Handover between mobile communication networks

Abstract

The invention provides a method of handover from an active network to a selected one of a plurality of potential other networks. In addition to the overall solution, the solution proposed has several individual aspects. All subsidiary aspects are related to the common problem mentioned above and sharing the underlying common solution concept of implementing a system in which selective handover is possible and in which a list of available other networks provided by an active network can be handled and selection made by a terminal, so that neighbor cell information can be transmitted based on expressed terminal preferences.

1 . A method of facilitating handover from an active network with which User Equipment is in communication to another network, the method comprising the steps of: 
 providing a list of available other networks to said User Equipment via the active network;    in the User Equipment, selecting among the available networks based on preference information and signalling to said active network at least one preferred other network; and    providing neighbor cell information for the at least one preferred other network to said User Equipment via the active network.    
     
     
         2 . A method of facilitating handover from an active network with which User Equipment is in communication to another network, the method comprising a step of providing to User Equipment communicating via the active network a list of available other networks.  
     
     
         3 . (canceled)  
     
     
         4 . A method of operating User Equipment capable of handover between an active network and another network comprising a step of storing in the User Equipment a list of available networks based on information supplied by the active network with which the User Equipment is in communication.  
     
     
         5 . (canceled)  
     
     
         6 . A method according to  claim 2  further comprising a step of sending a message to the User Equipment containing information for incrementally adding to or subtracting from the list of available networks.  
     
     
         7 . A method of operating an active network to facilitate handover to another network comprising a step of providing to User Equipment communicating via the active network a message containing information for incrementally adding to or subtracting from a stored list of available networks.  
     
     
         8 - 10 . (canceled)  
     
     
         11 . A method of operating an active network with which User Equipment is in communication comprising a step of sending neighbor cell information to User Equipment based on network preferences communicated by the User Equipment.  
     
     
         12 . A method according to  claim 11  comprising a step of sending mutually different neighbor cell information to mutually different User Equipments based on mutually different network preferences.  
     
     
         13 . A method according to  claim 1 , wherein the preferred other network is selected based on information stored in the User Equipment, preferably in a SIM card.  
     
     
         14 . A method according to  claim 1 , wherein the active network is a UMTS network and the other network is selected from available GSM networks.  
     
     
         15 . A method according to  claim 1 , wherein the active network is provided by an active network provider and the other network is selected from networks provided by other network providers.  
     
     
         16 - 18 . (canceled)  
     
     
         19 . User Equipment for a mobile communications system capable of handover from an active network with which User Equipment is in communication to another network comprising means for signalling a preferred other network to the active network during a call.  
     
     
         20 - 21 . (canceled)  
     
     
         22 . A mobile communications network or component thereof including means for communicating to User Equipment communicating with the network a list of available other networks.  
     
     
         23 . A mobile communications network or component thereof according to  claim 22  having means for sending a message to me User Equipment containing information for incrementally adding to or subtracting from the list of available networks.  
     
     
         24 . A mobile communications network or component thereof including means for sending a message to User Equipment containing information for incrementally adding to or subtracting from a list of available networks stored in the User Equipment.  
     
     
         25 . (canceled)  
     
     
         26 . A mobile communications network or component thereof including means for sending neighbor cell information to User Equipment based on network preferences communicated by the User Equipment.  
     
     
         27 . A mobile communications network or component thereof according to  claim 26  arranged to send mutually different neighbor cell information to mutually different User Equipments based on mutually different network preferences.  
     
     
         28 . A system for facilitating handover from an active network with which User Equipment is in communication to another network, the system comprising: 
 means for providing a first list including at least one unique network identifier to a user equipment via an active network; and    means for comparing the provided first list with a second list internally stored in the user equipment, the second list containing at least one unique network identifier, and the comparing means being provided in the user equipment.    
     
     
         29 . A method for facilitating handover from an active network with which User Equipment is in communication to another network, the method comprising: 
 providing a first list including at least one unique network identifier to a user equipment via an active network; and    comparing the provided first list with a second list internally stored in the user equipment, the second list containing at least one unique network identifier, and the comparing being performed in the user equipment.