MXPA06008275A - Unlicensed-radio access networks in a mobile communications system - Google Patents

Abstract

Cellular mobile networks can include unlicensed-radio access networks, which comprise access point controllers (303) connected via a fixed broadband network (302) to access points (301) that communicate with mobile stations (1) 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 (40) 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.

Description

RADIO ACCESS NETWORKS WITHOUT A LICENSE IN A MOBILE COMMUNICATION SYSTEM FIELD OF THE INVENTION The invention relates to a mobile communication that combines both public mobile access networks and unlicensed access networks. The invention has specific relevance for the transfer of connections between public mobile networks and radio access networks without a license. BACKGROUND OF THE ART In any mobile communication system, such as a GSM network, active calls made between a mobile station and a base station must be handled through a different base station as the mobile station moves between different coverage areas. or cells. Depending on the way each of the cells is defined, the transfer may require the simple routing of an active call through a different BTS base station transceiver, through a different base station controller BSC or through a hub. MSC mobile services switching different. The transfer may also be necessary when capacity problems arise in a cell. The transfer requires a certain amount of operation and maintenance activities in the installation of a system, such as the definition of neighboring cells, as well as the base station controller BSC and the mobile services switching center MSC that controls the cell, defining which cell frequencies should be measured and what threshold value should be used to initiate the transfer. In a conventional GSM network, the base station controller BSC sends a list of predetermined frequencies to be measured to a mobile station MS. Two lists can be sent, a first list used for an inactive mode, such as when the mobile station MS is traveling, and a second list used for the active mode when a call is being made. This second list defines what frequencies the mobile station MS should measure and report. These lists contain a group of values that refer to absolute numbers of ARFCN radio frequency channels of neighboring cells. In addition to these frequency channel numbers, the base station controller BSC also knows the base station identity codes BSIC of all neighboring cells. The mobile station MS measures the frequency defined by these channel numbers and reports these measurements to the base station controller. In practice, the mobile station MS will report only the six best measurement values and only for the cell frequencies with which the mobile station can be synchronized and consequently receive an identity code that refers to the base station (BSIC). The measurement report returned to the base station controller BSC by the mobile station MS includes a reference to the absolute numbers of the ARFCN radio frequency channel, the base station identity codes (BSIC) and an indication of the strength of the signal downlink received. In fact, the report does not specify the exact absolute numbers of the ARFCN radio frequency channel but it refers to the position that this number occupies in the measurement list. Based on this report, the base signal controller BSC decides if a transfer is required and to which cell. The start of a transfer is made in accordance with the standard GSM mechanism for each vendor. Specifically, the base station controller sends a message to the mobile services switching center MSC connected to the base station controller BSC indicating that transfer is required. This message contains a cell identifier, encompassed in a CGI cell global identity, which defines the mobile country code, mobile network code, location area code and cell identifier for the cell to which the transfer is requested. The global cell identity CGI is found by the base station controller from a list using the base station identification code BSIC and the absolute number of radio frequency channel ARFCN obtained for the cell. With this global CGI cell identity, the mobile services switching center MSC can determine that another MSC handles the cell defined by the CGI value. Recent proposals have been made to expand conventional cellular networks by including access networks that use a low power radio license-free interface to communicate with mobile stations. Access networks are designed to be used together with the core elements of a standard public mobile network and consist essentially of unlicensed low power radio transceivers, plug-ins, or access points, each designated to establish a radio link without a license with a mobile MS session and a controller node or interface that connects the unlicensed radio transceivers with the mobile central network. Suitable unlicensed radio formats include digital enhanced wireless telecommunications (DECT), wireless LAN and Bluetooth. A mobile device capable of operating both in the standard air interface (for example, the Um interface) as the unlicensed radio interface means that the subscriber requires only one telephone for all environments. The access network is constructed in such a way that the central elements, such as the mobile switching centers MSC, of the public mobile network consider the interface mode as a conventional base station controller BSC. Said access network and said mobile station for use with the access network are described in European Patent Application Number EP-A-1 207 708. The content of this application is incorporated herein by reference. The low power and low range resulting from the unlicensed radio interface means that several access networks of this type can be provided in relatively close proximity, for example an access network per floor of an office building or in a private house. The connection between the unlicensed radio transceivers and the associated controller is provided through a fixed broadband network. Preferably, communication through this network uses the Internet Protocol IP which greatly facilitates the installation of the access network, allowing a subscriber to plug an unlicensed radio transceiver into his own home and therefore install a point radio access without license the same. However, the flexibility of such unlicensed radio access networks also presents difficulties. Since an access point can be freely installed and can be moved by a subscriber to a city, state or even a different country, but maintaining the connection with its original access network controller, the exact location of the access point can not be traced through the central network. This involves significant demands on the operation and maintenance activities that are required for the transfer to and from the radio access network without license, since the neighboring cells can change frequently. Likewise, restrictions on billing in certain areas may require the reassignment of a relocated access point to a more appropriate access controller, especially if the revenue from calls that originate from a specific access point must be accounted for in a specific region of a country. Taking into account the small size of access points to an unlicensed radio access network, it would be more economical for operators to configure each access point separately. However, it is also undesirable to leave the configuration task to the subscriber since said solution would present a tendency to error and therefore would not be reliable. In addition, providers would not want to configure access points differently depending on where they are installed. SUMMARY OF THE INVENTION It is therefore an object of the present invention to propose a system for managing the distribution of access points of an unlicensed radio access network that greatly simplifies the transfer to a mobile network with a conventional public license or from of a network of this type, such as GMS, UTMS or CDMA2000 to an unlicensed radio access network connected to the conventional network.

