PROVIDING LOCATION-DEPENDENT SERVICES

Abstract: A method of providing a location-dependent service to a mobile station (MS) in a telecommunication network, to which the mobile station (MS) and a service provider are connected, in which method discrete messages are transferred between the mobile station (MS) and the service provider via the telecommunication network. A radio link between the mobile station (MS) and the telecommunication network is kept active longer than is necessary to transfer one discrete message, the location information on the mobile station (MS) is retrieved (2-7 to 2-12) from the telecommunication network during said radio link, the location-dependent service is generated (2-13) based on said location information, and a service message including the location-dependent service is sent (2-14) to the mobile station (MS).

Description: PROVIDING LOCATION-DEPENDENT SERVICES BACKGROUND OF THE INVENTION [0001] The invention relates to a method and a system for providing location-dependent services in a telecommunication network by means of dis- crete messages and particularly by means of short messages, i.e. SMS (Short Message Service) messages. [0002] In this context, a telecommunication network refers to any telecommunication system using wireless communication when users move within the service area of the system, such as the GSM system (Global System for Mobile Communications) or the UMTS system (Universal Mobile Telecommunications System) or any similar system. [0003] The number of services provided in a wireless telecommunication network can be increased by providing location-dependent value added services, i.e. value added services tailored based on the location of a user. Such value added services include local weather forecasts, information on local entertainment services, timetables, traffic, and positioning the nearest service points, such as a pharmacy or the police, and the user of a moving terminal in an emergency. [0004] There are several methods of locating a mobile station within the area of a telecommunication network. Typically, measurement data provided by an active mobile station in the telecommunication network are used for determining the location, for example to implement handover and to control the quality of a call. Such measurement data include cell identity (CID), location area (LAC), the radio channel used and its strength, timing advance and the channels of surrounding radio cells and their strengths. For example, the MAPv3 (Mobile Application Part) Any Time Interrogation (ATI) function can be used in the GSM system to inquire the location information on a mobile station of a mobile switching centre (MSC) when a radio link exists between the mobile station and the telecommunication network. The ATI function provides the location of a mobile station at the accuracy of a cell, which is a sufficient accuracy for providing most location-dependent value added services. However, the invention does not directly relate to location determination per se, and thus, the details of location determination are not relevant to the present invention. Location determination is described in the 3GPP specification: 3G TS 22.071 v3.2.0, Location Services (LCS), Service Description, stage 1 , which is incor- porated herein by reference. [0005] However, the location information obtained by for instance the ATI function is accurate (at the accuracy of a cell) only if the GSM network has a radio link to the mobile station (the mobile station is active) when the location information is inquired. When short messages are sent from or received at the mobile station, the radio link is only active a short time and receiving accurate location information is therefore uncertain. Present arrangements cannot therefore provide location-dependent services reliably via short messages by automatically determining the location of the mobile station. [0006] In known solutions, location-dependent services can be used by determining the location area in the service request. The user of the service has to determine e.g. the neighbourhood, based on which the location- dependent service is generated. [0007] Figure 1 shows an example of a prior art signalling diagram. In step 1-1 , a service request message identifying the service requested and the location is sent from a mobile station via a short message service centre (SMSC) to a service provider. In step 1-3, the service is generated based on the location indicated and in step 1-6, a service message including the service requested is returned to the mobile station via the SMSC. Said service request message may be e.g. 'WEATHER TAMPERE', the answer being the weather forecast for the Tampere neighbourhood. [0008] When the above-described method is used to provide services based on more accurate than neighbourhood-specific location information, such as services indicating the location and opening hours of the nearest hotel or restaurant, the number of areas would, however, increase so high as to complicate the use of the services. In view of the flexibility and user-friendliness of location-dependent services, it would be appropriate to provide, via short messages, services for which the location of the mobile station is determined automatically. DESCRIPTION OF THE INVENTION [0009] The object of the invention is thus to provide a method and equipment implementing the method so as to solve the above problems. The objects of the invention are achieved with a method and a system, which are characterized in what is stated in the independent claims. The preferred em- bodiments of the invention are disclosed