HK1101461B - System and method for providing cellular service to a plurality of individuals - Google Patents

Description

System and method for providing cellular service to multiple individuals

Technical Field

The present invention relates to communication systems, and more particularly to communication systems for providing wireless communication links between one or more occupants and ground stations on a mobile or remote platform, wherein the systems and methods enable equal access to a plurality of ground service providers such that one or more of the service providers can participate in facilitating establishment of a communication link for the occupant.

Background

Providing cellular service to occupants traveling on mobile platforms, such as buses, trains, ships, or airplanes, or individuals located in remote areas not covered by traditional cellular carriers (carriers), has proven to be a challenge. This is because cellular telephone networks, while well known and ubiquitous, still provide service in fixed geographical areas. Cellular telephone users enter the cellular network while physically located in a geographic region allocated as specified throughout the world. The user's personal profile information is then looked up in the operator's database to access the service (local) operator's network. If the network that the user is physically accessing is not the user's own cellular service provider, the network is referred to as an "out" network.

When a subscriber attempts to access his/her cellular service provider through a foreign network, a roaming arrangement between the subscriber's operator, i.e. the Home Location Register (HLR), and the network access provider, i.e. the Visitor Location Register (VLR), is required in order to provide the subscriber with cellular service in the geographical area covered by the foreign network. Roaming arrangements between all operators are not ubiquitous and service is denied to users in areas where these roaming arrangements have not been adopted. Thus, there is a need for a cost-effective, global, equal access method that enables cellular telephones to be used on mobile platforms that often move at high speeds across multiple geographic cellular regions (particularly for modern day jet aircraft), and where no cellular coverage can exist, such as at a distance, or where coverage is no longer available. Conventional cellular roaming arrangements do not provide the ability to connect users in situations where no particular cellular infrastructure is in place to cover the location of the user (e.g., a mobile platform such as an airplane, ship, train, or remote location). Moreover, due to specific geographic licensed operational restrictions, no single cellular operator can justify implementing global service coverage. As a result, mobile users (i.e., users traveling on buses, ships, trains, planes, etc.) are required to end an existing connection before roaming into an area covered by a foreign network, and then to reestablish a connection via a new foreign network.

One attempt to eliminate the problem of enabling mobile users to maintain connectivity with their cellular service providers is to use "pico cells". Picocells (picocells) have been deployed in limited spaces, such as within buildings, even within specific rooms within buildings, so that occupants can communicate with mobile phones and wireless computing devices. For mobile platform (aircraft, ship, etc.) applications, the main technical problems are: mobile or remote picocells cannot be connected to the ground-based cellular infrastructure at a sufficiently low cost and provide equal access to all cellular service providers capable of serving the mobile or remote picocells. Connecting to only a single cellular service provider would not be a viable solution as this would exclude the portion of people who are not subscribed to the services of or having roaming agreements with that particular cellular operator. This is also highly undesirable for the remaining cellular operators that have been excluded. Furthermore, it is not practical to establish roaming relationships with all cellular operators. Therefore, it is highly desirable that: access to all cellular service providers is provided according to what services all cellular service providers may provide to an end user moving on a mobile platform or located remotely.

It would therefore be highly desirable to provide a system and method that allows occupants at a mobile platform or at a remote location an opportunity to establish a wireless communication link with a user's ground-based cellular service provider, and when the user is outside the geographic coverage area of his/her service provider, and by means of an external network. Such an invention would eliminate the need to rely on roaming agreements for establishing voice and data communications between users on mobile platforms or in remote areas and each user's own cellular service provider when the user is outside the geographic coverage area of his/her cellular service provider.

Disclosure of Invention

The present invention is directed to a system and method for providing communications between cellular subscribers and cellular service providers on a mobile platform or in remote areas when the subscribers are outside the geographic coverage area of any cellular service provider, where each subscriber on the mobile platform or in remote areas can establish a communication link with his/her own service provider or with a service provider having a roaming agreement with the subscriber's own service provider.

