Location management in a mobile telecommunication system

Abstract

The basic idea of the invention is to separate the location area used in the RAN and the reporting area used when reporting the location of the mobile to the core network. The size of the location area is selected preferably in the RAN based on the services used by the subscriber to optimize the use of radio resources. A reporting area comprises one or a plurality of location areas. The size of a reporting area is selected based on the accuracy of location information needed in the core network. The RAN informs the core network when a subscriber moves out of his current location area. The core network and the radio access network negotiate the size of the reporting area prior to the activation of the service. Additionally, the reporting areas can be renegotiated when the service is in the active state.

What is claimed is: 
     
       1. A method of location management in a mobile telecommunication system comprising mobile stations, at least one core network providing telecommunication services, and a radio access network providing connections between the mobile stations and the core network, and in which system information concerning the location of the mobile station is stored in the radio access network, comprising
 tracking in the radio access network of the location of the mobile station to the accuracy of a location area,   determining in the core network a reporting area comprising at least one location area,   informing the radio access network by the core network of the reporting area determined,   receiving at the radio access network a location update from the mobile station,   determining by the radio access network based on the location update whether or not the mobile station has moved out of the reporting area, and   sending by the radio access network to the core network a report if the mobile station has moved out of the reporting area.   
     
     
       2. The method according to  claim 1 , A method of location management in a mobile telecommunication system comprising mobile stations, at least one core network providing telecommunication services, and a radio access network providing connections between the mobile stations and the core network, and in which system information concerning the location of the mobile station is stored in the radio access network, comprising
 tracking in the radio access network of the location of the mobile station to an accuracy of a location area, 
 determining in the core network a reporting area comprising at least one location area, 
 informing the radio access network by the core network of the reporting area determined, 
 receiving at the radio access network a location update from the mobile station, 
 determining by the radio access network based on the location update whether or not the mobile station has moved out of the reporting area, 
 sending by the radio access network to the core network a report if the mobile station has moved out of the reporting area; and 
 not sending the core network said report if the mobile station has not moved out of the reporting area, 
 wherein a plurality of location accuracy levels is defined, each location accuracy level having location areas of different sizes, and the radio access network selects one of these accuracy levels to be used for tracking the mobile station. 
 
     
     
       3. The method according to  claim 2 , wherein the reporting area is a location area of one location accuracy level. 
     
     
       4. The method according to  claim 2 , wherein the radio access network selects the location accuracy level based on the services currently used by a subscriber using the mobile station. 
     
     
       5. The method according to  claim 2 , wherein the radio access network selects the location accuracy level based on service parameters given by the core network. 
     
     
       6. The method according to  claim 2 , wherein the radio access network selects the location accuracy level based on the past behavior of a subscriber using the mobile station. 
     
     
       7. The method according to  claim 6 , wherein the behavior of the subscriber is determined based on the number of pages that the radio access network has performed to locate the mobile station and the number of location updates that the mobile station has performed. 
     
     
       8. The method according to  claim 2 , wherein the radio access network informs the mobile station of the location accuracy level to be used when tracking the mobile station. 
     
     
       9. The method according to claim  1  2, wherein the core network requests that a mobile station reauthenticates itself when the mobile station moves to a new reporting area. 
     
     
       10. The method according to  claim 1 , wherein the mobile station is entitled to different services in different reporting areas. 
     
     
       11. The method according to claim  1  2, wherein the mobile station is entitled to different qualities of service in different reporting areas. 
     
     
       12. The method according to claim  1  2, wherein the core network and the radio access network negotiate the size of the reporting area to be used. 
     
     
       13. The method according to  claim 12 , wherein the negotiation takes place when the service is activated. 
     
     
       14. The method according to  claim 12 , wherein the negotiation takes place when the service is in an activated state. 
     
     
       15. The method according to claim  1  2, wherein the service parameters for different service areas for the services a subscriber using the mobile station has subscribed to are specified and stored in the core network,
 the mobile station initiates a location update process when entering into a new reporting area, 
 in response to having received the location update, the radio access network forwards the new location information of the mobile station to the core network, 
 the core network receives the new location information and defines a new service area for the subscriber, checks the service parameters of services the subscriber is entitled to in the new service area, and sends the radio access network information about the new service parameters, 
 the radio access network receives the information about the new service parameters and completes the location update process by sending the mobile station a response. 
 
     
     
       16. The method according to  claim 1 , wherein information about reporting area configuration is stored in the mobile station, and when entering a new service area, the mobile station initiates a location update process, instructing the radio access network to forward the new location information to the core network, and
 the radio access network forwards the location information to the core network.   
     
     
       17. The method according to  claim 16 , wherein the information about the service area configuration is given as a list of cells. 
     
     
       18. The method according to  claim 16 , wherein the information about the reporting area configuration is given as coordinates of the reporting area and the mobile station observes its coordinates and initiates a location update when entering into a new reporting area. 
     
     
       19. The radio access network for a mobile telecommunication system comprising mobile stations, at least one core network providing telecommunication services, and a radio access network, providing connections between the mobile stations and the core network, and in which system information concerning the location of the mobile station is stored in the radio access network, the radio access network adapted to
 use a location area configuration to track the location of the mobile station on the accuracy of one location area,   receive information on a reporting area determined by the core network,   receive a location update from the mobile station,   determine, based on the location update, whether or not the mobile station has moved out of the reporting area, and   send the core network a report if the mobile station has moved out of the reporting area.   
     
     
       20. The network element for a radio access network of a mobile telecommunication system comprising mobile stations, at least one core network providing telecommunication services, and a radio access network providing connections between the mobile stations and the core network, and in which system information concerning the location of the mobile station is stored in the radio access network, the network element adapted to
 use a location area configuration to track the location of the mobile station on the accuracy of one location area,   receive information on a reporting area determined by the core network,   receive a location update from the mobile station,   determine, based on the location update, whether or not the mobile station has moved out of the reporting area, and   send the core network a report if the mobile station has moved out of the reporting area.   
     
     
       21. The core network for a mobile telecommunication system comprising mobile stations, at least one core network providing connections between the mobile stations and the core network, and in which system information concerning the location of the mobile station is stored in a radio access network, and the radio access network uses a location area configuration to track the location of the mobile station on the accuracy of one location area, the core network adapted to
 determine a service area comprising at least one location area,   inform the radio access network of the reporting area determined, and to   receive a report from the radio access network when the mobile station has moved out of the reporting area.   
     
     
       22. A method, comprising: tracking a location of a mobile station in a radio access network with an accuracy of a location area, the radio access network providing connections between mobile stations and a core network providing services to the mobile stations;
 determining a reporting area comprising at least one location area;   determining a change in the location of the mobile station when the mobile station moves from a first location area to a second location area;   reporting to the core network the change in the location of the mobile station only when the mobile station also moves from a first reporting area to a second reporting area; and   not reporting to the core network the change in the location of the mobile station when the mobile station has not moved from the first reporting area to the second reporting area,   wherein the core network requests that a mobile station authenticates itself when the mobile station moves to a new reporting area.   
     
     
       23. The method according to claim 22, wherein the mobile station is entitled to different qualities of service in different reporting areas. 
     
     
       24. The method according to claim 22, wherein the core network and the radio access network negotiate the size of the reporting area to be used.