It is a further object of the present invention to propose a system for managing the distribution of access points of an unlicensed radio access network that overcomes the configuration problems in the installation of an access point. It is a further object of the present invention to propose a system for managing the distribution of access points of an unlicensed radio access network that simplifies billing procedures. These and other objects are achieved in a mobile telecommunication network, an unlicensed radio access system, to establish a connection between a mobile station and a central network portion of a mobile communication network through an access network of radio without a license and a method for assigning and connecting access points to an access point controller in an unlicensed radio access network in accordance with the present invention and defined in the claims. In essence, the configuration demands required to allow the transfer between a cell of a conventionally licensed radio cellular network and a minicell of an unlicensed radio access network even when the access points are continuously relocated are alleviated in accordance with this invention by assigning the interface nodes or access point controllers to the location area defined in the conventional cellular network. Location areas are conventionally defined by a mobile services switching center MSC and the base station controllers BSC and BTS base station transceivers connected there. A recently relocated or rebooted access point communicates with a mobile station that moves in its mini cell and receives from this mobile station information about the location area for the last conventional network cell with which the mobile station was in communication. With this information, the access point obtains from a memory, preferably organized as a 'look-up table,' the fixed broadband network address of the access point controller assigned to this location area. The access point then uses this address to establish a connection to the assigned access point controller to handle its current location. The fixed broadband access network is preferably an IP network, the address is therefore the IP address of the access point controller. The memory or search table can be located in the fixed broadband access network, for example, in a database server. It communicates with this database server preferably using at least a part of the location area information.

The search table can be accessed alternatively at the point of connection of the access point to the broadband access network. In a useful embodiment of the present invention, the access point can store at least a part of the information in the search table. For example, the access point could store the location area information and the address in relation to an access point controller to which the access point was previously connected. In this way, unnecessary requests to the search table can be avoided when the access point must be reinitialized, after a power outage, or when an access point is reinstalled in a preferred location after a trip out. In another advantageous embodiment of the invention, all access points can be connected to a default access point controller. When an access point receives a location area information, it is then transmitted to the default controller who can access the lookup table and return the required address. BRIEF DESCRIPTION OF THE DRAWINGS Further objects and advantages of the present invention will be apparent from the following description of the preferred embodiments which are provided by way of example with reference to the accompanying drawings. In the figures: Figure 1 shows schematically a part of a GSM network with an unlicensed radio access network, Figure 2 shows schematically the location area system in a conventional GSM network, Figure 3 schematically shows the system of location areas in a conventional GSM network extended by unlicensed radio access networks, Figure 4 schematically shows the elements required to distribute access points to a correct controller in an unlicensed radio access network, Figure 5 is a example of the signaling sequence between the elements illustrated in Figure 4, and Figure 6 illustrates schematically the principles of identification of minicells in an unlicensed radio access network of Figure 1. DETAILED DESCRIPTION OF THE DRAWINGS Figure 1 shows schematically parts of a conventional GSM network. This network is essentially divided into a portion of central network 20 and an access portion 10. The elements of the central network illustrated in the Figure include the mobile switching centers or MSCs 202, the associated local location register HLR 201 and registration of VLR visitor location 204. The function and structure of these conventional GSM architecture elements are known to those skilled in the art and will not be described in more detail here. The core network also supports the General Packet Radio Service (GPRS), and for this purpose GPRS support nodes (SGSN) 203 are illustrated. Even if it is not illustrated in the figure, it will be understood by those with knowledge in the field that the central network portion may include access to other mobile and fixed line networks, such as, for example, ISDN and PSTN networks, data networks in packets and switched by circuit such as intranets, extranets, and internet through one or several gate nodes. The access portion consists essentially of base station subsystems BSS 10, one of which is illustrated in Figure 1, which communicate through defined interfaces A and Gb fixed standards with MSCs 202 and SGSNs 203, respectively in the network portion. 