, a virtual private network (VPN—Virtual Private Network) may be configured within a public mobile radio network in a conventional manner. 
     Conventional motor vehicles usually have only one specific SIM card, with which either a unique identification of the user or the motor vehicle is possible for the purpose of exchanging information over a public mobile radio network. The key differences between the facility  12  and the vehicle  10  are that an embedded UICC (eUICC) is used instead of a SIM (customer or permanently installed). This eUICC is provisioned as needed for new networks (e.g. production network). This new technology provides expanded usage approaches. Independent thereof, the use of picocells/femtocells addresses the production and customer service. The required cooperation with a network operator is technically feasible (closed user group, localization, specific routing). An important difference is that telematics as well as location-based services can be created by employing such cell architectures for the production and possibly also for the customer service. 
     In summary, the example outlines an approach wherein product-independent and processor-independent, customizable mobile radio services can be provided for commissioning and/or servicing/repairing the motor vehicle by way of a manufacturer-independent eSIM and by using the eSIM a local, private mobile radio network. 
     While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit and scope of the present invention. The embodiments were chosen and described in order to explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.