MXPA99004106A - Method and apparatus for performing position- and preference-based service selection in a mobile telephone system - Google Patents

Abstract

The mobile telephone system employs a fleet of satellites (14) and a set of gateway ground stations (10) arranged around the globe for handling communications to and from mobile communication units such as mobile telephones. Signals are transmitted between a subscriber (12) unit and the nearest gateway (10) via one or more of the satellites (14). The gateway is connected to a set of individuel service providers (16) such as local telephone system. The individual service providers may be constrained for various reasons such as contractual or other legal constraints to handle communications only from subscriber units (12) located in certain geographical areas such as within only certain countries or portions of countries. For a mobile communication from a particular subscriber unit (12), the gateway selects (10) a service provider (16) capable of handling the communication. In one implementation, the selection is based upon the location of the subscriber unit and upon any preferences specified by the subscriber unit. In other implementations, the selection is based on other parameters such as the altitude, speed or velocity of the subscriber unit or the time of day or date upon which the communication is initiated.

Description

METHOD AND APPARATUS FOR MAKING, IN A MOBILE TELEPHONE SYSTEM, THE SELECTION OF SERVICE BASED ON THE POSITION AND PREFERENCE BACKGROUND OF THE INVENTION Field of the Invention The invention relates in general to mobile telephony systems and, in particular, to the selection of the service provider in a mobile telephone system.

Description of the Related Art Satellite-based mobile telecommunications systems are being developed that allow a subscriber unit for mobile communications, such as a mobile phone, to be used almost anywhere in the world. In one system, illustrated in Figure 1, a fleet of low Earth orbit satellites is used together with a set of terrestrial base stations 10 called "gateways". The signals are transmitted from a subscriber unit 12 to the satellites 14 (shown as a single satellite for ease of drawing) then retransmitted down to the gateway 10 for routing them to one from a set of local service providers, denoted in general as 16, which provide the interconnection with the networks P1296 / 99MX local landline telephones or other communications networks operated by a service provider. Depending on the nature of the communication, the signals are finally routed to, for example, an i telephone connected to the landline network or to a mobile telephone operating perhaps in another part of the world covered by a different gateway or perhaps a system of computers. The signals can encode voice communications such as telephone conversations or data communications such as, for example, facsimile transmissions, Internet connection signals, etc. The subscriber unit 12 can be a portable mobile phone, a mobile phone mounted on a boat, train or airplane, a desktop laptop computer, a personal data assistant or any other suitable communications unit, provided with the appropriate equipment to communicate with the catwalk by the satellite fleet. A single gateway can handle all communications traffic within an area that covers an area as large as 2,000 by 3,000 kilometers. Figure 2 illustrates an exemplary coverage area 18 of a gateway 20 operating in Europe. As can be seen, the coverage area covers many countries. Each country usually has one or more service providers. Depending on the implementation, each service provider can operate P1296 / 99MX only within a country or perhaps only within a portion of a country. These restrictions may result from physical limitations on the capacity of the service provider system or contractual restrictions or other legal restrictions. For example, even when operationally capable of doing so, a service provider in France may not be legally and / or legally able to handle the mobile communications of a subscriber unit operating in Italy and vice versa. Hence, for the subscriber units in France (such as the 22nd unit), the gateway that routes the communications through a French service provider, such as TE.SA.M .; whereas, for subscriber units in Italy, a gateway may be needed to route communications through an Italian service provider, such as Finmeccanica. In addition, as represented by arrow 24, the subscriber units can move from one country to another. Even within a single country, the gateway may be needed to selectively route communications to different service providers, depending on the location of the subscriber unit within the country. In addition, the operator of the subscriber unit may be contractually obligated to use certain service providers in certain locations or may P1296 / 99MX be subject to other legal restrictions. In addition to any contractual limitations that may prevent the telephone connections of the subscriber unit from being connected to particular service providers, the user of the subscriber unit may simply have certain preferences with respect to which service provider to use. For these and other reasons, it may be desirable for the gateway to have the ability to reliably coordinate access among numerous service providers and among numerous mobile telephony users in a large geographic area. Until now, an adequate system for that purpose has not been developed, particularly one that considers the user's preferences. The aspects of the present invention are directed towards the supply of said system.

