Abstract:
A wireless apparatus includes a cellular radio interface that is adapted to perform a data exchange by way of a wireless data network, a user identity module containing information for authorization of a user for use of wireless networks, and a control unit which controls establishment and implementation of the data exchange. A second control unit is included and adapted to limit, in respect of the duration of its effect, a rejection of the user identity module expressed by the locally available wireless data networks in logging on to the wireless data network by suitable control of the first control unit in the further course of the log-on process by bypassing communicated information about the rejection.

Description:
[0001]     This U.S. utility patent application claims priority to German patent application serial no. 10 2004 043 211.2 filed Sep. 3, 2004.  
       TECHNICAL FIELD  
       [0002]     The embodiments of the present invention pertains to a wireless data interface (telemetry data interface), and more specifically, to a cellular radio interface that is adapted to perform a data exchange by way of a wireless data network, and which further controls establishment and implementation of the data exchange on the basis of items of information stored on a user identity module.  
       BACKGROUND OF THE INVENTION  
       [0003]     Wireless data devices are known in principle and are used in medical monitoring for high-risk patients or remote maintenance and diagnosis of technical equipment. Such equipment may, communicate technical or medical data to a data acquisition and evaluation center by way of a cellular radio or wireless data network, and may possibly receive instructions from the same.  
         [0004]     In that respect, portable devices are often utilized for the home monitoring of high-risk patients, such devices having a second telemetry interface for communication with an electromedical implant. Modern electromedical implants, in particular cardiac pacemakers, defibrillators and the like afford physician and patients a very high degree of security and comfort by virtue of those home-monitoring functions.  
         [0005]     In that respect the implant processes diagnosis and therapy information and transmits items of information to an external patient device by way of a telemetry interface. From there the data are passed to what is referred to as a home monitoring service center (HMSC) where they are stored and displayed for the physician. In that way the physician can be informed directly about therapy progress and the current state of health of his patients and enjoys the possibility of reacting quickly to possible changes in health.  
         [0006]     Without home monitoring the physician can obtain those items of information only in the context of an examination of the patient. In critical situations, that would result in unwanted delays in the flow of information. In addition any examination involves a considerable amount of time, both for the physician and the patient. Frequent examination has an adverse effect on the mobility and quality of life of the patient.  
         [0007]     In home monitoring, the implant information is sent via the patient device (see U.S. Pat. Nos. 6,553,262 and 5,752,976) in the background without the patient being limited in terms of leading a normal life. In other words, the patient enjoys the security of physician monitoring without the stress of frequent examinations.  
         [0008]     In the case of the technical device, continuous monitoring means that it is possible to recognize particular operating conditions so that further operation of the device can be guaranteed.  
         [0009]     As the freedom of movement of a patient is not to be unnecessarily restricted, data transmission is preferably effected by way of one of the extensively available cellular radio networks, in particular the GSM, UMTS or a CDMA network. Data transmission by way of a WLAN network can also be envisaged. The advantage of ease of connection by way of one of those wireless communication networks is rather in the foreground, but it is also possible to imagine movable items of equipment in respect of which the aspect of unrestricted mobility is also to be considered. Thus a similar device could be used in vehicles involved in goods delivery or personal transport in order, for example, to communicate to a control center various data including location, loading and technical data such as the tank filling level or the temperature of the load space. In that case the vehicle and the device are usually combined to form one unit.  
         [0010]     The development of a device of the described kind together with the cellular radio interface may be very complicated and expensive. In practice, therefore it may be made up in part from prefabricated modules, which afford given functions. That applies in particular to the cellular radio interface, which is normally embodied by a cellular telephone incorporated into the device or a prefabricated cellular radio module with full functional extent.  
         [0011]     In order to authenticate the access authorization to a wireless communication network devices equipped with a cellular radio interface are provided with a user identity module which uniquely identifies the device or its operator on the basis of items of information stored on the user identity module. When logging on to a wireless communication network the device communicates those items of information to that network which then checks the access authorization of the device by a comparison with a centrally stored copy. Identification is inter alia therefore a necessary prerequisite for use of a mobile service as it is only thereby that the connection costs incurred can be billed. Therefore it is also always involved in so-called ‘roaming’, that is to say the use of network resources and services of cellular radio network operators in other region or countries. In the case of a device which is designed to communicate by way of a GSM network the user identity module is in the form of what is referred to as a SIM card, the copy of the access authorization is stored in what is referred to as the ‘home location register’ (HLR).  