20. Each base detection subsystem BSS 10 includes a base station controller BSC 103 that communicates with one or more base transceiver stations BTS 101 through the defined air interface Abj.s 102. The transceiver stations of base 101 communicate with mobile terminals MT 1 on the GSM standard Um radio air interface. It will be understood that while BTS 101 and BSC 103 are illustrated as forming a single entity in BSS 10, the BSC 103 is frequently separated from the BTSs 101 and can even be located in the mobile services switching center MSC 202. The physical division illustrated in Figure 1 serves to distinguish between the parts of the network that make up the network portion of the network. access 10 and the parts of the network forming the core network portion 20. In addition to the standard access network portion provided by the BSS's 10, the network illustrated in Figure 1 further includes a modified access network portion 30 illustrated in the lower half of the figure. Next, it will be described as a portion of unlicensed radio access network 30. The components that make up this portion of unlicensed radio access network 30 also allow the mobile terminal 1 to access the GSM core network portion, and in this way, to other communication networks through an unlicensed radio interface X, represented in Figure 1 by the bidirectional arrow 31. By radio without a license we refer to any radio protocol that does not require the operator to use the mobile network has obtained a license from the appropriate regulatory entity. In general, such unlicensed radio technologies should be of low power and therefore of limited range compared to licensed mobile radio services. This means that the battery life of the mobile terminals will be longer. In addition, since the range is low, the unlicensed radio can be a broadband radio, thus offering better voice quality. The radio interface can use any unlicensed radio protocol such as a wireless LAN protocol or Digital Enhanced Wireless Telecommunications (DST). Preferably, however, a Bluetooth radio is used, which has a high bandwidth and lower power consumption than the conventional public mobile radio. The Bluetooth standard specifies a bidirectional digital radio link for short-range connections on two different devices. The devices are equipped with a transceiver that transmits and receives in a band of frequency of approximately 2.45 GHz. This band is available globally with certain variations of bandwidth according to the country. In addition to data, up to 3 voice channels are available. Each device has a unique 48-bit address of the IEEE 802 standard encryption and integrated verification are also available. The element of the fixed access network portion 30 adapted to communicate with the Bluetooth interface is designated as the home or home base station (HBS) 301. This element handles the radio link protocols with the mobile terminal MT 1 and contains transceivers radios defining a cell in a manner similar to the operation of a conventional GSM base station transceiver BTS 101. The local base station HBS 301 is controlled by a local base station controller HBSC 303, which communicates with a service switching center MSC 202 mobile phones through the GSM standard A interface and also with a GPRS service support node SGSN 203 via a standard Gb interface, if available in the central network portion. The interface between the local base station HBS 301 and its local base station controller HBSC 303 is designated as the Y interface. The local base station controller HBSC 303 provides the connection between the MSC 202 or SGSN 203 and the mobile terminal 1. The function The combination of the local base station HBS 301 and the local base station controller HBSC 303 emulates the BSS operation 10 towards an SGSN 203 and MSC 202. In other words, when viewed from the elements of the core network 20 such as the mobile services switching center (MSC) 202 and the serving GPRS support node (SGSN) 203, the fixed access network portion 30 comprised of the local base stations HBS 301 and the local base station controller HBSC 303 it resembles a portion of the conventional access network 10. The applications using the mobile terminal MTl on the public mobile network radio interfaces also operate on the Bluetooth radio between the mobile terminal 1 and the local base station HBS 301. The interface between the local base station HBS 301 and the local base station controller HBSC 303 which is designated Y in Figure 1 is preferably provided through a fixed link. The local base station 301 is contemplated to be a small device that a subscriber can acquire and install in a desired location such as at home or in an office to obtain fixed access to the mobile network. Nevertheless, can also be installed by operators in places of heavy traffic. To reduce installation costs by the operator, the interface between the local base station 301 and the local base station controller 303, which is designated as the Y interface in Figure 1, therefore preferably exploits an already existing connection provided by a fixed network 302. Preferably, this network is a broadband packet switched network. Suitable networks can include networks based on ADSL, Eternet, LMDS, or similar. Home connections to such networks are increasingly available to subscribers. Although not shown in Figure 1, the local base station HBS 301 will be connected to a network terminal that gives access to the fixed network 302, while the local base station controller HBSC 303 may be connected to an edge router ER of the network 302 that also connects the fixed network 302 with other networks such as intranets and the Internet. IP is used for communication between the HBS source base insert 301 and the local base station controller HBSC 303 in a fixed network 302 to make the data transport independent of the network type. The link between the local base station HBS 301 and the local base station controller HBSC 303 is preferably always open, such that this connection is always available without the need to reserve a channel, while the fixed network 302 is preferably a network based in IP, ATM-based networks could also be used. In particular, when using DSL technologies in this network, they could be used directly on the ATM layer, since they are based on ATM. Naturally, an ATM-based network could also be used to transport IP, serving as the base layer. The local base station HBS 301 is installed by plugging it into a port of a suitable modem, such as an ADSL or CATV modem, to access the fixed network 302. The port is in contact with an intranet or is bridged or good routing at the IP level. Thus, standard protocols such as IP DHCP, DNS and the like are used. The local base station HBS 301 connected to the modem uses these standard protocols and works to establish a connection with an HBSC source station controller 303. A registration procedure for a local base station 301 that connects for the first time or reconnects with a controller of Local base station HBSC 303 is described for example in European Patent Application Number EP-A-1 207 708.

