WO2001045446A1

WO2001045446A1 - Selection of radiocommunication networks for a multimode terminal

Info

Publication number: WO2001045446A1
Application number: PCT/FR2000/003338
Authority: WO
Inventors: Jacques Palicot; Christian Roland
Original assignee: France Telecom; Telediffusion De France
Priority date: 1999-12-14
Filing date: 2000-11-29
Publication date: 2001-06-21
Also published as: FR2802379B1; EP1238557A1; JP2003517803A; FR2802379A1

Abstract

Detection occurs in a terminal, which is at least a receive terminal (TM ), of the region where the terminal is localized. At least one of the accessible networks (RT,RD) in said region is subsequently selected, since the radiocommunication network lists are pre-stored. One of several radiocommunication processing means included in the terminal and being compatible with the selected accessible network is activated. The terminal is thus adapted to radiocommunication networks according to the localization thereof.

Description

SELECTION OF RADIOCOMMUNICATION NETWORKS FORUN

MULTIMODE TERMINAL

The present invention relates to radio reception terminals at least of third generation whether they are in particular mobile radio terminals or not, audio or video receivers, or even a multimedia terminal. It relates more particularly to the optimization of radioelectric resources made available to the terminal depending on the geographic location where the terminal is located.

Furthermore, it is known that a location system, such as the GPS (Global Positioning System), will have to be included in new mobile radiotelephone terminals, in particular American ones, including a CDMA (Code Division Multiple Access) type radio interface for the purposes of localization and synchronization.

The present invention aims to adapt a terminal at least receiver to radio communication networks depending on the location of the terminal.

To this end, according to the invention, the method for selecting radio networks implemented in a receiving terminal in which characteristics of radio networks have been recorded beforehand, is characterized by the following steps:

- geographically locate the terminal by a location means included in the terminal providing the geographic coordinates of the terminal so that a geographic region where the terminal is determined based on geographic coordinates,

- select at least one network from a previously saved list of accessible networks in the geographic location of the terminal, and

- activate at least one of several radiocommunication processing means included in the terminal and compatible with the selected accessible network.

Thanks to the location means included in the terminal providing periodically, or on demand, the geographic coordinates of the terminal, the terminal knows the accessible communication networks through which it is able to communicate in the region where it is located.

At the recording stage, the lists of radiocommunication networks are previously downloaded into a reprogrammable non-volatile memory of the terminal which can be included in a removable integrated circuit module. This download can be carried out by any means, including by receiving a list of regional networks broadcast periodically through a broadcast network or transmitted by any other telecommunications network, for example giving access to a network list server, or again by conventional local loading of a microcontroller card.

In practice, the user of the receiving or receiving / transmitting terminal can only access the radiocommunication networks authorized by their subscription profiles. In this case, a list of authorized radiocommunication networks is stored in advance in the terminal, and the networks of Authorized radiocommunications are searched among the accessible radiocommunication networks in the terminal location region in order to select one of the accessible and authorized radiocommunication networks as the selected accessible network.

The selection of a radiocommunication network from the accessible networks can depend on a manual selection among types or categories of radiocommunication network, and / or of an automatic selection according to an order of priority, and / or the cost of radiocommunication, and / or the rate of radiocommunication.

The select steps, or the locate and select steps, can be performed again when the selected radio network is unavailable, or when the terminal goes outside the radio coverage of the selected radio network. According to other characteristics of the invention, the terminal can include a non-volatile memory addressable by means of locating the terminal as a function of an address of the geographic region of location of the terminal for storing the lists of radiocommunication networks by region. geographic, and an access authorization means containing a list of authorized radiocommunication networks through which only the terminal is authorized to communicate, so that one of the accessible radiocommunication networks is selected from said list of authorized radiocommunication networks . The non-volatile memory and the access authorization means can be included in a removable module of the terminal which is personal to a user, such as a SIM card for a terminal. radiotelephone.