         [0012]     If an access authorization to the wireless communication network in question cannot be established, the wireless communication network communicates to the device, which is seeking to log on a request to refrain from further log-on attempts in relation to the same network in order to husband the resources thereof. As a standard procedure, cellular telephones and cellular radio modules take account of that information about a rejection and refrain from further log-on attempts in relation to the communication network in question. A further log-on attempt can be triggered only by operating the keypad of the cellular telephone or the cellular radio module. If there is no keypad or if it is inaccessible a further log-on procedure cannot be initiated at all.  
         [0013]     A log-on attempt in relation to a communication network is also rejected thereby when checking of the access authorization is not possible. That occurs, for example, when a connection could not be made to the HLR, due to a fault. Such accesses can be the subject of interference particularly when roaming because of the more complicated access to the HLR.  
         [0014]     Under some circumstances, a device may be rejected by all receivable networks and of its own accord ceases all further attempts to form a connection by way of a wireless communication network. It can then only be moved to make further log-on attempts by virtue of external intervention. As however either the user of the device is not to be bothered due to a complicated user interface or however there is no one at all present on the spot, operation of a device of the described kind in accordance with the state of the art can no longer be guaranteed.  
         [0015]     Therefore, it would be advantageous to provide a device and a method of operating such a device, which even after rejection by all receivable wireless communication networks, permits a communication of the device with the home monitoring service center if the cause of the rejection is no longer there.  
       SUMMARY OF THE INVENTION  
       [0016]     According to one aspect of an embodiment of the subject invention, a second control unit is adapted to render inoperative, or to limit in respect of the duration of its effect, a rejection of the user identity module expressed by the locally available cellular radio or wireless data networks in logging on to the cellular radio or wireless data network by suitable control of the first control unit in the further course of the log-on process by bypassing or erasing communicated information about the rejection.  
         [0017]     Another aspect of an embodiment of the subject invention is attained by a method which renders inoperative, or limits in respect of the duration of its effect, a rejection of the user identity module expressed by the locally available cellular radio or wireless data networks when logging on to the cellular radio or wireless data network by bypassing or erasing communicated messages about the rejection.  
         [0018]     In yet another aspect of an embodiment of the subject invention, the device it is portable.  
         [0019]     Still another aspect of an embodiment of the subject invention includes a device that has a second telemetry data interface by way of which it can communicate with an electromedical implant, for example a cardiac pacemaker, and permits home monitoring of a patient by evaluation and/or forwarding of the technical and medical data received from the electromedical implant, by way of the first telemetry data interface to an HMSC.  
         [0020]     In another embodiment, the communication connection is effected by way of the cellular radio interface and/or by way of a GSM, a UMTS, a CDMA or a WLAN network. In that case, the device can have any choice of interfaces with networks of the specified kinds. This may facilitate adaptation of the device to the actual conditions of the respective market and enhances the probability of a network connection in the corresponding environment.  
         [0021]     At least one of the control units of the device may be adapted to recognize unsuccessful log-on because of rejection by all cellular radio or wireless data networks available on the spot. Thereupon, the particular steps of the method of an embodiment of the subject invention can be initiated.  
         [0022]     In a further embodiment, the configuration of the first control unit may be adapted to produce a list of the locally receivable cellular radio or wireless data networks and make it available to the second control unit. In a particular variant of this embodiment, the second control unit may be adapted, after a failed log-on, to select another network from the list and to cause the first control unit to make a log-on attempt in relation to that network even if that network had already rejected a log-on in a preceding attempt. The second control unit may be adapted to cause a fresh list to be produced by the first control unit after unsuccessful log-on attempts in relation to all networks of the list.  
         [0023]     In yet another embodiment, the second control unit may include a timer or may be connected to a timer. The control unit is designed in such a way that, after a failed log-on, it allows the elapse of a predetermined period of time measured by the timer, before it initiates a further log-on attempt in relation to the same network. That husbands both the resources of the network operators and also the battery life of the device.  
         [0024]     In still another embodiment, the control units may be adapted to output and/or execute AT commands. AT commands represent a generally accepted standard, for which reason many prefabricated components and modules operate therewith; the use thereof therefore simplifies the structure of the overall system.  