The base stations 101 and 301 in both the conventional access network portion 10 and the unlicensed radio access network portion 30 define a coverage area illustrated in Figure 1 by hexagonal cells 104, 304. While the dimensions The relative coverage of these cells is not exact in the figure, however it is clear that the cell coverage of a conventional BTS 101 is much greater than the minicell generated by a local base station of comparatively low power HBS 301. A minicell will have a diameter of approximately 50 to 200m. For this reason, and since an HBS 301 can be installed in any place where there is a port for the fixed broadband network connected to an HBS 303, one or more mini-cells 304 generated by HBS's 301 can be located within the cells 104 of a conventional BTS 101. In a mobile network with conventional public license such as GSM, call transfer between adjacent cells is enabled by informing the currently connected access network 10 and the central network portion 20 of the identification of neighboring cells through a global CGI cell identity containing the mobile country code (MCC), mobile network code (MNC), cell identity (Cl) and Location Area Code (LAC). Information about which nodes, ie MSCs (or SGSN 203, if available on the network) and BSCs controlling these cells is also configured in the mobile core network, BSC 103 should be able to communicate the numbers of radio frequency channels Absolutes (ARFCN) assigned to all cells neighboring a mobile terminal 1 connected to it in such a way that the mobile terminal 1 can measure the associated frequencies and report back the strongest frequencies. In addition to the ARFCN channel number, this message also includes a base station entity code BSIC that is unique in the area of the base station transmitting on the identified channel frequency. With the introduction of a large number of mini-cells 304 resulting from the installation of an unlicensed radio access network 30, this type of operation and maintenance activity becomes very complex and time consuming, particularly since the location of the minicells can change with the passage of time. The mobile country code (MCC), mobile network code (MNC) and location area code contained in the global CGI cell identity jointly define a location area (LA) and are collectively known as the location area identifier (THE I) . The location area refers to a specific group of base station controllers BSCs and the associated base station transceivers BTS connected there. The GSM network is divided into several LA location areas, which are commonly geographically separated. A simplified logical structure of a GSM network showing the location areas is illustrated in Figure 2. Four location areas, LA1, LA2, LA3, and LA4 are illustrated in Figure 2. A mobile services switching center MSC 202 controls a LA location area. A visitor location recorder VLR 204 is also associated with each location area LA. All base station controllers BSCs 103 connected to this mobile services switching center MSC 202 are assigned to this location area LA. That is also true for all BTS 101 base station transceivers associated with each base station controller BSC 103, even though it is not illustrated in Figure 2 for reasons of clarity. While some mobile services switching centers MSC 202 can take care of more than one localization area LA, localization areas are not divided between mobile services switching centers MSC 202. Since the localization areas LA correspond generally to separate geographical areas , the junction between cells in different localization areas LA is limited and then only for cells between which a transfer is required. In this case, the cells 104 in an adjacent location area LA should be defined as neighboring cells in the mobile services switching center MSC 202 source and the base station controllers BSC 103 to allow the transfer. When an unlicensed access network is connected to the GSM network, a local HBSC base station controller 303 will be connected to a specific mobile services switching center 202 and can therefore be considered as part of the associated location area. However, unlike the fixed location of the base station transceivers BTS 101 of a public mobile network with conventional license, the location of the HBS originating base stations 301 connected to the local base station controller HBSC 303 can change constantly. Likewise, the number of HBS originating base stations 301 connected to the local base station controller 303 can also change constantly as new subscribers connect to the unlicensed radio access network. At any given time, therefore, the local base station controller HBSC 303 may be controlling HBS originating base stations 301 in very different locations, with neighboring cells in several different location areas. The problem therefore arises in the sense of how to assign identifiers, such as a global CGI cell identity, to each mini-cell 304 connected to the local base station controller, to which MSC 202 mobile station switching centers connect station controllers HBSC 303 local base, since these can control minicells 304 in very different geographic areas and finally how to define the location of minicells 304 in neighboring GSM cells 104 to allow a transfer since the minicells can be extended over many LA location areas and also they can change location. In accordance with a present invention, multiple local base station controllers HBSC 303 are provided, each of which is assigned to a mobile services switching center MSC 202 which controls a specific location area. HBSC originating base stations 301 are then distributed dynamically among the unlicensed radio access networks 30 such that each HBSC 303 local base station controller connected to a MSC 202 mobile services switching center controls only base stations of HBS origin 301 located in the required location area. This is illustrated schematically in Figure 3. In the arrangement shown in Figure 3, the division of the GSM network into geographical areas based on the concept of location area is preserved. Four location areas LA1 