According to another preferred embodiment, the radiocommunication processing means respectively compatible with radiocommunication networks are individually removable from the terminal, the activated radiocommunication processing means being preferably introduced into the terminal when the name of the selected accessible network is indicated by the terminal. This characteristic contributes to reducing the weight and the volume of the terminal. After introduction, the selected processing means can receive frequency and protocol characteristics of the selected network, provided by the terminal. The invention thus also relates to a terminal implementing the method of the invention.

Other characteristics and advantages of the present invention will appear more clearly on reading the following description of several preferred embodiments of the invention with reference to the corresponding appended drawings in which:

- Figure 1 is a partial schematic block diagram of a multimedia multimode terminal according to the invention;

- Figure 2 is a frequency distribution diagram for three geographic regions;

FIG. 3 is an algorithm of the method for selecting radio networks according to the invention; and FIG. 4 is a graph illustrating an example of a selection of radiocommunication networks in a mobile radiotelephone terminal according to the invention. Reference is made hereinafter to a multimode multimedia terminal TM shown diagrammatically in FIG. 1. The terminal TM is capable in particular of participating in radiocommunications with any type of telephone or radiotelephone terminal through RT radiotelephony networks and broadcast networks. RD data broadcasting for example radio programs and / or television programs. However, the invention is not limited to this type of multimedia terminal and relates to any radio receiver terminal capable of communicating through at least two of the radiotelephony and broadcasting networks.

The multimode multimedia terminal TM is organized around a microprocessor PR and includes an IRL-LOC means for geographically locating the terminal and 1RS radioelectric interfaces. The microprocessor PR conventionally comprises a central processing unit CPU with data memories and a ROM memory containing an operating system, and may for example be a DSP (Digital Signal Processor) processor. The processor PR is conventionally associated with a non-volatile memory EEPROM containing programs and particularly applications relating to radiocommunications through the RT and RD networks with which the terminal is capable of communicating. The processor PR is also associated through an input / output interface ES with an access authorization circuit AA and in particular with other peripherals such as an AF display which can be a large screen, a keyboard CL which can be analogous to a radiotelephone or microcomputer keyboard, to a MOD modem, etc. The means for geographically locating the terminal comprises an IRL location radio interface connected to a LOC location circuit. Typically, the LOC location circuit is constituted by a computer calculating coordinates of the place where the terminal TM is located, that is to say the longitude X and the latitude Y of the terminal, in accordance with the GPS positioning system ( Global Positioning System). The IRL interface is a GPS type interface capable of receiving the two frequencies at approximately 1.2 GHz and 1.5 GHz emitted by the twenty-four satellites of the GPS system so that the LOC location circuit determines the position with great precision. of the TM terminal in relation to four satellites of the GPS system, either on manual or automatic request, or periodically, typically every hundred milliseconds or approximately every second, or at longer time intervals, typically every minute to decrease the terminal's power consumption.

According to other variants, the means for geographically locating the terminal TM comprises a set of location calculators and a location interface adapted to receive location messages from at least three transmitting stations in order to deduce the geographic coordinates X by triangulation. and Y of the TM terminal. For example, the transmitting stations may be base stations of a radiotelephony network in the areas of coverage of which the terminal is at a given time, or else transmitting stations of a radiolocation or radio navigation system.

The PR processor is also connected to a EEPROM reprogrammable non-volatile memory containing a table of lists of TRC radio networks. These lists contain frequency and protocol characteristics of RT and / or RD radiocommunication networks with which the TM terminal can communicate. The TRC table corresponds to each of these radiocommunication networks a geographic address, for example a geographic area in a country, or a country, or a "continental" region such as Europe, Asia or North America. . The localization circuit LOC produces a place address AL corresponding to the zone, or to the country, or to the region where the terminal TM is located, as a function of the calculated geographical coordinates X and Y in order to select in the table TRC the networks of RC communication available at the AL address location where the TM terminal is located. Naturally, the geographical zones are defined arbitrarily, independently of the limits of coverage of the radiotelephony networks.