SUMMARY OF THE INVENTION In accordance with one aspect of the invention, a system is provided for selecting a service provider, based on the location of a subscriber unit or perhaps based on the service provider's preferences provided by the subscriber unit or, based on both. The service provider can alternatively be selected based on altitude, speed or P1296 / 99MX speed of the subscriber unit or in the time of day or date or in a combination thereof. The system that can be part of a ground base station, gateway, is used in connection with a mobile communication system or other wireless communication system, such as a satellite based communication system, which has two or more service providers. The system selects one of the service providers for use in receiving signals from a subscriber unit and for routing signals to the subscriber unit, such as a mobile telephone. To this end, the system can interconnect a local Public Switched Telephone Network (PSTN) with the subscriber unit through the selected service provider. The selection of the service provider is effected, for example, as part of installation operations of a telephone connection initiated by the subscriber unit or terminated in the subscriber unit or, as part of an access procedure by registration in the system, initiated by the subscriber unit. In an implementation where the selection is based on the location, different service providers can handle the communications of the subscriber units in different geographical areas. In accordance with the foregoing, the P1296 / 99MX to select one of the service providers can operate to identify the geographic area in which the subscriber unit is located and selects an available service provider to handle communications from the subscriber units in that geographic area. The geographic areas of the service providers can overlap. Hence, in some particular area, two or more service providers may be available. The different geographical areas can be different countries or different parts of the same country. The availability of a service provider to handle mobile communications from the geographic area of the subscriber unit may be restricted, in part, by operational factors or contractual factors or by other legal factors. The location of the subscriber unit can be determined in accordance with any of the variety of techniques. For satellite based systems, the location can be determined based on time differences and frequency shifts of the signals received by the satellites and coming from the subscriber unit. Alternatively, the subscriber unit may be provided with some means to determine its own location, such as a unit of the Global Positioning System (GPS). In one implementation, P1296 / 99MX the location of the subscriber unit can be approximated with a degree of confidence and the service provider is selected based on, partially, in the degree of confidence, The location of the subscriber unit, once determined, is applied to a table or another medium, which lists all the service providers available to handle the mobile communications of that area of location. The table considers the aforementioned restrictions, such as contractual restrictions or other legal restrictions. Based on the location of the subscriber unit, the table can identify that a service provider is available, that no service provider is available, or that more than one service provider is available to handle communications from the unit subscriber If it is available to more than one service provider, the system operates to select one of the service providers, based on the preferences provided by the subscribing unit.

The preferences can be provided as part of a message to access the system of the subscriber unit (used at the origin of a subscriber unit, in response to an incoming call, an access registration system, etc.), or may be in response to a survey by the system. The preference P1296 / 99 X specified by the subscriber unit may be the identification of the last service provider to which the subscriber unit was registered. In the case where the system finds the preferences of the subscribing unit, the system sets a timer when issuing the request and if the timer ends its time interval before receiving a response, the system terminates the additional action with respect to that communication. In particular, for example, the system terminates the installation of the connection. If only one service provider is available, the system only selects that service provider. If none is available, the system notifies the subscriber unit that there are no service providers available and that, therefore, mobile communication can not proceed.

BRIEF DESCRIPTION OF THE DRAWINGS The particularities, objects and advantages of the present invention will be more evident from the following detailed description set forth below, when considered together with the drawings, in which similar reference characters are correspondingly identified throughout. the text and, where: Figure 1 is a diagram representing a satellite-based mobile telecommunications system P1296 / 99MX that employs a footbridge land station; Figure 2 is a diagram representing an area of coverage and emplificativa of a single ground station of the gangway of the system of Figure 1; Figures 3A and 3B together provide a flow diagram illustrating a method, implemented in accordance with an exemplary implementation of the invention, to select a provider of . service for the base telephone system t 10 satellite that employs a footbridge ground station; Figure 4 is a diagram representing the satellite-based mobile telephony system that performs the method of Figures 3A and B and that within the gateway ground station of the system has a means to determine the location of a subscriber unit; and Figure 5 is a diagram representing a satellite-based mobile telephone system similar to that of Figure 4 but that, where the subscriber unit includes the means to determine the location.