in the dependent claims. [0010] The invention is based on prolonging a radio link between a mobile station and a telecommunication network to obtain the location information on the mobile station when the mobile station and the telecommunication network communicate by means of discrete messages, preferably SMS mes- sages, in which case the radio link between the mobile station and the telecommunication network is active only a short time. In other words, the radio link between the mobile station and the telecommunication network is kept active longer than is necessary to transfer one discrete message. [0011] In the method of the invention, discrete messages are trans- ferred between a mobile station and a service provider via a telecommunication network. The radio link between the mobile station and the telecommunication network is kept active longer than is necessary to transfer one discrete message, and the location information on the mobile station is retrieved from the telecommunication network during said radio link. The location-dependent service is then generated based on said location information, and a service message including the location-dependent service is sent to the mobile station. [0012] In accordance with an embodiment of the invention, a service request message requesting a location-dependent service is sent from a mobile station, and in response to the service request message an acknowl- edgement message is sent, which is delayed to prolong the radio link. [0013] In accordance with another embodiment of the invention, the radio link is prolonged by sending, to the mobile station, a wait message requesting the mobile station to wait for the next message. The wait message can be sent in response to a service request message or it may be sent on the service provider's initiative without a service request message being sent from the mobile station. [0014] The method and the system of the invention provide the advantage that the location information on a mobile station is obtained for the use of a service provider when the mobile station and the telecommunication net- work communicate by means of discrete messages. This allows location- dependent services, wherein the location of the mobile station is determined automatically, to be provided via short messages. The invention is simple to implement for example in the GSM system and it does not require major changes since the standardized properties of the GSM can be used in the in- vention. LIST OF THE FIGURES [0015] The invention will be described in detail in association with preferred embodiments with reference to the attached drawings, wherein Figure 1 shows an example of a prior art signalling diagram; Figure 2A is a block diagram of a system of the invention; Figure 2B is a signalling diagram of a method of an embodiment of the invention; Figure 3 is a signalling diagram of a method of another embodiment of the invention; Figure 4 is a signalling diagram of a method of still another embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION [0016] In the following, the invention is described in association with the GSM system and short messages to better describe the features of the invention. However, the invention is applicable to any corresponding system. [0017] Figure 2A is a block diagram of a system of the invention, the system comprising a telecommunication network 20 comprising a mobile services switching centre MSC/VLR with an associated visitor location register, a home location register (HLR) communicating with the mobile switching centre, a base station subsystem (BSS) that comprises one or more base stations (BS) and a base station controller (BSC), and via which the MS is connected to the telecommunication network 20. The system also comprises a service control point (SCP), via which a service provider 21 is connected to the telecommunication network, and a short message service centre (SMSC) that transfers short messages between the mobile station and the ' service provider. In accordance with the invention, the SMSC is arranged to determine or receive information about the need for location information on an MS, and, based on this information, to keep the radio link between the MS and the telecommunication network active longer than is necessary to transfer one short message. All sys- tern components are known from the GSM system, and are therefore not explained in more detail herein. [0018] Figures 2B, 3 and 4 show signalling diagrams according to some embodiments of the invention. In these signalling diagrams, like references are employed to designate like steps. The hatched bars on the left side of the signalling diagrams denote the duration of a radio link between a mobile station and a telecommunication network. [0019] Figure 2B is a signalling diagram of a system of an embodiment of the invention, wherein a radio link between a mobile station and a service provider is prolonged by sending, to the mobile station, a wait message requesting the mobile station to wait for the next message. The wait message is sent in response to a service request message. [0020] In step 2-1 , a service request message requesting a location- dependent service is sent from the mobile station MS to a short message centre SMSC. The SMSC transfers the service request message further to the service provider and acknowledges the service request message as received to the MS in step 2-3. In response to the service request message, in step 2-4, the service provider sends a wait request requesting the location information on the MS to the SMSC, in response to which request, in step 2-5, the