The memory, also designated by TRC in FIG. 1, in which the table TRC is contained is programmable, that is to say is downloadable on the one hand when the terminal TM is put into operation according to its applications and mobility, on the other hand for updating according to changes in the frequency and / or protocol characteristics of already registered radio networks and / or for recording the frequency and protocol characteristics of new radio networks. The downloading of a list of networks into the TRC table can be carried out either conventionally by local electrical or radiotelephone link with the TRC memory from a local server of a radiocommunication service provider, or from the manufacturer of the terminal TM, or from a list of networks server connected to the terminal TM through a periodic broadcasting network of list of networks on a predetermined frequency or through the fixed network of one of the RT radiotelephony networks, for example through a switch in the mobile service MSC of a GSM type radiotelephone network which is linked to a switching network by packet of data with management of mobility and access by radio GPRS (General Pac and Radio Service) which allows the broadcast of data in packets from a server to several mobile radiotelephone terminals.

The download can also be carried out at the home of the user owning the TM terminal by connecting it to a user's telephone line directly, or through a local radiocommunication base according to the DECT (Digital Enhanced Cordless Telephone) standard or a analogous standard.

By way of example, the table of TRC radiocommunication networks contains at least in part the frequency distribution plan shown in FIG. 2 which matches a place address AL which may belong to one of three "continental" regions such that an RI region corresponding to Europe, an R2 region corresponding to Asia and an R3 region corresponding to North America, to several RC radiocommunication networks, such as RT radiotelephony networks and broadcasting networks RD, with the frequency characteristics thereof. The various radio networks shown in Figure 1 can be classified in the following four categories Cl to C4:

- Cl: local or neighborhood radiotelephony networks CT2 (Cordless Telephone Digital), DECT (Digital Enhanced Cordless Telephone), PHS (Personal Handyphone System) and RLAN (Radio Local Area Network), BlueTooth, or HYPERLAN;

- C2: cellular radiotelephony networks GSM (Global System for Mobile communications), DCS 1800 (Digital Cellular System), PDC (Personal Digital Cellular), IS 95 (Intermediate Standard), D-AMPS (Advanced Mobile Phone System) digital to " spread spectrum "CDMA (Code Division Multiple Access), and UMTS (Universal Mobile Telecommunications System) corresponding to the international acronym IMT-2000 (International Mobile Telecommunications);

C3: non-geostationary low-orbit MSS (Mobile Satellite System) satellite radio networks, for example of the IRIDIUM or GLOBALSTAR type; and

- C4: digital broadcasting networks to broadcast radio programs according to the DAB standard (Digital Audio Broadcasting) and television programs according to the DVB standard (Digital Video Broadcasting), in particular according to the MPEG-2 standard (Moving Pictures Expert Group).

Although the geographical location of the terminal to be considered at a region "mainland" in Figure 1, the geographical location of the terminal by 1 ^• invention can also be determined with respect to groups of countries such as the European Economic Community EEC , compared to a country such as France, or compared to the coverage area of a radiocommunication network antenna, or more generally compared to the whole earth.

The block 1RS in FIG. 1 comprises radioelectric interfaces respectively compatible radioelectrically with the various radiocommunication networks through which the terminal TM can communicate; some of these radio interfaces may be common to several radiocommunication networks, particularly to several radiotelephony networks having neighboring useful frequency bands. Typically, a 1RS radio interface for reception comprises an antenna, one or more frequency transposition circuits, an analog-digital converter and a demodulator. When the radio interface also transmits radiocommunication signals, it further comprises a digital-analog converter, a modulator, one or more frequency transposition circuits and a duplexer of transmission and reception channels connected to the antenna. . Each of the 1RS radio interfaces is connected to a respective one of CD coding-decoding circuits adapted to the signals supported by the corresponding radiocommunication network. For example, when a coding-decoding circuit relates to a RT radiotelephony network, this is a speech coding-decoding circuit connected to a microphone and to a loudspeaker of the terminal; when the coding-decoding circuit relates to a broadcasting network RD, this is a digital circuit connected to at least one loudspeaker or to a screen for coding and decoding data packets according to the DAB standard or the standard DVB.