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES With reference to the rest of the figures, the preferred and exemplary embodiments of the invention will be described below. The modalities P1296 / 99MX will initially be described at a high level with reference to the satellite-based mobile communications system, illustrated in Figures 3-5, which uses the location information of the subscriber unit and the user's preferences to select the service provider . Figure 4 shows an implementation where a gateway land station attempts to determine the location of the base subscriber unit. Figure 5 shows an implementation where the subscriber unit determines its own location by GPS techniques. The preferred embodiment of the invention conducts the processing of the connection, in accordance with the IS-41 standard, whose use is well known in the art. The flow chart of Figures 3A and 3B illustrates the operations performed during the initiation of a connection from a subscriber unit. The figure illustrates, in series, the two operations carried out by the subscriber unit and those carried out by the gateway ground station. The transmissions between the subscriber unit and the ground station are represented by dashed arrows. All these transmissions are achieved by transmitting signals to one or more satellites, which relay the signals back to the earth. Initially, in step 100, the earth station transmits system parameters over a P1296 / 99MX radiolocation channel, which identifies the gateway (via gateway_id), the service providers connected by the gateway (through service_id) and any other appropriate system parameters, such as satellite beam_id. The parameters of the system are transmitted repeatedly and periodically, so that any subscriber unit in the area of coverage of the ground station can receive the information. The list of broadcast service providers specifies each service provider connected to the gateway, including service providers that may not be available for use by the subscriber unit in its current position, due, for example, to operational limitations or contractual. In step 102, the subscriber unit receives the system parameters on the radiolocation channel. This step is usually carried out when the subscriber unit is turned on or energized. The user then attempts to initiate a telephone call or other telephone connection in step 104, at which time the subscriber unit transmits the access information on an access channel including the access registration requests, the origin information and the requests for access. channel. The subscriber unit also transmits a selected service_provider_ID, if available, and P1296 / 99MX one registration bit. In this regard, the subscriber unit first has access to a table of preferred service providers or to another database (not shown) within the subscriber unit, which identifies the preferred service provider. Depending on the implementation, the subscriber unit may store only a single preferred service provider, different preferred service providers for each gateway coverage area or perhaps different preferred service providers for different times of the day or for different dates, etc. If no preferred service provider is listed, the mobile phone transmits the ID of the last service provider with which the mobile telephone was registered, perhaps as a result of a previous telephone connection or simply does not transmit any service provider ID. If the subscriber unit transmits the ID of the last registered service provider, the subscriber unit also transmits a register bit of 1; otherwise, the registration bit is transmitted as 0. 'If no preferred service provider is available or there is no last registered service provider, the mobile phone does not transmit any information with respect to the service provider. In other implementations, the subscriber unit can transmit multiple service provider ID's, P1296 / 99MX ordered in accordance with the preferences or can transmit service_provider_ID 's with which, for some reason, the subscriber unit can not connect or with which it will not be allowed to connect. In step 106, the gateway receives the messages from the access channel and attempts to determine the location of the subscriber unit in order to determine which service providers are available to handle the connections of the subscriber unit. In one embodiment, the subscriber units transmit to the gateway the information representative of the relative time delays and frequency shifts of the signals received in the subscriber unit from one or more satellites. Using this information and, the information that identifies the location of the satellites, the gateway approximates or estimates the location of the subscriber unit. Various methods for positioning the position in satellite-based wireless communication systems are described in the United States patent applications, entitled "Unambiguous Posi tion Determination Using Two Low-Earth Orb t Satellites", which has the application number (which will be assigned to you, Attorney Reference Number PA278), "Posi tion Determination Using One Low-Earth Orbi t Satelli", which has the application number (which will be assigned to you, P1296 / 99MX Lawyer Reference PA286), "Passive Position Determination Using Two Low-Earth Orbi t Satelli tes", which has the application number (which will be assigned to you, Attorney Reference Number PA287), "Ambigui ty Resolution For Ambiguous Positioning Solutions Using Satelli Beams ", which has the application number (which will be assigned to you, Attorney Reference Number PD456)," Determination Of Frequency Offsets In Communication Systems "which has the application number (which will be assigned, Lawyer Reference Number PA300) and "Time And Frequency Precorrection For Non-Geos tationary Satelli Systems", which has the application number (which will be assigned to you, Attorney Reference Number PA338), which are incorporated in the present as a reference. The gateway also assigns a factor or confidence level that identifies how reliable or accurate the location determination is. The confidence level can be low when the location is determined using the techniques described above that use relative time and frequency calculations. However, the confidence level is usually at least sufficient to reliably identify the subscriber unit that is in a particular country or within a region of a particular service provider within a country. In the modality that will be analyzed below, where GPS techniques are used, the determination of the P1296 / 99MX location can be very accurate and therefore, the confidence factor can be very high. In step 108, the gateway determines which service providers are available to handle the telephone connection initiated by the subscriber unit based on the location of the subscriber unit. In this regard, the gateway has access to the location table of the service provider that represents the range of locations that each service provider managed by the