to LA4 are illustrated. In each of these areas, at least one unlicensed radio access network is provided through a local HBSC base station controller 303 that will be connected to multiple HBS source base stations (not illustrated) through a network of fixed access 302 (not illustrated). It is not necessary that each location area defined in a mobile network with a public license such as GSM have an unlicensed access network 30, however all unlicensed radio access networks must be assigned fixedly to a location area. Each access network has its own unique cell identifier valid for all minicells 304. A location area is part of this unique cell identifier. Accordingly, each local base station controller HBSC1 to HBSC4 303 defines its own unique location area; the local base station controller HBSC1 located in the location area LAl therefore defines a further location area LA70, the local base station controller HBSC2 located in the location area LA2 defines a further location area LA69, the station controller Local base HBSC3 located in the location area LA3 defines additional location area LA71 and the local base station controller HBSC4 located in the location area LA4 defines an additional location area LA72. In addition, all HBS originating base stations 301 connected to the local base station controllers HBSC1-HBSC4 have been specifically assigned to this local base station controller as a consequence of their current location. This is achieved by using an access point distribution function. In its simplest form, the access point distribution function 40 is a look-up table that can be accessed by a local base station HBS103 or alternatively by a local base station controller HBSC 303 to obtain the controller's IP address data. from local base station HBSC 303 to which a local base station could be connected. If the access point distribution function is to be accessed by the base stations of HBS origin 301, they should be provided in the fixed broadband network 302 and be accessible through a suitable request by the local base station HBS 301 when the latter it connects to the broadband network. The access network distribution mechanism is illustrated in Figure 4. Figure 4 shows two location areas LA1 and LA2. A first local base station controller HBSC 3031 is connected to the first of these location areas LAl and a second local base station controller HBSC2 303 is connected to the second location area LA2. A mobile station MS 10 is displayed in the vicinity of a local base station HBS 103 that has not yet been connected to a local base station controller HBSC 303. The numbered arrows shown in Figure 4 illustrate the various messages exchanged between the various elements for the base stations of HBS origin 301 to be assigned to a specific local base station controller HBSC 303, or more generally for unlicensed radio access points to be distributed to a radio access network without a specific license. The signaling sequence suggested by the arrows in Figure 4 is illustrated in Figure 5. In Figure 5, the various elements involved in signaling are shown at the top of the drawing. The mobile station MS is indicated twice on the sides of the figure. The mobile station MS on the left Um represents the GSM standard interface Um through which the mobile station communicates with a base station subsystem BSS 10 and the mobile station MS-X on the right represents the radio interface without a license, or interface X, of the same mobile station, through which the mobile station communicates with a local HBS base station. The function of distribution of access points? Func. It is understood, however, that this function may be available at the initial point of contact of the local base station HBS 301 with the fixed broadband access network 302 or alternatively it may be provided to Through a database server located in the fixed broadband access network 302 and accessible through a DNS request, it is considered that the mobile station is in the location area and it is moving in a cell GSM identified by a specific CGI cell identifier or is making an active call through the base station controller BSC 103 that controls this cell.The local base station HBS 301 is either a recently installed base station or one that has recently moved from another location and is connected to the broadband access network 302. As the mobile station moves in the mini-cell 304 cuber to the local base station 301, the local base station establishes a radio link with the mobile station MS 10 through the radio interface without license X as shown in event 1. In the event 2, the local base station 301 requests from the mobile station MS that the CGI cell identifier or location area identifier LA and the last GSM cell from which the mobile station is moving or is in contact. That is supplied by the mobile station MS. In the event 3, the local base station HBS 301 connects to the access point distribution function 40 and provides this function with the CGI cell identifier or location area LAl communicated by the mobile station MS. In response to this information, the access point distribution function checks the database to determine which HBSC base station controller 303 is handling the location area defined by the CGI cell identifier or location area identifier LAl. If a local base station controller HBSC 303 is identified for this location area, then the corresponding IP address data required by the local base station HBS 301 to establish a connection to the local base station controller HBSC 301 are transmitted back to the local base station HBS 301. If more than a local base station controller HBSC 303 is present in this location area, the information regarding one of them is returned to the local base station HBS 301. With this address data retrieved , the local base station HBS 301 is then registered in the local base station controller HBSC 303 allowing the establishment of a complete connection. The registration procedure allows the local base station controller HBSC 303 to update a data structure representing a logical view of all HBSC 303 source