Unlicensed-radio access networks in a mobile communications system

• US 8,014,776 B2
• Filed: 02/18/2004
• Issued: 09/06/2011
• Est. Priority Date: 02/18/2004
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Vikberg, Jari Tapio, Nylander, Tomas
• Primary Examiner(s): DOAN, PHUOC HUU
• Application Number:
  US10/589,873
• Publication Number:
  US 20080242298A1
• Time in Patent Office: 2,757 Days
• Field of Search: None
• US Class Current: 455/435.2
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

Cellular mobile networks can include unlicensed-radio access networks, which comprise access point controllers connected via a fixed broadband network to access points that communicate with mobile stations via unlicensed radio. The access points are connected to the broadband network from any location by the subscriber. In order to alleviate the configuration required to enable handover each access point controller is assigned to a location area defined in the conventional cellular network. A mobile station entering the mini-cell of an access point sends the access point information concerning the location area for the last cell of conventional network it communicated with. With this information, the access point obtains from a memory the fixed broadband address of the access point controller assigned to this location area. The access point uses this address to establish a connection with the access point controller assigned to handle its current location.

Claims

1. A mobile telecommunications network including:

a plurality of base station systems arranged to communicate with a mobile terminal over a predetermined licensed radio interface and switching centers connected to a plurality of said base station systems wherein each switching center and the base station systems connected thereto share a location area identity, said base station systems being adapted to communicate information indicative of said location area identity to a mobile terminal,

wherein said network further includes at least two unlicensed-radio access networks, each comprising an access network controller connected to one of said switching centers, multiple access points adapted to communicate with said mobile terminal via an unlicensed-radio interface and a broadband network connecting said plurality of access points with said access network controllers and a lookup table mapping a location area identity with address information for an access network controller on said broadband network, and

wherein each said access point is arranged to connect a mobile terminal with a default access network controller, said default access network controller being adapted to receive a request from said mobile terminal containing information indicative of a last location area received by said mobile terminal, to submit a request to said lookup table containing said location area information, to receive address information from said lookup table for an access network controller mapped to said location area in response to said request, and to transmit said address information to said mobile terminal via said access point, said address information enabling said mobile terminal to establish a connection with said addressed access network controller via said access point and said broadband network.

2. A network as claimed in claim 1, wherein said mobile terminal is adapted to store at least part of said lookup table.

3. A network as claimed in claim 1, wherein said default access network controller is adapted to store at least part of said lookup table.

4. A network as claimed in claim 1, wherein said broadband network is an internet protocol based network and said address is an internet protocol address.

5. An unlicensed-radio access system connected to a core network portion of a licensed mobile network, said unlicensed-radio access system including:

a plurality of access points adapted to communicate with mobile stations over an unlicensed-radio interface, a plurality of access network controllers connected to said core network portion and a broadband network connected to both said access points and said access network controllers,

wherein each said access network controller is associated with a location area in said licensed radio mobile network,

said system furthermore being provided with at least one lookup table containing information mapping location areas to address information of access network controllers on said broadband network,

wherein each access point is arranged to receive from a mobile station information indicative of a location area corresponding to a portion of said licensed mobile network, to obtain from said lookup table address information of an access network controller on said broadband network associated with said location area information, and to establish a connection with said addressed access network controller via said broadband network.

6. A system as claimed in claim 5, wherein said lookup table is comprised in a database server located on said broadband network.

7. A system as claimed in claim 5, wherein said access points are arranged to store at least part of the data in said lookup table.

8. A system as claimed in claim 5 or 6, wherein said fixed broadband network is an internet protocol based network and said address is an internet protocol address.

9. A system as claimed in claim 5, wherein each access point is connected for communication with a default access network controller, wherein the access points are arranged to connect to a different access network controller if the information indicative of a location area does not correspond to the broadband network address of said default access network controller.

10. A method for establishing a connection between a mobile terminal and a core network portion of a mobile communications network via an unlicensed-radio access network, said mobile communications network comprising:

access portions including base stations and switching control parts connected to said base stations, each switching control part sharing a common location area identity with a plurality of said base stations and said base stations being arranged to communicate said location area identity to a mobile terminal, said unlicensed-radio access network comprising at least one access point arranged to communicate with a mobile station via an unlicensed-radio interface, at least one access network controller each connected to a switching control part, a broadband network connected to said at least one access network controller and access point and a lookup table containing data mapping a location area identity with an address of one of said access network controllers on said broadband network, said method including the steps of;

a default access network controller receiving information indicative of a location area identity from a mobile terminal via an access point;

said default access network controller submitting a request to said lookup table using said location area identity information;

receiving from said lookup table an address on said broadband access network of an access network controller associated with said location area identity; and

relaying said address to said mobile terminal via said access point to enable said mobile terminal to establish a connection with said addressed access network controller via said access point and broadband network.

11. A method in an unlicensed radio access network for assigning and connecting access points to an access network controller, said unlicensed radio access network including a plurality of access points a plurality of access controllers connected to a licensed mobile core network and a broadband network connected to said access controllers and for connecting to said access points, and wherein each access network controller is associated with a location area of said licensed mobile network, said method including the steps of:

receiving from said mobile station a location area indicator indicative of a location area of said licensed mobile network with which said mobile station was last in communication,

retrieving broadband network address information for an access point switching controller associated with said location area indicator, and

connecting said access point to said retrieved broadband network address of said an access point switching controller to establish a connection.

12. An unlicensed-radio access network controller connected to a core network portion of a licensed mobile network and to a plurality of access points via broadband network, wherein said access network controller is arranged to communicate with a lookup table containing information mapping location areas to address information for addressing access network controllers on said broadband network,

said access network controller being further arranged:

to serve a mobile terminal as a default access network controller, and

to receive from said mobile terminal information indicative of a location area corresponding to a portion of said licensed mobile network,

to obtain from said lookup table address information of an access network controller on said broadband network associated with said location area information, and

to transmit said address information to said mobile station.