gateway can cover. The range of locations can be represented, for example, as a range of latitudes and longitudes. As indicated, the range of locations may be affected by contractual restrictions or other legal restrictions or by physical operation restrictions. In any case, the gateway compares the location of the subscriber unit with the coverage information of the service provider of the database and identifies those service providers that are available. The determination of the availability of a service provider can be affected by the confidence factor of the determination of the location. For example, if it is found that the location of the subscriber unit is close to a limit or another dividing line between two coverage areas of service providers but, the confidence level is low, as such P1296 / 99MX means that the system can not be sure of which area of coverage the subscriber unit is in. It may be necessary, perhaps on contract lands, to declare that no service provider is available and therefore can not be completed. the telephone connection. In other implementations, any service provider that has a coverage area in which the subscribing unit may be, is identified as available. Thus, if it is determined that the subscriber unit is in Germany but the trust level is so low that instead of this, the subscriber unit can actually be in France, the gateway designates as available all the appropriate service providers in France. France or in Germany. Other variations and implementations are also possible. In this way, the gateway identifies a list of available service providers, if any. If the subscriber unit transmits an ID of the preferred service provider, the gateway determines whether the preferred service provider is among the available service providers and eliminates the others. If the subscriber unit transmits a list of service providers that are unacceptable, the gateway removes them from the list of service providers available to that subscriber unit. If the subscriber unit transmits a list of P1296 / 99MX acceptable service providers ordered based on preference, the gateway picks up or takes the most preferred. If the subscribing unit does not transmit a preferred service provider but instead transmits to the last registered service provider as identified by the registered registration bit and that provider is on the list, the gateway removes the rest of the tickets. Finally, this process produces a list of available service providers that has no entries, has an entry or has multiple entries. Next, the gateway determines, in step 110, whether it needs to negotiate with the subscriber unit to allow the selection of a single service provider. If there are no service providers or only the list remains a single service provider of the service providers available, then negotiation is not necessary. If none is left, a signal is sent to the subscriber unit indicating that this connection installation can not proceed. If more than one service provider remains in the list, then the gateway negotiates with the subscriber unit to get the subscriber unit to select one of the available service providers. If it is determined that no negotiation is required, in step 110, then the execution passes P1296 / 99MX to step 112, wherein the gateway assigns a traffic channel to the mobile telephone and transmits the allocation information of the traffic channel on the radiolocation channel to the subscriber unit. In the preferred embodiment, the traffic channel is a non-shared private signaling channel and user traffic bearer channel. The information of the traffic channel assignment includes the identification of the only service provider identified by the gateway. The subscriber unit receives the allocation information from the traffic channel identifying the service provider, in step 114, and proceeds with the installation of the connection in step 116. In some implementations, the subscriber unit may store a list of providers of unacceptable service and, if the service provider identified in the traffic channel assignment message is unacceptable, the subscriber unit aborts the telephone connection or notifies the gateway that the service provider is unacceptable. If it is determined that negotiation is required, in step 110, then the execution proceeds to step 118, wherein the gateway assigns a traffic channel to the mobile telephone and transmits the information of the traffic channel assignment over the channel of radiolocation to the subscriber unit without ID of the service provider. The P1296 / 99MX subscriber unit receives the information transmitted in step 120. After which, the gateway transmits on the traffic channel, in step 122, the list of acceptable service providers. The mobile station receives the list of service providers available in step 124. Referring now to Figure 3B, after transmission, the fixed gateway or places a timer, step 126. The subscriber unit selects from the service providers the most preferred, in step 128, when compared against a pre-stored list and transmits the corresponding service provider ID, in step 130, which receives the gateway in step 132 over the allocated traffic channel. If the timer set in step 126 concludes its period of time before the gateway receives the most preferred service provider, in step 132, the gateway terminates the connection installation in step 134 and, therefore, does not step 132 is performed. It should be noted that in the preferred embodiment of the invention, only steps 118-134 are required if the subscriber unit does not initially transmit the information of the preferred service provider in step 104, such as if during the steps 104 - 110 a suitable service provider could not be determined. Hence, the subscriber unit and the catwalk perform the steps together to select a P1296 / 99MX is an appropriate service provider, based on the location of the subscriber unit and any preferences specified by the subscriber unit Once the selection is established, the subscriber unit and the gateway proceed with the processing of the connection In one embodiment of the invention, the location of the subscriber unit is periodically updated during the connection and, if it is found that the subscriber unit has crossed over an area where the original service provider is no longer available, the gateway and the subscriber unit renegotiates a new service provider and the appropriate steps of Figure 3 are repeated. Preferably, these steps are performed without disturbing the mobile communication in progress, however, in some situations, it may be necessary to terminate the connection if a new service provider can not be found, Figure 4 illustrates the relevant components of a satellite base system, configured to perform the steps of Figures 3A and 3B. The system is similar to that of Figure 1, where similar components are identified by like reference numbers with an increase of 100 and only the relevant differences will be described in detail. A gateway land station 210, a subscriber unit 212 and a satellite are shown P1 96 / 99MX 214. 