SMSC sends, to the MS, a wait message requesting the MS to wait for the next mes- sage. In the exemplary GSM system, this is implemented by setting a GSM More Messages to Send parameter on in the wait message, whereby the radio link between the MS and the telecommunication network is not disconnected once the wait message arrives, but the radio link is kept active, and the MS waits for the next short message. If need be, several wait messages may be sent to keep the link active even longer. If several wait messages are sent, they are preferably always written on the previous wait message in the MS. In the GSM system, this is implemented by the setting TP-Protocol Identifier = Replace Short Message Type x in the wait message. In step 2-6, the MS acknowledges the wait message as received. [0021] In steps 2-7 to 2-12, during said radio link, the service provider requests the location information on the MS of the SCP, which inquires it by means of an ATI function of the HLR, and then the HLR in a PSI message (Provide Subscriber Info) of the MSC/VLR, and the location information is returned to the service provider along the same path. However, returning the location information does not necessarily require the inquiry for the subscriber info, but the SCP may alternatively inquire the subscriber info of the MSC/VLR by means of the PSI message only after the location info is returned (step 2- 12). Next, in step 2-13, the service provider provides the requested location- dependent service on the basis of the location information received. In step 2- 14, the MS is sent a service message including the location-dependent service and in step 2-16, the MS acknowledges the service message as received to the SMSC. The service message is preferably written on the wait message in the MS to avoid unnecessary filling of the memory of the MS. [0022] Figure 3 is a signalling diagram of a method of another embodiment of the invention, wherein the radio link between a mobile station and a service provider is prolonged by delaying an acknowledgement message to be sent to the mobile station in response to a wait message. [0023] As in Figure 2B, in step 2-1 , a service request message requesting for a location-dependent service is sent from the MS to the SMSC. The SMSC forwards the service request message to a service provider, but detects in step 2-2 from the service request message that location information is required. Since location information is required, the SMSC does not yet acknowledge the service request message as received to the MS. Hence, the MS waits for an acknowledgement and, consequently, the radio link between the MS and the telecommunication network is not disconnected. For example in the GSM system, this allows a radio link to be kept active for about 10 seconds, which in most cases is sufficient for inquiring location information. [0024] In steps 2-7 to 2-12, during the radio link, the service provider requests location information on the MS of the SCP as was explained in association with Figure 2B. In step 3-3, the SMSC sends a delayed acknowl- edgement to the MS to the service request message sent in step 2-1 , as a result of which the radio link between the MS and the telecommunication network is disconnected. In step 2-13, the service provider generates the location- dependent service requested, based on the location information received, and in step 2-14 a service message including the location-dependent service is sent to the MS and the MS acknowledges it as received in step 2-16. [0025] Figure 4 is a signalling diagram of a method of still another embodiment of the invention, wherein the radio link between a mobile station and a service provider is prolonged by sending a wait message to the mobile station, requesting the mobile station to wait for ' the next message. This method is otherwise similar to the one shown in Figure 2B, but the service is now sent on the service provider's initiative without a service request message being sent from the mobile station. For example, the user may request a given location-dependent service regularly to his mobile station, such as a local weather or traffic report each morning. Such a service always relates to the area where the mobile station is located at any given time, even if the location of the mobile station changes day by day. [0026] In step 4-4, the service provider sends to the SMSC an initiate request indicating that the location information on the MS is required, and in response to which the SMSC sends a wait message to the MS in step 2-5, in which wait message the MS is told to wait for the next message, i.e. the radio link between the MS and the telecommunication network is kept active and the MS waits for the next short message. [0027] In steps 2-7 to 2-12, during said radio link, the service provider requests the location information on the MS, as was explained in association with Figure 2B, and in step 2-13, the service provider generates the requested location-dependent service on the basis of the location information received. Further, in step 2-14, the MS is sent a service message including the location-dependent service, and in step 2-16, the MS acknowledges the service message as received to the SMSC. The service message is preferably written on the wait message in the MS to avoid unnecessary filling of the memory of the MS. [0028] It is obvious to a person skilled in the art that as technology advances, the basic idea of the invention can be implemented in a variety of ways. The invention and its embodiments are thus not limited to the above examples, but may vary within the claims.