         [0025]     In even another embodiment, the second control unit may include a timer or is connected to a timer. It is so designed that it defers repeated log-on attempts that are unsuccessful in relation to all available cellular radio or wireless data networks for a given time, which is measured by the timer. Once again that measure husbands both the resources of the network operators and also those of the device.  
         [0026]     The second control unit may advantageously be designed to predetermine and alter operating parameters such as, for example, the pause between two log-on attempts, the maximum number of log-on attempts and the maximum time which is used for a log-on attempt before it is broken off as being unsuccessful. The operating parameters to be adapted can be determined automatically in accordance with an algorithm as in a pseudo-random process or another process. In a particular variant of this embodiment, the second control unit is directly or indirectly connected to the cellular radio interface and so designed that the choice of the parameters can be affected and triggered from the HMSC by way of the cellular radio interface. In that way, in operation, it is still possible to effect optimizations in respect of the operating parameters, which for example allow a longer battery life or adapt the device to particular prevailing conditions of a country where it is located. A method involves firstly detecting an unsuccessful log-on by virtue of rejection by all cellular radio or wireless data networks available on the spot.  
         [0027]     In another embodiment of the methods referred to, a list of the locally receivable cellular radio or wireless data networks is produced and a sequence of the individual entries in the list is established. In a particularly variant of that method, the sequence of the list of the locally receivable cellular radio or wireless data networks is determined in accordance with the respective reception strength so that networks of a higher reception strength are preferred. That measure increases the probability of error-free data transmission if firstly a log-on attempt is affected in relation to a better receivable network and the log-on is successful.  
         [0028]     In another embodiment of the method, after a failed log-on in relation to a network, the network in the list which is next in the sequence thereof is selected and a log-on attempt is implemented in relation to that network, even if that network had already rejected a log-on in a preceding attempt.  
         [0029]     After unsuccessful log-ons, in relation to all networks in the list, a new list is produced. That takes account of changes in the availability of networks, which are caused for example by a change in location while the method is being carried out.  
         [0030]     In another embodiment of the method, after a predetermined time, a log-on attempt in relation to a network is considered to be failed and it is broken off if no positive return message has been given by the network.  
         [0031]     In still another embodiment of the method, after a failed log-on, a predetermined time is allowed to elapse before a further log-on attempt is initiated in relation to the same network. The advantage of that measure lies in husbanding of resources on both sides.  
         [0032]     In a further variant of the method, after a predetermined number of failed log-ons, further log-on attempts in relation to the same or other networks are deferred for a predetermined time. In this case also the respective resources are husbanded both on the part of the network operators and the device.  
         [0033]     The variants of the method involve establishing whether a log-on attempt in relation to one of the available networks was successful and, in the event of success, the method is then concluded. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0034]     The invention will now be described in greater detail by means of embodiments by way of example with reference to the Figures in which:  
         [0035]      FIG. 1  shows a block diagram of a device of the kind claimed in claim  1 ,  
         [0036]      FIG. 2  shows a block diagram of a device of the kind claimed in claim  1 , which is equipped with a second telemetry data interface,  
         [0037]      FIG. 3  shows a block diagram of a variant of a device of the kind claimed in claim  1 ,  
         [0038]      FIG. 4  shows an enlarged block diagram as an embodiment by way of example of a preferred variant as set forth in claims  11 ,  13  and  14 ,  
         [0039]      FIG. 5  shows a flow chart of a variant of the method according to the invention,  
         [0040]      FIG. 6  shows an expanded flow chart of a variant of the method according to the invention, and  
         [0041]      FIG. 7  shows a flow chart of a variant of the claimed method with AT commands for the individual steps. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0042]      FIG. 1  shows by way of example a block diagram of an embodiment of the subject invention in its general form. Essential component parts of the device are set out in the block diagram. An antenna  10  is connected to a cellular radio interface  20 , which may be controlled by a first control unit  30 . The control unit is connected to a SIM card  40 , which besides other items of information for operation of the cellular radio interface also includes those items of information for identification of the user and for proving the authorization of the user to use the cellular radio service. In accordance with the current embodiment of the invention there is provided a second control unit  50  connected to the control unit  30 . In the embodiment shown in  FIG. 1  other functional units  60 , which perform further functions of the device are connected to the second control unit  50  directly and to the first control unit  30  indirectly. It is also possible to envisage other configurations in which the other functional units  60  are connected directly to the first control unit  30  and/or indirectly to the second control unit  50 .  