'The signals are transmitted between the subscriber unit and the gateway via the satellite. The gateway is also interconnected with a set of service providers, generally denoted as 216, which provide interconnection with local landline telephone networks or with other communication networks. The subscriber unit 212 includes a list 218 of preferred service providers for use in the selection of a preferred service provider. As indicated above, the preferred service provider ID is transmitted to the gateway 210 either as part of an access request on the access channel or in response to the gateway query on that received on the radiolocation channel. Depending on the implementations, the list of preferred service providers can identify only a single service provider, a single service provider per gateway or perhaps a single service provider per country or area. The list can also identify service providers in order of preference. The list can also identify service providers that the user of the subscribing unit would prefer not to use, including those who, for one reason or another, the user will not have access to or may not have access to. Also depending on the P1296 / 99MX implementation, the list of preferred service providers the program the manufacturer of the subscriber unit, the staff at the point of sale, or the user. If this is the case, the subscriber unit is provided with circuitry or software to receive the information of the preferred service provider from the user, perhaps an entry by means of the numeric keypad of the subscriber unit or perhaps selected from a list presented to the user of the subscriber unit. a set of pre-stored allowable service providers. The database can, alternatively, be updated electronically through a data port or updated based on the signals received through mobile communications coming from a gateway. In each case, all the IDs of the permissible service providers are pre-stored, so that the user does not need to know the ID's. Rather, the user needs to know only the name of the service provider. As can be appreciated, a wide variety of implementations are available in accordance with the principles of the invention. Gateway 210 includes a list 220 of service providers that identifies all service providers connected to the gateway, a service provider location table 222 that identifies the permissible coverage areas of each service provider.

P1296 / 99MX service provider of the list 220, a location determination unit 224 of the subscriber unit and a determination unit 226 of the available service provider. The location determination unit of the subscriber unit identifies the location of the mobile and applies said information to the location table 222 to identify the service providers available to handle the telephone connections of the subscriber units in said location. As noted above, the ability of a service provider to handle connections may be subject to contractual restrictions or other legal restrictions. Also, as indicated, the location of the subscriber unit is determined subject to a certain degree or accuracy or confidence factor. The confidence factor can be used, in the manner discussed above, by the determination unit 226 of the service provider available for the identification of acceptable service providers. After the list of acceptable service providers is generated, the gateway 210 performs the steps described above to negotiate, if necessary, with the subscriber unit 212 to achieve the selection of one of the service providers. Once a service provider has been selected, the gateway routes the signals between the subscriber unit and the P1 96 / 99MX service provider selected for the additional processing of the telephone connection. After the telephone connections initiated by the subscriber unit, the re-identification of a service provider is required, which may or may not be a service provider different from the one previously selected. Figure 5 illustrates the relevant components of a system similar to that of Figure 4 (where similar components are identified by similar reference numbers, increased by 100) but, where the subscriber unit includes a GPS unit to determine the location. Only the relevant differences will be described in detail. It is shown that the subscriber unit 312 includes a GPS unit 324 for determining the present location of the subscriber unit. The GPS unit 324 determines the location of the subscriber unit in accordance with conventional GPS techniques and, in connection, with a fleet of GPS satellites (not shown separately). The location can be determined before starting a telephone connection or can be provided in response to a query from the gateway. In any case, once the location is determined, the subscriber unit transmits to a gateway 310 the coordinates that identify the location, to allow P1296 / 99MX that the gateway determines which service providers are available for that location. The gateway then proceeds in the manner described above with reference to Figure 3 to negotiate, if necessary, that the subscriber unit selects one of the service providers. In this way, the techniques of the invention have been described with reference to a telephone connection initiated by a subscriber unit. Similar techniques are executed for connections terminated by the subscriber unit. Also, similar techniques are executed to register a subscriber unit with the ignition or energization and to periodically update the register. In addition, similar techniques can be executed for other mobile communications in addition to telephone calls. What has been described is a system for selecting service providers for a mobile telephone system, where the selection is based on the user's location and preferences. As indicated, other selection criteria consistent with the principles of the invention may also be used. For example, a selection may be based, in