base stations connected to it. To a local base station HBS 301 an address is assigned an IP address in the fixed network 302. After registration, the transfer procedure may start or, alternatively, the mobile station may continue to travel through the mini cell in contact with the local base station controller. Since the minicells 304 generated by each local base station HBS 301 are so small in comparison to the GSM 104 cells or other radio mobile network with public license and the uplink signal strength within a minicell is low compared to what can be obtained in an adjacent GSM cell or that encompasses it 104, a mobile station MS 10 moving towards a cell 104 of an adjacent location area LA is preferably transferred to a GSM cell 104 of the same location area before to change location areas. Similarly, before entering a minicell of a new location area, a transfer between neighboring cells of the GSM network preferably occurs such that the mobile station is connected to the correct location area LA before being transferred to a mini cell 304. With this arrangement, the transfer of a cell 104 in the mobile network with public license or GSM network to a mini-cell 304 in the unlicensed radio access network 30 only requires that the HBSC cell identifier CGI be defined in the others elements of the same area of location. In other words, this CGI must be defined in the mobile services switching center MSC 202 to which the local base station controller 303 is connected as well as the base station controllers BSC 103 and base station transceivers BTS 101 also connected to this. mobile services switching center MSC 202. Similarly, for the transfer of an unlicensed radio access network 20, i.e., from a local HBSC 303 base station controller to a GSM cell, only the handled cell identifiers by base station controllers BSC 103 connected to the same mobile services switching center MSC 202 that the local base station controller HBSC 303 should be defined as neighboring cells in the unlicensed radio access network 30 of this local base station controller HBSC 303 As well as in the MSC 202 mobile services switching center. Alternatively, no information about neighboring cells has to be configured in the radio access network without a license. On the contrary, a mobile station MS will report the cell identifier of a CGI neighbor cell identifier dynamically to the HBSC, and then activate the Transfer to this cell. This greatly reduces the installation activities required to allow the transfer when the publicly licensed mobile network is extended using unlicensed radio access networks 30. In accordance with an alternative arrangement, each local HBS 301 base station could be assigned to a default local base station controller HBSC 303. Thus, when a local base station is moved and reinstalled or reinitialized, the initial connection made with the access network would be within this local base station controller HBSC 303, but the local base station HBS would subsequently be redirected to a new local base station controller HBSC 303 when traveling in a mini cell in the associated location area. One advantage of such an arrangement is that the default local base station controller HBSC 303 could invoke the access point distribution function 40 in response to a request from the local base station containing a researched cell identifier or area identifier. location. In other words, in event 2 shown in Figure 5, the CGI cell identifier or location area identifier LAl of the last GSM cell that came into contact is supplied to the default local base station controller 303. This controller of local base station 303 then invokes the access point distribution function by investigating the database server and returns the address of the local base station controller HBSC 303"closest" to the mobile station MS. To avoid congestion, the function and distribution of access points 40 is available in several database servers that are located throughout the network and specific to each operator. The mobile country code MCC and the mobile network code MNC contained in the global cell identity CGI can then be used to construct a DNS request addressed to an operator-specific database server. Once the address of the database server is retrieved, it can be saved to the local base station HBS 301. The database server location would then not be necessary unless it was activated by the network operation and maintenance system. or by the end user, for example, the local base station HBS is reinitialized to the factory defaults. Preferably, the location area identity portion LA1 of the CGI global cell identity and the local base station controller information retrieved with this indicator could also be retained at the local base station to decrease the load to the database server . In this way, in case of a power supply suspension or if the local HBS base station has to be reinitialized, this information can be retrieved without having to make an additional request. A cache memory could also allow limited storage of mapping for the last few areas of location. This would be useful when a local HBS base station is sowed out of the origin frequency but always returns to the same location area afterwards. If a local HBS base station 301 is used in an area where there is no mobile network coverage with public license, the mobile station MS 10 should indicate this fact to the local base station HBS 301 and at the same time send the last global identity of received CGI cell or location area identifier LAl. The local base station HBS could then use the MCC mobile country code portions and the MNC mobile network code of the cell global identity to locate a database server and access the access point distribution function. In this case, the request to the database server would contain some type of local base station identification together with the global CGI cell identity of the last known mobile network cell. Based on this modified request, the database server would return a source database controller information in accordance with a modified mapping. For example, it