Positioning system and method

[0001] The present invention relates to a positioning system which uses the Global Positioning System (GPS) and a mobile communications network (PLMN), according to the introductory section of the method claim 1, and a positioning method which uses GPS and a mobile communications network (PLMN), according to claim 17.

[0002] From EP publication 950598 A1 (Dent Bahn AG), a compact device is known, which comprises a CPU, GPS receiver, GSM module, a combined GPS/GSM antenna, a three-dimensional coordinate-measuring device, user interface and chargeable battery. The parts of the receiver are fit into one casing, and the device is designed to transmit the produced position data, using the GPS receiver, through the GSM network to the customer service center. The device can thus be used to track and monitor moving subjects. The disadvantages of the device are that it only transmits the position data to a previously selected, immobile service center, and that the device cannot be activated into the transmission mode by an outsider.

[0003] From DE publication 19640068 A (Alcatel Alsthom cie Gen Electricite), a destination-locating device is already known, which is intended for use, for example, in GPS, GSM and NAV navigation, for determining the actual position of a vehicle. In this device, the valuation unit determines the direction towards the destination. Entered data, such as a phone number, is used to individualize the destination. These are interpreted by a comparison unit in order to obtain the coordinates of the destination, which are then compared with the actual position, in order to display the direction on a monitor or announce it on a loudspeaker. The device is in communication with a GSM communications system in order to procure additional services.

[0004] From U.S. Pat. Nos. 5,461,365 (Dan Schlager et al.), 5,650,770 (Dan Schlager et al.) and 5,963,130 (Zoltar Satellite Alarm Systems, Inc.), a wireless system is already known, which is used for monitoring certain remote mobile stations from a base station and for activating alarms when the selected parameter values have been exceeded, for example, when the set distance between a remote station and the base station is exceeded. A remote station, according to U.S. Pat. Nos. 5,650,770 and 5,963,130, can include equipment for receiving position data from satellites and for intercession via radio channels from the remote station to the base station. The problem with these kinds of alarm and tracking systems is that they do not have the encompassing range that mobile communications networks, like PLMN's, have, and the radius of effect of these systems is limited to the range of the base station's antenna which radiates 360. Since this is a question of an alarm and tracking system, this also poses an essential risk, in the event that an alarm is given to a remote station that has, for some reason, drifted beyond the antenna range of the base station.

[0005] The primary object of the present invention is to provide a new kind of way to determine the position of a desired subject mobile station(s) of a mobile communications network, by which the position(s) of the subject station(s) is conveyed to the inquiring mobile station of the mobile communications network. A secondary object of the present invention is to eliminate, or at least reduce, the weaknesses and disadvantages already associated with conventional means of position determination and tracking remote stations.

[0006] These objects are accomplished by means of the positioning system and method mentioned in the beginning, which uses GPS and a mobile communications network (PLMN), the specific characteristics of which are presented in the accompanying claims.

[0007] The invention is thus based on a new and inventive idea, that data on the position of one subject mobile station, which is a combination, for example, of a GSM communications system and a GPS receiver, and which has the capacity to determine its own position using GPS, is transmitted to the inquiring mobile station through a mobile communications network using a data transmission connection which is supported by the mobile communications network, advantageously SMS (Short Message Service) or a corresponding data transmission system. When this inquiry is affirmatively answered in the second subject mobile station, the formation and transmission of position data through the mobile communications network to the first inquiring mobile station is initiated, and finally, the position of the second mobile station appears on the display of the first mobile station.

[0008] According to an advantageous embodiment of the invention, the mobile station comprises a mapping system, whereby, once the subject mobile station's position data has been received in the inquiring mobile station, the position data functions as the key information for displaying a map base on the display of the inquiring mobile station.

[0009] When the positioning service is implemented as a network service, the mapping system can be a PLMN element or a service provider system, which is in data transmission communication with a mobile phone center, whereupon the necessary map information can be added to the position data transmitted from the subject mobile station to the inquiring mobile station. Thus, one advantage is that less memory is necessary in the mobile station.