whole or in part, on the frequency of transmission used, the time of day or date, or other factors. The subscriber unit can store information that specifies the service rates of P1296 / 99MX different service providers and select the preferred service providers based on the lowest current rate. Also, the selection can be based on exclusive factors, rather than on inclusive factors. In this regard, the selection process can select all service providers not specifically excluded in some way, perhaps as a result of billing issues with respect to specific mobile users. Regarding the selection based on the location or based on the position, the position need not be limited only to the latitude / longitude positions on the ground. The selection can be based additionally on altitude and speed. For example, different discrimination factors may be used to select preferred service providers for subscriber units in airplanes, ships or trains than for portable subscriber units carried by pedestrians or in a car. As the speed, because the speed includes an address vector, the service provider having the capacity to provide the longest service can be selected given the speed and address of the subscriber unit. For example, if the subscriber unit is on an aircraft, initially over a geographic area where two service providers are available but that are P1296 / 99MX moves to an address where only one of the two providers will be available soon, the system will select that service provider as the best service provider for that particular mobile communication. In general, the principles of the invention can be applied to make the selection of the service provider based on any suitable factor. In addition, the principles can be applied to the selection of other operational characteristics in addition to the service providers. Also, the principles of the invention are not limited to satellite-based mobile communication systems but are also applicable to other communication systems. Exemplary embodiments have been described primarily with reference to block diagrams illustrating elements of the apparatus and flowcharts that illustrate mainly the steps of the method. With respect to the flow diagrams, each block thereof represents both a step of the method and an element of the apparatus for executing the declared step. Depending on the implementation, each element of the apparatus or portions thereof may be configured in hardware, software, firmware or combinations thereof. It should be noted that not all the necessary components for the P1296 / 99MX completes implementation of a practical system. Rather, only those components necessary for a perfect understanding of the invention have been illustrated and described. Finally, the foregoing description of the preferred and exemplary embodiments is provided to enable any person skilled in the art to prepare or use the present invention. The various modifications to these modalities will be readily apparent to those skilled in the art and the generic principles defined herein may be applied to other modalities without using the inventive faculty. Thus, it is not intended that the present invention be limited to the embodiments shown herein but that it be in accordance with the broader scope consistent with the novel principles and particularities disclosed herein.

P1 96 / 99MX

Claims (49)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property: 1. In a mobile communications system that has two or more service providers, a system for selecting a service provider to be used in connection with the subscriber unit, the system comprises: a means for determining the location of the subscriber unit; and a means to select one of the service providers based on the location of the subscribing unit. The system according to claim 1, wherein the different service providers handle the communications of the subscriber units in different geographical areas and, where, the means to select one of the service providers operates to identify the geographical area where the subscriber unit is located and selects a service provider that handles communications in that geographic area. 3. The system according to claim 2, wherein the different geographical areas are different countries. P1296 / 99MX 4. The system according to claim 2, wherein the different geographical areas are within a single country. The system according to claim 1, wherein the means for determining the location of the subscriber unit approximates the location with a certain degree of confidence; and wherein the means to select one of the service providers selects a service provider based, partially, on the degree of trust. The system according to claim 1, wherein the system includes at least one satellite to emit the signals transmitted by the subscriber unit and wherein the means for identifying the location of the subscriber unit includes a means for determining the location of the unit subscriber based on the signals received from the satellite. The system according to claim 6, wherein the signals received from the satellite specify the time delays and frequency shifts of the signals sent from the subscriber unit to the satellite and the means to identify the location approaches the location based on time delays and frequency shifts. The system according to claim 1, wherein the means for determining the location of the P1296 / 99MX subscriber unit operates to receive a signal from the subscriber unit that identifies the location of the subscriber unit. The system according to claim 8, wherein the signal identifying the location of the subscriber unit represents the location in coordinates of the global positioning system. The system according to claim 1, wherein the means for selecting a service provider based on the location of the subscriber unit further includes a means to select from among the multiple possible service providers that handle the geographical area of the subscriber unit based on the preferences provided by the subscribing unit. The system according to claim 10, wherein the preferences are provided by the subscriber unit in an access channel message transmitted by the subscriber unit. The system according to claim 1, wherein the system further includes: means for determining if more than one service provider is available to handle communications of the geographic area of the subscriber unit; a means that responds to the determination that more than one service provider is available P1296 / 99MX