As a variant, each assembly comprising a 1RS radio interface and an encoding-decoding circuit CD relating to a respective radiocommunication network, as well as a microcontroller controlling these and connectable to the processor PR is included in a removable interchangeable module, pluggable into the terminal TM. Depending on the radio network selected by the PR processor or by the user, whose name is signaled by the terminal, for example by presenting it on the AF display as will be detailed later, the user entered in the terminal TM the IRS-CD module compatible with the selected network.

The access authorization circuit AA contains addresses, preferably corresponding to names, of the radiocommunication networks to which the user of the terminal TM can have access according to subscriptions that he has subscribed. As will be seen in the method of the invention, among the accessible RC radiocommunication networks chosen automatically in the table TRC as a function of the terminal location address AL, the processor PR eliminates the selection of all the accessible networks whose addresses cannot be read in the AA circuit in correspondence with an access authorization.

According to a preferred embodiment, the access authorization circuit AA is a removable module of the integrated circuit card type, also called a smart card, like a SIM (Subscriber Identity Module) card removable from a mobile radiotelephone terminal. In this embodiment, the circuit AA comprises a microcontroller with a reprogrammable non-volatile memory EEPROM which contains in particular all the characteristics of the subscription profiles of the user relating to the networks of authorized radiocommunication RC (RT and / or RD) likely to be accessible by the terminal TM during its mobility, as well as a table matching these subscription profiles with the addresses of the authorized radiocommunication networks. The EEPROM memory in the access circuit AA also includes programs relating to the authentication of authorized radiocommunication networks and to applications related to these networks. As a variant, the EEPROM memory includes the content of the table of TRC radio networks in place of the TRC memory illustrated in the terminal TM. For this variant, the downloading in particular for updating the table TRC is carried out directly in the removable module constituting the access authorization circuit AA. The update can also be carried out by an exchange of the AA module.

With reference to FIG. 3, the method for selecting radio networks for the multimode receiver TM comprises main steps EO to E10.

Initially, before any operation of the terminal TM, a step EO downloads lists of radiocommunication networks RT, RD, one per geographical region with a classification by category. Each list contains the frequency and protocol characteristics of radiocommunication networks which cover at least partially one respective of several regions, for example the regions RI to R3 according to the frequency distribution plan shown in Figure 2. It is also assumed that the circuit AA has previously memorized a list of authorized radio communications.

After putting the TM terminal into operation by pressing an ON / OFF button and very often followed by the validation of a confidential code composed by the CL keyboard, the LOC location circuit geographically locates the TM terminal in determining its geographic coordinates such as longitude X and latitude Y in order to deduce therefrom the place address AL of the geographic region where the terminal is located in step E2.

Depending on the location address AL, in step E3, the processor PR searches the lists in the table TRC for the list of radiocommunication networks RC accessible in the region where the terminal TM is located, which list is designated by the AL address. If the region designated by the address AL does not contain any accessible radiocommunication network, the method returns to step E2 to trigger another location of the terminal TM if this is not periodic.

Otherwise, the memory TRC communicates to the processor PR the list of radiocommunication networks RC accessible in the region designated by the address AL. The list of accessible radiocommunication networks can be made up in a tree-like manner from several lists, by taking from the table TRC for example the designations of the networks accessible locally, then of the networks accessible throughout the country where the terminal is located, networks accessible throughout the continent where the terminal is located, and finally networks covering the entire earth. The processor PR searches in 1 • next step E4 in the access authorization circuit AA for the radiocommunication networks which are authorized according to the terminal user subscriber profiles, among the radio networks accessible in the terminal location region and indicated by the TRC memory. If no accessible radiocommunication network is authorized by the circuit AA, the method returns to step E2 to trigger another location of the terminal TM if this is not periodic. Otherwise, the access authorization circuit AA provides the processor PR with a list of the addresses, such as names, of the radio communication networks which are accessible and authorized.

If in the next step E5 the user does not wish to manually select a network from among the accessible and authorized radiocommunication networks, the process continues in step E6 so that the processor PR selects one of the accessible radiocommunication networks and allowed based on at least one of the following four criteria. According to a first criterion, the processor PR invites the user by means of, for example, the AF display and an elevator key to select the type of radiotelephony network RT or broadcasting RD, this selection being validated by the request. a key on the CL keyboard; the processor PR then automatically selects one of the accessible and authorized networks according to the type chosen RT or RD according to one of the second, third and fourth criteria below.