         [0043]      FIG. 2  shows a specific case of the device illustrated in  FIG. 1 . It includes all the blocks which are contained in  FIG. 1  and which are not set forth in detail once again here. In addition, this device has a telemetry data interface  61  which, in the device shown in  FIG. 1 , could be included in the block of the other functional units (not specified in greater detail). That telemetry data interface can serve for example for communication with an electromedical implant so that the illustrated device becomes the mediator between an electromedical implant and a home monitoring service center.  
         [0044]      FIG. 3  shows an alternative embodiment of the claimed device. The antenna  10  is connected to the cellular radio interface  20 , as described hereinbefore. As a departure from the devices shown in the foregoing Figures the cellular radio interface  20  is here connected to the second control unit  50 , which in turn is connected to the first control unit  30 , the SIM card  40  and the other functional units  60 . The other functional units  60  can again include a second telemetry data interface. In this alternative embodiment the second control unit  50  is disposed centrally between the cellular radio interface  20 , the SIM card  40 , the first control unit  30  and the other functional units  60 . In accordance with the current embodiment of the invention it is designed in such a way that it can control and filter the communication between the first control unit  30  and the SIM card  40  and between the cellular radio interface  20  and the first control unit  30  respectively. In that way the first control unit  50  can erase an item of information about a rejection, communicated by that network in respect of which a log-on is attempted, before the first control unit  30  can note that information on the SIM card  40 . Alternatively the second control unit  50  could also prevent communication of the evaluated information about the rejection to the SIM card  40  by the first control unit  30 , by not passing the information on to the SIM card  40 . It is possible to envisage further variants as to the way in which the second control unit  50  nullifies the effect of a rejection by a cellular radio network or limits it in respect of its duration, by control, interruption and alteration of the flow of information between the SIM card  40 , the first control unit  50  and the cellular radio interface  20 . All those variants are to be embraced by the current embodiment of the subject invention.  
         [0045]      FIG. 4  shows a further block diagram of the embodiment of the subject invention. In comparison with the device shown in  FIG. 1 , the device shown in  FIG. 4  additionally has a timer  70  connected to the second control unit  50 . The timer  70  measures the configuratable times which are to be allowed to elapse between each step of the method of operation of the embodiment of the subject invention and appropriately signals the elapse of the predetermined times to the second control unit  50 .  
         [0046]      FIGS. 5 through 7  show flow charts by way of examples of the methods of operation of the embodiment of the subject invention. In all descriptions of flow charts, the numbers in brackets, in accordance with the corresponding method step, specify the numbering in the charts to which the details relate. That occurs wherever the step is not explicitly set out in the set.  
         [0047]      FIG. 5  shows a flow chart of an embodiment by way of example of the method of the embodiment of the subject invention. After the start ( 501 ), the first step affected is that of producing a list of networks ( 550 ) available at the respective location. In the next step a log-on attempt in relation to a selected network from the list is begun ( 560 ). Then the status of the cellular radio interface is queried ( 570 ) in order to check whether the log-on attempt was successful ( 580 ). If the log-on attempt was successful the method is concluded ( 999 ). Otherwise, a check is made to ascertain whether the list of the networks available on the spot includes still further networks in relation to which no log-on attempt has yet been made ( 600 ), since the list currently being used was produced. If the list has such networks, then the flow chart branches back to the step  560 , one of those networks is selected and further proceedings are as before. If the list does not include any further networks, then after an optional waiting pause  620 , the flow chart branches back to the step  550  and a fresh list is produced. The method is correspondingly continued until it is concluded with the success case ( 999 ).  