possible, to transmit a signal to the subscriber unit requesting the identification of a preferred provider of the available service providers; and means for receiving the response signal from the subscriber unit identifying a preferred service provider. The system according to claim 12, further including: means for setting a timer with the transmission of a signal to the subscriber unit requesting the identification of a preferred provider from the available service providers; and a means operating in response to the time elapsed in the timer before a response signal is received from the subscriber unit, to select a provider from the available service providers. The system according to claim 12, wherein the preferences are provided by the subscriber unit in a traffic channel message in response to a request message for selecting the radiolocation channel transmitted to the subscriber unit. 15. The system according to claim 1, further including: means for receiving the identification of the P1296 / 99MX last service provider with which the mobile phone was registered; means for determining if more than one service provider is available to handle the communication of the geographical area of the subscribing unit; and wherein the means for selecting the service provider selects the last service provider identified by the mobile telephone, if this is one of the service providers available for the geographical area of the subscriber unit. 16. In a mobile communication system having two or more service providers, a system for selecting a service provider to be used in connection with a subscriber unit, the system comprises: a means for determining a parameter associated with the subscriber unit , the parameter will be selected from a group consisting of the location, altitude, speed or speed of the subscriber unit and the time of day or date; and a means to select one of the service providers based on the parameter. 17. In a mobile communication system having two or more service providers, a method for selecting a service provider to use in connection with a subscribing unit, the method P1296 / 99MX comprises the steps of: determining the location of the subscriber unit; and selecting one of the service providers based on the location of the subscribing unit. The method according to claim 17, wherein different service providers handle the communications of the subscriber units in different geographic areas and, where the step of selecting one of the service providers is executed to identify the geographic area in which is placed the subscriber unit and to select the service provider that handles communications in that geographical area. 19. The method according to claim 18, wherein the different geographical areas are different countries. The method according to claim 18, wherein the different geographical areas are within a single country. The method according to claim 17, wherein the step of determining the location of the subscriber unit approximates the location with a certain degree of confidence and, where the step of selecting one of the service providers selects a provider of service also based, in part, on the P1296 / 99MX degree of confidence. The method according to claim 17, wherein the system includes at least one satellite to emit the signals transmitted by the subscriber unit and, wherein the step of identifying the location of the subscriber unit includes the step of determining the location of the Subscriber unit based on the signals received from the satellite. The system according to claim 22, wherein the signals received from the satellite specify the time delays and frequency shifts of the signals sent from the subscriber unit to the satellite and the step of identifying the location approximates the location based on in time delays and frequency shifts. The method according to claim 17, wherein the step of determining the location of the subscriber unit operates to receive a signal from the subscriber unit that identifies the location of the subscriber unit. 25. The method according to claim 24, wherein the signal identifying the location of the subscriber unit represents the location in coordinates of the global positioning system. 26. The system according to claim 17, wherein the step of selecting a service provider P1296 / 99MX based on the location of the subscriber unit further includes the step of selecting among multiple possible service providers that handle the geographical area of the subscriber unit based on the preferences provided by the subscriber unit. The method according to claim 17, wherein the preferences are provided by the subscriber unit in an access message transmitted by the subscriber unit. The method according to claim 17, wherein the method further includes the steps of: determining whether more than one service provider is available to handle communications of the geographic area of the subscriber unit; if more than one possible service provider is available, transmit a signal to the subscriber unit requesting the identification of a preferred provider from the available service providers; and receiving a response signal from the subscriber unit that identifies a preferred service provider. The method according to claim 11, further including the steps of: setting a timer with the transmission of a signal to the subscriber unit requesting the identification of a preferred provider of the P1296 / 99MX service providers available; and if the timer time elapses before a response signal is received from the subscriber unit, select one of the available service providers. The system according to claim 28, wherein the preferences are provided by the subscriber unit in a traffic channel message in response to a request message for selecting the radiolocation channel transmitted to the subscriber unit. The method according to claim 17, further including the steps of: receiving an identification of the last service provider used by the mobile telephone; determine if more than one service provider is available to handle communications from the geographic area of the subscribing unit; and wherein the step of selecting a service provider is executed to select the last service provider identified by the mobile telephone if this is one of the service providers available for the geographical area of the subscribing unit. 32. In a mobile communication system that has two or more service providers, a method to select a service provider to use it P1296 / 99MX in connection with a subscriber unit, the method comprises the steps of: determining a parameter associated with the subscriber unit, the parameter will be selected from a group consisting of the location, altitude, speed or speed of the subscriber unit and the time of day or date; and select one of the service providers based on the parameter. 