According to the second criterion, a radiocommunication network is selected according to an order of priority which can for example depend on the frequency band of the network; for example, the radio network offering the frequency band the highest is selected first.

According to the third criterion, the selection of an accessible and authorized radiocommunication network depends on the comparison of the average radiocommunication costs in the accessible and authorized networks. For example, if a radiotelephone network belonging to category C1 (CT2, PHS, DECT, PHS, RLAN, HYPERLAN) and a radiotelephone network belonging to category C2 (GSM, DCS 1800, UMTS, PDC, AMPS, etc. ) are accessible and authorized networks, it is preferable to select one of these two networks offering the lowest radiocommunication cost.

According to the fourth criterion, a radiocommunication network is selected from the accessible and authorized networks as a function of the radiocommunication rates offered by these. For example, when the terminal TM is intended to receive data often, it is advantageous that these are communicated as quickly as possible so that the communication is as short as possible; in this case, the processor PR chooses the radiocommunication network offering the highest bit rate among the accessible and authorized networks. Returning to step E5, if the manual selection is chosen by the user, the processor PR controls the presentation of the names of the radiocommunication networks accessible and authorized in the AF display unit by displaying there the names of the networks arranged by type of network and by category, for example in step E51. Then the user selects and validates a radio communication network using the keyboard CL in step E52.

Alternatively, the display and selection by keyboard can be replaced or supplemented by voice messages and voice commands in the TM terminal.

After step E6 or E52, the processor PR knows the radio communication network RC accessible, authorized and selected and reads the frequency and protocol characteristics of this network selected from the memory TRC. In step E7, the processor PR selects and activates 1 • radio interface 1RS and the coding-decoding circuit CD which are compatible with the radio network selected in order to control them as a function of the frequency and protocol characteristics corresponding to the selected network read in the TRC memory. According to the variant already presented, instead of the processor PR controlling the communications in the terminal TM relating to the selected radiocommunication network, the processor PR communicates the frequency and protocol characteristics corresponding to the selected network read from the memory TRC, to a microcontroller which is included with 1 • 1RS radio interface and to the CD coding / decoding circuit in a module compatible with the selected radio network. Step E7 ends with the display of the name of the network selected on the AF display. The module compatible with the selected accessible network is introduced into the terminal in 1 • step E7 as a function of the name of the selected network indicated by the AF display or by a voice message broadcast by the terminal.

In the next step E8, the processor PR verifies that the radio network selected for a given type of service is available to establish a call or simply receive data in the terminal TM. If the selected network is unavailable, the method returns to step E4 to select another radiocommunication network from the authorized and accessible radiocommunication networks in the location region of the terminal. As a variant, when the selected network is unavailable in step E8, the method goes to step E2 in order to relocate the terminal which may have changed geographical region since the last location. If the selected network is available in step E8, the processor PR can propose to the user on the display AF a change of network selected in step E9; if the selected network must be changed, the method also returns to step E4.