         [0048]      FIG. 6  shows by way of example an alternate embodiment of the method of the embodiment of the subject invention. Beginning at the start  501 , firstly the normal automated log-on process is effected ( 510 ). Thereupon the system waits for a given time ( 520 ) and then status is queried ( 530 ). If the automatic log-on process was successful ( 540 ), the method is successfully concluded ( 999 ). Otherwise a list of the networks available at the location is produced ( 550 ) and a network selected from the list ( 561 ). In relation to that network, a log-on attempt is initiated in step  562  and then the system waits for a given predeterminable time ( 564 ). A status query is then effected ( 570 ) and the result is checked ( 580 ). If the device has been successfully logged on with the selected network, the method is then concluded ( 999 ). If the contrary is the case, the list being used is checked for further untested networks on the list ( 600 ). If such networks are still present on the list, the system branches back to the step  561  and the procedure correspondingly continues. If the list does not include any further untested networks, a check is made to ascertain whether a predetermined maximum number of log-on attempts have been reached ( 610 ). That maximum number of log-on attempts can relate to the number of the total log-on attempts made or the number of log-on attempts made per network or the number of processed lists. When the maximum number is reached the log-on attempts are deferred for a predetermined time ( 620  then back to  550 ), otherwise the flow chart branches back to the step  550  directly or after a shorter pause than when the maximum number is reached. A variant of this method provides that checking of the maximum number of log-on attempts for each network is also effected individually and that network is excluded from further log-on attempts for a predetermined time when the maximum number of log-on attempts is reached. That is appropriate when the lists vary for example due to changes in location, so that they effect a changing selection of networks. After production of the list of the available networks ( 550 ), in an additional step those networks in respect of which the predetermined maximum number of log-on attempts has already been reached are deleted from the list. After the expiry of a time measured individually for each network, the networks are then restored to the produced lists again, if they are available at the location involved.  
         [0049]      FIG. 7  shows a flow chart of a similar method to that illustrated in  FIG. 6 . Here however AT commands are specified as examples in order to explain control of the first control unit  30  (in  FIGS. 1 through 4 ) of an apparatus as set forth herein. At locations where branching is involved in dependence on the result of an AT command, typical responses are “OK” in the success case and “ERROR” in the error case. Starting at  501 , the command AT+CPIN=“PIN-Code” is outputted in step  511 . “PIN-Code” means the so-called PIN code of the SIM card, which in the AT command, is between double quotes (for example: “1234”). That command causes the receiving control unit to communicate the PIN code to the SI card, which compares it to the internally stored copy. That process is not to be confused with communication of the secret user identity information, which is stored on the SIM card to the HLR. The step of checking the PIN code may involve a security mechanism, which was introduced to protect the device from use by persons other than the owner. The PIN code can therefore also usually be selected by the latter. The result of the operation of checking the PIN code which is here not necessarily selected and inputted by the user but which rather is included directly in the control sequence of the control units, consisting of AT commands, is queried in step  531  with the AT command AT+CPIN?. Input of the PIN card normally initiates an automatic log-on process in the case of cellular radio interfaces, which are designed in accordance with the state of the art. The system can wait for the complete implementation thereof by a pause (not shown in the Figure) between the steps  531  and  532 . The procedure continues with step  532  by the log-on status being queried with the AT command AT+CREG?. If the device were already successfully logged on in the automatic log-on process, the checking operation in  540  is directly followed by the end of the method ( 999 ). Otherwise the receiving control unit in step  551  is instructed by the AT command AT+COPS=? to produce and output a list of the receivable networks. In step  561  a network from the list is selected and a log-on in relation to that network is initiated at  563  by an AT command such as for example AT+COPS=4, 2,“26201”. In that respect the third command parameter determines by the five-digit network identification the respective network in relation to which the log-on is to be tried. Step  564  possibly involves waiting for a predetermined time before the log-on status is queried in step  561  with AT+CREG?. Step  564  can be omitted if the status query triggered in step  571  itself already includes a waiting time. If the device has been successfully logged on ( 580 ), the method is concluded ( 999 ). Otherwise, a check is made to ascertain whether, in the log-on procedure, a predetermined maximum time for log-on has already been exceeded ( 590 ). If no time has been exceeded in that respect, the flow chart can branch back to step  564  and the system can again wait. If however the time has been exceeded, then the log-on attempt was unsuccessful and a check is made in step  600  to ascertain whether the used list of available networks still includes entries, which are unchecked at the current time. If there are still such further networks, the flow chart goes back to step  561  and a log-on attempt is affected in relation to one of the unchecked networks. If the list does not contain any further untested networks, a check is made to ascertain whether a predetermined maximum number of log-on attempts have been reached. That maximum number of log-on attempts, as already explained in the description relating to  FIG. 6 , can relate both to the number of log-on attempts in relation to each individual network within a given period of time and also the number of lists of networks available at the location, which have been processed since the last deferment or the beginning of the log-on procedure. If the maximum number of log-on attempts has been reached, the log-on attempts are deferred by waiting ( 620 ), otherwise the flow chart will go back to step  551  after no pause at all or a shorter pause than in  620 , and continue to operate with a new list.