[0010] The invention will now be explained in more detail, by way of a certain advantageous embodiment, with reference to the accompanying drawing, in which

[0011] FIG. 1. diagrammatically illustrates a positioning system, according to the invention, which uses GPS,

[0012] FIG. 2 illustrates. with a flow chart, the process of a positioning method, which uses GPS, according to the invention, and

[0013] FIG. 3 illustrates, with another flow chart, a computer program, according to the invention, for controlling a positioning system which uses GPS and a mobile communications network PLMN.

[0014] As FIG. 1 illustrates, a system formed according to the invention comprises a mobile communications network PLMN (Public Land Mobile Network), the base stations (BS) which are in communication with mobile communications stations MS1 (Mobile Station 1) and MS2 (Mobile Station 2) via a wireless radio channel. The mobile communications network PLMN differs from fixed telecommunications networks, in that the mobile communications stations MS1 and MS2 can move within the entire network area, and they are involved in active communication with the mobile communications network PLMN. A fixed telecommunications network is a passive network, in which communication between the terminal and the network can only occur from the terminal.

[0015] The present invention utilizes the basic characteristics of a mobile communications network PLMN, which can be, for example,

[0016] GSM (Global System for Mobile Communications), 900, 1800/1900

[0017] PCS (Personal Communications Services)

[0018] D AMPS (Digital American Mobile Phone System),

[0019] PDC (Personal Digital Cellular)

[0020] UMTS (Universal Mobile Telecommunications System).

[0021] Mobile communications network PLMN terminals are not technically bound to a defined location, such as an electrical network or stationary communications tele-network connection, and an essentially broad, encompassing service area is characteristic to a mobile communications network. Additionally, in a system formed according to the invention, the mobile communications stations MS1 and MS2 comprise a combination of a mobile communications system intended for telecommunications, and a GPS receiver for navigation. Thus, a terminal formed according to the invention is able to determine its own position data using GPS (Global Positioning System) satellite 2, and to transmit its position data to the mobile communications network PLMN.

[0022] In the mobile communications network, regardless of the type of network, short message and/or data transmission has been pre-defined, and/or standardized, without exception, and therefore is already known to professionals in the field. Concerning these, reference here is only being made to network-related recommendations, stipulations and standards. For example, ETSI publications GSM 04-11, GSM 03-40 and GSM 07-05 relate to the transmission of short messages in GSM and/or UMTS mobile communications network.

[0023] In a recommended embodiment of the invention. in addition to a program memory, the GPS/GSM mobile station also comprises a mapping system or database 1, whereupon using the GPS satellite map coordinates and a map base, based on the map coordinates obtained from the mapping database, the position of a GPS/GSM mobile station, at any given time, can be made graphically visible on the map base. When an inquiry for position data is sent as a data transmission using a data transmission method which supports mobile communications networks, advantageously SMS or a corresponding method, from the first inquiring mobile station MS1 to the second mobile station MS2, and when this position data inquiry is affirmatively answered at the second mobile station MS2, an action is triggered, which joins the map coordinates and the map base, and encloses this body of data into the first mobile station as a reply message, using data transmission based on a data transmission method, which supports the mobile communications network, advantageously SMS, GSM-data, or corresponding method. The first mobile station MS1 automatically or manually decodes the received reply using the menu function, and shows the position of the second mobile communications station MS2 on a map base on its display.

[0024] In this context, it must be noted, that it is not necessary to include a map base indicating the position of the second mobile station MS2 in the reply message being formulated in the second mobile station for transmission to the inquiring mobile station MS1; rather, alternatively, only the map coordinates, which were obtained using GPS, are transmitted from the second mobile station MS2, and a map base is selected from the mapping system or database 1 in the first mobile station MS1, on the basis of these map coordinates of the second mobile station MS2, and the position data of the second mobile station appears on the display of the inquiring mobile station MS1 on a map base.