could be a static assignment based on the originating base station identifier. Alternatively, a local HBSC 303 default base station controller could be assigned to all HBS originating base stations in an area where there is no mobile network coverage with a public license. The overhead installation costs required for the transfer can be further reduced when the entire unlicensed radio access network is defined by a single global CGI cell identifier. This is illustrated in Figure 6. This figure schematically shows an unlicensed radio access network as illustrated in Figure 1 with the core network portion 20 illustrated in the same manner in Figure 1. The same reference numbers have been used for the same parts in both Figures, in such a way that a renewed description of these will not be repeated. In the unlicensed radio access network 30, the local base station controller HBSC 303 controls several base stations of HBS origin 301. This is shown as an example in Figure 6 through the illustration of 3 HBS 301. With the object of identifying the mini cells 304 to allow a transfer, instead of assigning a unique cell identifier, the base station identifier and the frequency channel number for each mini cell 304, all the mini cells 304 in the same radio access network without licenses are identified for the GSM network through the same identification. In fact, the entire unlicensed radio access network 30 or rather the local base station control HBSC 203 that controls this access network is assigned a single cell identification. This identification is then distributed on the network by manual operation and maintenance procedures upon installation, such that the central network portion and the relevant base station subsystems BSS 10 controlling neighboring cells or several mini-cells can access this identification. The cell identification is equivalent to the global identification of CGI cell used in a conventional GSM network and also includes a unique location area assigned to the entire access network 30. This is illustrated schematically in Figure 6 through the assignment to the local base station controller 303 of a CGI-A cell identifier. In addition to the CGI cell identifier, the unlicensed radio access network has a single base station identifier BSIC and an absolute radio frequency channel number ARFCN. The base station identifier BSIC and the absolute radio frequency channel number ARFCN are communicated by each local base station HBS 301 in response to a measurement report request for the mobile station MS 1 and therefore an indication of these identifiers will be included in any measurement report sent by a mobile station 1 to its connected base station controller 103 when a connection is established with a local base station HBS 301 of an unlicensed radio access network 30. This naturally implies that the number of The absolute radio channel ARFCN of the unlicensed radio access network is included in the list of measurements sent by the base station subsystem BSS 10 connected to the mobile station 1. The combination of the base station identifier BSIC and the absolute number of ARFCN radio frequency channel should therefore serve to indicate the specific cell identifier fico CGI assigned to the radio access network unlicensed 30. If multiple access networks unlicensed radio are present, each will have a single associated cell identifier CGI and therefore a single combination of base station identifier BSIC and absolute number of radio frequency channel ARFCN. When installing the unlicensed radio access network, the unique CGI cell identifier is communicated to all base station subsystems BSS 10. These elements will also be informed of the associated base station identification code BSIC and the absolute number of the base station. ARFCN radio frequency channel. This allows the base station subsystem BSS 10 to include the frequency emitted by the neighboring local base station in the list of frequencies communicated to a mobile station within its own cell 104 to be measured and reported to determine if transfer is required and to what cell. The MSC 202 and / or GPRS mobile services switching centers support SGSN nodes 203 which will also be informed of the unique cell identifier. The unlicensed radio access network 30 described with reference to the figures resembles a conventional access network insofar as there are several base station elements with their own functionality and a controller connected to these base stations. However, the present invention is not limited to this structure. In an alternative mode, the same operation is achieved with an essentially transparent access point which is an existing access point to a broadband network, by transferring the functionality of the home base stations to the home base controller, the mobile station or both. In other words, the mobile station communicates directly with the local base station controller HBSC 303 through an unlicensed radio interface and the broadband network through the access point. As for signaling, that would mean that messages within the mobile station MS and the local HBS base station and all its messages between the local HBS base station and the HBSC origin base session controller would be transported directly between the station controller mobile and the local base station controller. The local HBS base station therefore serves simply as a transparent access point. The mobile station will request and be assigned the local base station controller address information. In the same way, the mobile station MS should have a certain form of cache mechanism that allows the storage of a limited number of mappings between the global CGI cell identities and the address information of the associated HBSC local base station controllers recovered before . The detailed description above of the cell administration refers only to GSM networks as a conventional public mobile network. It will be understood by those skilled in the art, however, that the above description also applies to other conventional public mobile networks, such as UMTS or CDMA 2000.