Claims: CLAIMS 1. A method of providing a location-dependent service to a mobile station (MS) in a telecommunication network (20), to which the mobile station (MS) and a service provider (21) are connected, in which method discrete messages are transferred between the mobile station (MS) and the service provider (21) via the telecommunication network (20), c h a r a c t e r i z e d by keeping a radio link between the mobile station (MS) and the telecommunication network (20) active longer than is necessary to transfer one discrete message, retrieving (2-7 to 2-12) the location information on the mobile station (MS) from the telecommunication network (20) during said radio link, generating (2-13) the location-dependent service based on said location information, and sending (2-14) a service message including the location-dependent service to the mobile station (MS). 2. A method as claimed in claim ^ c h a r a c t e r i z e d by sending (2-1) from the mobile station (MS) a service request message requesting a location-dependent service, detecting (2-2) from the service request message that the location information on the mobile station (MS) is required, sending (2-3) to the mobile station (MS) an acknowledgement message in response to the service request message, and in response to the location information being required, keeping the radio link between the mobile station (MS) and the telecommunication network (20) active longer than is necessary to transfer one discrete message by delaying the acknowledgement message. 3. A method as claimed in claim 1 , c h a r a c t e r i z e d by sending (2-1) from the mobile station (MS) to the service provider (21) a service request message requesting a location-dependent service, ' sending (2-4) from the service provider (21) to the telecommunication network (20) a wait request indicating that the location information on the mobile station (MS) is required, and keeping the radio link active between the mobile station (MS) and the telecommunication network (20) longer than is necessary to transfer one discrete message by sending (2-5) to the mobile station (MS) a wait message in response to the wait request, in which wait message the mobile station (MS) is requested to wait for the next message. 4. A method as claimed in claim 1, characterized by sending (4-4) from the service provider (21) to the telecommunication network (20) an initiate request indicating that the location information on the mobile station (MS) is required, and keeping the radio link active between the mobile station (MS) and the telecommunication network (20) longer than is necessary to transfer one discrete message by sending (2-5) to the mobile station (MS) a wait message in response to the initiate request, in which wait message the mobile station (MS) is requested to wait for the next message. 5. A method as claimed in claim 3 or 4, characterized by sending several wait messages to the mobile station (MS), and always writing the new wait message on the previous wait message in the mobile station (MS). 6. A method as claimed in claim 3, 4 or 5, characterized by writing the service message on the wait message in the mobile station (MS). 7. A method as claimed in any one of claims 1 to 6, character- i z e d by the discrete messages being short messages. 8. A system for providing a location-dependent service to a mobile station (MS), the system comprising a telecommunication network (20), to which the mobile station (MS) and a service provider (21) are connected, and a network element arranged to transfer discrete messages between the service provider (21) and the mobile station (MS), characterized in that the network element is arranged to: determine or receive information indicating that the location information on the mobile station (MS) is required, and, based on this information, keep a radio link between the mobile station (MS) and the telecom- munication network (20) active longer than is necessary to transfer one discrete message. 9. A system as claimed in claim 8, characterized in that said network element is a short message service centre (SMSC).

Inventors: BLOMBERG OLAVI, BLOMBERG, OLAVI
Applicants: BLOMBERG OLAVI, SONERA OYJ, BLOMBERG, OLAVI
Application year: 2001
Main classification: H04Q7
IPC codes: H04W4, H04W76