[0025] Further, it must be noted, that the mapping system or database 1, can also take the form of a mobile communications network PLMN element. Thus, it would not be necessary to equip any of the mobile stations MS with a mapping system or database. Instead, only coordinate data about the positioning of the second mobile station MS2 obtained using GPS is transmitted from the second station MS2 as a reply to the position data inquiry to the PLMN. The coordinate data forms the basis according to which the map base is added from the mapping system or database to the coordinate data, and this comprehensive body of data is then transmitted as a data transmission, using a transmission method supported by a mobile communications network, advantageously SMS or other such method, to the first mobile station MS1, which decodes the received data message, either automatically or manually, for example, using the menu function, and shows the positioning of the second mobile station MS2 on its display on a map base.

[0026] The mapping system or database 1 can also be implemented using a service provider system (not illustrated in FIG. 1) which is in communication with a mobile communications network PLMN. Thus, it would not be necessary to equip any of the mobile stations MS with a mapping system or database, whereupon the first connection to the service provider system is made as a data transmission connection from the first mobile station MS1, advantageously via SMS or other data transmission method supported by a mobile communications network; a data transmission connection to the second mobile station MS2 then being further formed from the service provider system, advantageously in the form of an SMS transmission or other data transmission method supported by a mobile communications network, in order to transmit the position data inquiry, while the positioning coordinates for the second mobile station MS2, which are obtained using GPS, are transmitted as a reply to the position data inquiry, advantageously by SMS or other data transmission method supported by a mobile communications network, from the second mobile station MS2 as a data transmission to the service provider system, which is connected to the PLMN. This coordinate data then forms the basis used by the mapping system or database of the service provider to integrate the map base with the coordinate data. This comprehensive body of data is then transmitted, advantageously using SMS or other data transmission method supported by a mobile communications network, to the first mobile station MS1, which decodes the received data message, either automatically or manually, for example, using the menu function, and shows the position of the second mobile communications station MS2 on a map base on its display.

[0027] According to the invention, the second mobile station MS2 can reply to the position data inquiry automatically, whereupon there is a register connected to the program memory which is in the second mobile station MS2, and which controls the positioning system. The register is a record of those inquiring for positioning data, advantageously the subscriber number and A-connections of the inquirers, thus the second mobile station MS2 can respond automatically to position data inquiries made by those inquirers, according to the program which controls the system. According to the invention, the reply to the position data inquiry made by the second mobile station MS2 can also be made manually, whereupon, according to the computer program which runs the system, a selection can be made at the second mobile station MS2, to either enable the reply, or to disable it; according to the invention, it is advantageous to base the selection on the menu function of the program which runs the system.

[0028] According to the invention, the decode and display position inquiry item on the computer program which controls the positioning system in the first mobile station MS1, decodes the received data message and shows the position of the second mobile station MS2 on a map base on the display at the first mobile station MS1, either manually, for example using the menu function included in the computer program, or automatically, immediately and directly controlled by the computer program.

[0029] FIG. 2 illustrates a computer-controlled GPS and a positioning system which uses a mobile communications network PLMN, according to the invention, for manually determining the position of the desired second independent mobile station MS2, from the inquiring, first independent mobile station MS1. This kind of computer-program-operated comprehensive system minimally comprises the phases:

[0030] Formation of the position inquiry in the first mobile station MS1,

[0031] Transmission of the position inquiry from the first mobile station MS1,

[0032] Reception of the position inquiry at the second mobile station MS2,

[0033] Determination of the positioning of the second mobile station MS2 in the second mobile station,

[0034] Transmission of the reply to the position inquiry from the second mobile station,

[0035] Reception of the position inquiry reply at the first mobile station MS1, and

[0036] Display of the second mobile station's MS2 positioning at the first mobile station MS1.