Claims (16)

1. CLAIMS 1. A mobile telecommunication network that includes several base station systems (10) adapted to communicate with a mobile terminal (1) on a radio interface with predetermined license and switching centers (202) connected to several base station systems (10), wherein each switching center (202) and the base station systems (10) connected there share a location area identity, said base station systems (10) are adapted to communicate information indicating said area identity, location to a mobile terminal (1), characterized in that said network further includes at least two unlicensed radio access networks, each comprising a controller of access point (303) connected to one of said switching centers (202), multiple access points (303) adapted to communicate with said mobile terminal (1) through an unlicensed radio interface, a fixed broadband network (302) ) connecting said various access points (301) with said access network controllers (303) and a look-up table mapping a location area identity with address information for an access point controller (303) in said fixed broadband network (302) wherein each of said access points is adapted to receive from said mobile station information indicating the last location area received to receive address information from said search table for an access point controller (303) mapped to said location identity and to establish a connection with said addressee access point controller (303) through said fixed broadband network. A network according to claim 1, characterized in that said search table (40) is accessible through said fixed broadband network (302) and is adapted to generate said address information in response to a request which includes said location identity. A network according to claim 1 or according to claim 2, characterized in that said access point is adapted to generate a request to said search table containing said location identity and to receive said information from address in response to said request. A network according to claim 1 or according to claim 2, characterized in that said access point is connected to an access point controller (303) and is adapted to transmit said location identity to said controller from access point (303) said access point controller (303) is adapted to present a request to said search table containing said location identity, to receive said address information in response to said request and to transmit said address information to said point of access (301). 5. A network according to claim 1, characterized in that at least a part of said search table (40) is stored in said access point. 6. A network according to claim 1, characterized in that at least a part of said search table (40) is stored in an access point controller (303) connected by default to said access point (301) . 7. A network according to any of the preceding claims, characterized in that said fixed broadband network is a network based on Internet protocol and said address is an Internet protocol address. 8. An unlicensed radio access system connected to a central network portion of a licensed mobile network, said unlicensed radio access system includes several access points (301) adapted to communicate with mobile stations (1) to through an unlicensed radio interface, several access point controllers (303) connected to said centered network portion (20) and a fixed broadband network (302) connected to said access points (301) and connected to said access point controllers (303), characterized in that each access point controller (303) is associated with a location area in said licensed radio mobile network, said system is further equipped with at least one look-up table containing information on mapping location areas for sending information from access point controllers (303) in said fixed broadband network (302), wherein each access point (301) is adapted for receiving from a mobile station information indicating a location area corresponding to a portion of said licensed mobile network, to obtain from said search table address information of an access point controller (303) in said web network fixed broad (302) associated with said location network information and to establish a connection with said directed access point controller (303) through said fixed broadband network. 9. A system according to claim 8 characterized in that said search table is located in a database server located in said fixed broadband network (302). A system according to claim 8 or according to claim 9, further characterized in that at least a part of the data in said search table is stored in said access points. 11. A system according to any of claims 8 to 10, characterized in that said fixed broadband network is a network based on Internet protocol and said address is an Internet protocol address. 12. A system according to claim 8, characterized in that each access point (301) is connected for communication with a default access point controller (303) wherein the access points are adapted to connect to an access point. controller of different access points (303) if the indicator information of a location area does not correspond to the fixed broadband network address of said default access point controller (303). 13. A method for establishing a connection between a mobile station and a central network portion of a mobile communication network through an unlicensed radio access network, said mobile communication network comprising access portions including base stations ( 10) and switching control parts (202) connected to said base stations, each switching control part (202) shares a common location area identity with several of these base stations and said base stations (101) are adapted to communicating said location area identity to a mobile station, said unlicensed radio access network (30) comprises at least one access point (103) adapted to communicate with the mobile station (1) through a radio interface without a license, at least one access network controller (303) each connected to a switching control part (202), a fixed broadband network (302) connected to said at least one access point controller (303) and access point (103) and a look-up table containing data mapping a location area identity with an address of one of said access network controllers (303) in said network of fixed broadband (202), said method includes the steps of: said access point (301) receives from said mobile station information indicating a location area identity, receives from said search table the address of a point controller access (303) associated with said location area identity, establishes a connection with said recipient access point controller through said fixed broadband network to allow communication between said mobile station and said central network. A method according to claim 13, characterized by the additional step of: said access point presents a request to said search table (40) in said fixed broadband network (302), said request contains said information indicating said identity of location area. 15. A method according to claim 13, characterized in that each access point is connected for communication to a default access point controller (303), said method includes the step of: said access point controller for omission (303) receives from said access point said information indicating a location area identity, submitting a request to said search table using said location area identity information, receiving from said search table the address of a controller of access point (303) associated with said identity of location area and passing this address to said access point (301). 16. A method in an unlicensed radio access network for assigning and connecting access points (301) to an access point controller (303), said unlicensed radio access network includes several access points (301) , several access controllers (303) connected to a licensed mobile central network (20) and a fixed broadband network connected to said access controllers and to connect said access points and to connect said access points, and where each access point controller is associated with a location area of said licensed mobile network, said method includes the steps of: receiving from said mobile station a location area indicator indicating a location area of said mobile network with license with which said mobile station was in communication for the last time, retrieving fixed broadband network address information for an access point switching controller associated with said indi location area controller, and connecting said access point to said broadband network address retrieved from said access point switching controller to establish a connection.