33. In a mobile communication system that has two or more service providers and one or more ground stations, a method executed by a subscriber unit to select one of the service providers, comprising the steps: storing a list of providers service arranged by preference; receive a signal that identifies the service providers operated by the nearest ground station in the system; examine the list to identify the most preferred service provider of service providers operated by the nearest ground station in the system; and transmitting a signal identifying the most preferred service provider. 34. The method according to claim 33, wherein the steps are executed to initiate a connection P1296 / 99MX telephone from the subscriber unit. 35. The method according to claim 33, wherein the steps are executed in response to receiving a signal indicating a completed telephone connection in the subscriber unit. 36. The method according to claim 33, wherein the steps are executed to register the subscriber unit with the service provider after energizing or turning on the subscriber unit. 37. The method according to claim 33, wherein the steps are executed to update the registration of the subscriber unit with the service provider after a predetermined period of time elapses. 38. The method according to claim 33, wherein different service providers handle communications from the subscriber units located in different geographical areas. 39. The method according to claim 38, wherein the different geographical areas are different countries. 40. The method according to claim 39, wherein the different geographical areas are within a single country. 41. The method according to claim 33, wherein the step of transmitting the signal identifying the most preferred service provider is executed as P1296 / 99MX part of an access request message. 42. The method according to claim 33, wherein the step of transmitting the signal identifying the most preferred service provider is executed in response to a request from a preferred service provider received from the ground station. 43. The method according to claim 33, wherein, if a preferred service provider is not found, the step of transmitting a signal identifying the most preferred service provider is executed instead of transmitting an identification of the last service provider used by the mobile telephone. 44. The method according to claim 43, wherein, if the preferred service provider is not found and the last registered service provider is not found, the step of transmitting a signal identifying the most preferred service provider is executed instead to transmit a signal indicating that the service provider was not found. 45. The method according to claim 33, wherein different service providers handle the communications from the subscriber units located in different geographical areas and, where the step of receiving a signal identifying the service providers includes the initial steps of: receiving a signal from the base station Terrestrial P1296 / 99MX requesting an identification of the location of the subscribing unit; determine the location of the subscriber unit; and transmitting a signal to the ground base station that identifies the location of the subscriber unit. 46. The method according to claim 45, wherein the step of determining the location of the subscriber unit is executed using a global positioning system. 47. The method according to claim 45, wherein the step of determining the location of the subscriber unit approximates the location with a certain degree of confidence. 48. In a mobile communication system having two or more service providers, a system for selecting a service provider to be used in connection with a subscriber unit, the system comprises: a unit for determining the location of the subscriber unit; a storage unit from the list of service providers; a storage unit from the location of the service provider operating to store a representation of an allowable range of locations of P1296 / 99MX the subscriber unit from which each service provider listed in the storage unit of the service provider list can process the communications; and a unit of determination of available service providers that operates to identify if any of the service providers listed in the storage unit of the service provider list is available to process the communications of a subscriber unit based on the location of the service provider. the subscriber unit as determined by the unit of determination of the location of the subscriber unit and of the range of permissible locations listed for each service provider represented in the storage unit of the location of the service providers. 49. The system according to claim 48, wherein the location determining unit of the subscriber unit operates to receive a signal identifying the location of the subscriber unit. P1296 / 99MX SUMMARY OF THE INVENTION A mobile telephone system is presented that uses a fleet of satellites (14) and a set of terrestrial runway stations (10) located around the world, to handle communications to mobile communication units and from them, such as mobile phones. The signals are transmitted between a subscriber unit (12) and the nearest gateway (10), through one or more of the satellites (14). The gateway is connected to a set of individual service providers (16), like the local telephone system. Individual service providers may be restricted for various reasons, such as contractual restrictions or other legal restrictions to handle communications only from subscriber units (12) located in certain geographic areas, or within only certain countries or zones of countries. For mobile communication from a particular subscriber unit (12), the gateway (10) selects a service provider (16) that has the ability to handle the communication. In one implementation, the selection is based on the location of the subscriber unit and in any preferences specified by the subscriber unit. In other implementations, the selection is based on other parameters such as altitude, speed or speed of P1296 / 99MX the subscriber unit or the time of day or the date on which communication begins. P1296 / 99MX