[0037] When the invention concerns the tracking of a second independent mobile station MS2, independent of the first independent mobile station MS1, the computer program which runs the system, according to an advantageous embodiment of the invention, comprises at least two parts, such that the items of the computer program, which control the following phasesformation of the position inquiry, transmission of the position inquiry, reception of the position inquiry reply, and display of the positioning of the second mobile station MS2are set up in the first mobile station MS1, and such that the computer program items which control the following phases-reception of the position inquiry, determination of the second mobile station's MS2 position, and transmission of the reply to the position inquiryare set up in the second mobile station MS2.

[0038] In order to enable the position of the second mobile station MS2 to appear on the display of the first mobile station MS1 on a map base, the computer program includes an additional phase, whereby the map information corresponding to the position of the second mobile station MS2 is incorporated into the position inquiry reply message from the second mobile station MS2. The computer program item which controls this phase is thus in the second mobile station MS2.

[0039] The position of the second mobile station MS2 can also appear on the first mobile station's MS1 display on a map base thus; the computer program includes an additional phase, in which the map information corresponding to the positioning of the second mobile station MS2, is integrated into the position inquiry reply after the position inquiry reply has been received at the first mobile station MS1. Thus, the computer program item which controls this phase is in the first mobile station.

[0040] If the mapping system or database in a system according to the invention is set up for a PLMN, or for a service provider system which is in communication with a PLMN, the item of the computer program which controls the integration of the map information with the position data of the second mobile station, which is included in the position data inquiry reply, is correspondingly adapted either to the PLMN element or to the service provider system, to which the mapping system or database is connected.

[0041] FIG. 3 illustrates, in the form of a flow chart, a computer program, according to the invention, for controlling a positioning system and method which uses GPS and a mobile communications network PLMN, with the objective of determining the position of the second independent mobile station MS2 from the first independent mobile station MS1.

[0042] When run by a computer program, the following phases occur consecutively after the positioning process has been activated or initiated:

[0043] formation of the position inquiry in the first mobile station MS1,

[0044] transmission of the position inquiry from the first mobile station MS1, whereupon the second independent mobile station MS2 is the destination address in the transmission,

[0045] reception of the position inquiry at the second mobile station MS2,

[0046] determination of the positioning of the second mobile station MS2 using GPS in the second mobile station,

[0047] transmission of the reply to the position inquiry from the second mobile station MS2, whereupon the first mobile station MS I is the destination address in the transmission,

[0048] reception of the position inquiry reply at the first mobile station MS1,

[0049] display of the second mobile station's MS2 positioning at the first mobile station MS1.

[0050] According to a specific embodiment of the invention, the position of the second mobile station MS2 is shown on the display of the first mobile station MS1 on a map base. In order for this to happen, there is a mapping system or database 1 in the first mobile station, from which, on the basis of the position of the second mobile station MS2, the correct map base information is obtained, so that it is incorporated into the position data inquiry reply transmitted to the first mobile station MS1. Alternatively, the position inquiry reply transmitted from the second mobile station MS2 may only include the position coordinates of the second mobile station MS2, and the first mobile station MS1 then has a mapping system or database 1, from which, on the basis of the position of the second mobile station MS2, the correct map base can be obtained after the position inquiry reply has been received, to be displayed integrated at the first mobile station MS1. It must still be stated, that the mapping system or database 1 can also be set up for a PLMN, or for a service provider system which is in communication with a PLMN, whereupon the map base is incorporated into the position inquiry reply transmitted in the PLMN, or service provider system which is in communication with a PLMN, from the second mobile station MS2, and the position of the second mobile station MS2 is shown on a map base on the display of the first mobile station MS1.

[0051] The invention has only been explained above by way of its alternative examples of application and by way of its certain advantageous embodiment. This is naturally not to be limited in any way, and, as is evident to the professionals of the field, many alternative applications and variations are possible within the scope of the frames of the new and inventive idea, defined in the accompanying claims.