Finally in step E10, the processor PR signals to the user on the display AF a loss of radioelectric coverage of the selected radiocommunication network when the terminal TM passes from an area covered radioelectrically by the selected network to an area not covered radio by the selected network. If the terminal passes outside the radio coverage of the selected network, the method goes from step E10 to step E4 for a slow moving mobile, or more generally to step E2 so as to locate the TM terminal in a region, insofar as the location performed by the LOC location circuit is not periodic. On the other hand, if the determination of the geographic coordinates X and Y of the place where the terminal TM is located is periodic, the method goes directly from step ElO to step E3 to search again for a list of accessible radiocommunication networks. By way of example, it is assumed with reference to FIG. 4, that the LOC location circuit has determined geographic coordinates X and Y corresponding to the location of the terminal TM in the city of Rennes, capital of the region of Brittany having for ALB terminal location address. The terminal TM is supposed to have a radiotelephone function and a radio program listening function and is connected to a microcomputer PC to receive and transmit data. Furthermore, it is assumed that the memory TRC has recorded the frequency and protocol characteristics of twelve radiocommunication networks which are accessible in various regions on earth, and the access authorization circuit AA in the terminal TM has not recorded than seven names of authorized radiocommunication networks according to the subscription profiles of the user. It is assumed that the user of the terminal TM simply wishes to listen to a radio program, for example through the DAB broadcasting network, while being able to communicate with a remote interlocutor through a radiotelephony network. First of all, at a step E5, the user imposes the choice of the broadcasting network DAB so that at a next step E7 the processor PR selects and activates the radio interface IRS2 and the coding-decoding circuit CD2 corresponding to the DAB network. Then at other steps E5 and E6, the user leaves it to the processor PR to select one authorized from the five accessible radiotelephony networks RC for the address ALB which offers, according to said third criterion, the lowest communication cost if the radio communication concerns speech, or which offers according to said fourth criterion the highest bit rate if the radiocommunication relates to data. The processor PR then selects and activates the radio interface IRS1 and the coding-decoding circuit CD1 corresponding to the accessible, authorized and selected radiocommunication network. Thus, according to this example, two radiocommunication networks DAB and RC are selected and two radiocommunication processing means IRS2-CD2 and IRS1-CD1 included in the terminal TM and compatible with the selected accessible networks are activated.

Claims

1 - Method for selecting radio networks implemented in a receiver terminal (TM) in which characteristics of radio networks (RT, RD) have been previously recorded (EO), characterized by the following steps:

- geographically locate (E2) the terminal (TM) by a localization means (1RS, LOC) included in the terminal (TM) providing the geographic coordinates of the terminal (TM) so that a geographic region (X, Y, AL) where the terminal is located is determined based on geographic coordinates,

- select (E3 to E6) at least one network (RC) from a previously recorded list of networks accessible in the geographic location of the terminal, and - activate (E7) at least one of several radiocommunication processing means ( 1RS, CD) included in the terminal (TM) and compatible with the selected accessible network (RC).

2 - Method according to claim 1, according to which the step of recording (E0) consists in downloading lists of radiocommunication networks in a reprogrammable non-volatile memory (TRC) of the terminal.

3 - Process according to claim 1 or 2, comprising the steps of:

- store beforehand (E1) a list of authorized radiocommunication networks, and - search (E4) the networks of radiocommunication authorized among the radiocommunication networks (RC) accessible in the location region of the terminal in order to select (E6; E51) one of the accessible radiocommunication networks and authorized as the selected accessible network.

4 - Method according to any one of claims 1 to 3, according to which the selection of a radiocommunication network from the accessible networks depends on a manual selection (E52) among types (RT, RD) or categories of radiocommunication network, and / or an automatic selection according to an order of priority, and / or the cost of radiocommunication, and / or the rate of radiocommunication.

5 - Method according to any one of claims 1 to 4, according to which the steps of selecting (E3 to E6), or the steps of locating and selecting (E2 to E6), are again carried out when the selected radio network is unavailable, or when the terminal (TM) goes outside the radio coverage of the selected radio network.

6 - Method according to any one of claims 1 to 5, according to which the terminal (TM) comprises a non-volatile memory (TRC) addressable by terminal location means (1RS, LOC) as a function of an address ( AL) of the geographic region of the terminal location to store the lists of radiocommunication networks by geographic region (RI, R2, R3). 7 - Process according to claim 6, according to which the terminal (TM) comprises an access authorization means (AA) containing a list of authorized radiocommunication networks through which only the terminal is authorized to communicate, so that the 'one of the accessible radiocommunication networks (RC) is selected from said list of authorized radiocommunication networks.

8 - Process according to claims 6 and 7, according to which the non-volatile memory (TRC) and the access authorization means (AA) are included in a removable module of the terminal (TM).

9 - Method according to any one of claims l to 8, according to which the radiocommunication processing means (1RS, CD) respectively compatible with radiocommunication networks are individually removable from the terminal, the activated radiocommunication processing means being preference entered in the terminal (TM) when the name of the selected accessible network is signaled by the terminal.

10 - Terminal implementing the method according to one of any of claims 1 to 9.