In a preferred embodiment, the system includes an access segment located on the mobile platform. The access segment communicates with the user's cellular device located on a mobile platform and establishes a wireless communication link between the mobile platform and a terrestrial segment via a space-based repeater. The terrestrial segment includes a terrestrial carrier interface for communicating with at least one terrestrial-based cellular service provider, and more preferably a plurality of such service providers located in geographically dispersed areas. The terrestrial interface communicates with a control subsystem that performs at least one of authentication and registration functions for a user attempting to establish (or having established) a communication link with a cellular service provider accessing the system.

In a preferred form, the access segment comprises a wireless access segment comprising a mobile base transceiver station located on a mobile platform. A base station control application (BSC) is also located on the mobile platform. The radio access segment communicates with a Platform Bearer Terminal (PBT) on the mobile platform that manages control of the communication link established with the mobile platform. The mobile platform communicates with the terrestrial segment via a space-based transponder and includes an off-platform bearer terminal (OBT). The OBT participates in managing communications with the mobile platform. The OBT is in communication with the ground operator interface and also with the control subsystem. In particular, the terrestrial carrier interface is coupled to the control system and one or more cellular service providers via a wide area network. The terrestrial carrier interface operates essentially as an exit point and an entry point for cellular services between the mobile platform and one or more terrestrial cellular service providers accessing the system.

In a preferred form, the control subsystem includes a Visitor Location Register (VLR) in communication with a Mobile Switching Center (MSC) server. These components each communicate with a terrestrial carrier interface via a wide area network. The VLR serves as a temporary storage of subscriber profiles retrieved from a Home Location Register (HLR) located on a particular cellular network. The MSC server controls the registration and authentication process by interpreting and acting on messages relayed to and from a given HLR via the terrestrial carrier interface. In effect, the VLR and MSC servers are used to help process and monitor the information needed to establish and maintain communications with each subscriber on the mobile platform and the cellular service network that accesses the terrestrial carrier interface of the system.

The system and method of the present invention thus enable users on board a mobile platform, or even users at remote locations, to access their cellular service provider or foreign networks that function on behalf of the user's cellular service provider. Importantly, the system and method of the present invention does not distinguish or restrict access to only selected foreign networks. Rather, any cellular service provider is able to access the network and may participate in providing cellular service to each user on the mobile platform, or each user located remotely.

Drawings

The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 is a block diagram of a preferred embodiment of the present invention;

FIG. 2 is a flow chart of steps performed in authenticating information related to a user on a mobile platform;

FIG. 3 is a flow chart of the steps involved in making an outgoing call from a mobile platform; and

fig. 4 is a flow chart of the steps involved in making an incoming call to a mobile platform.

Detailed Description

The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

Referring to FIG. 1, a system 10 for enabling on-board a mobile platform 12 in accordance with a preferred embodiment of the present invention is shownUser and at least one ground segment 14₁、14₂、14_nWherein each terrestrial segment 14 communicates with one or more cellular service providers 16. In particular, the system 10 enables a user traveling on a mobile platform or located in a remote area to establish a cellular communication link with at least one cellular service provider 16 when the user is outside the geographic coverage area of his/her own service provider, or the coverage area of any cellular service provider. An important advantage of the present invention is that cellular service providers are provided equal access to system 10, and system 10 is not limited to use with only one particular cellular service provider.

The system 10 includes a wireless access segment 18 that is located on the mobile platform 12. It will be immediately apparent, however, that while the following description will refer to a user on a mobile platform 12, the present invention 10 may just as easily be constructed so that the access segment 18 is located at a remote ground facility rather than on a mobile platform. In either implementation, the present invention allows users outside of their cellular coverage area to establish cellular communication links with their own operators or foreign cellular service providers.

With further reference to fig. 1, the wireless access segment is in radio frequency communication with a personal communication device 20 of the user. The access segment 18 effectively forms a "picocell" on the mobile platform 12 that is accessible by the personal communication devices of any particular user on the mobile platform 12.

The radio access segment 18 communicates with a Platform Bearer Terminal (PBT) interface 22 and a platform bearer terminal 24, and a space-based repeater 26 relays information between the PBT 24 and one or more off-platform bearer terminals 28, each of the off-platform bearer terminals 28 being associated with one of the terrestrial segments 14. Each OBT 28 communicates with an associated gateway interface 30, which gateway interface 30 interfaces with at least one cellular service provider 16 accessing the system 10. Each gateway 30 further communicates with, for example, a control subsystem 32 via a wide area network 34, a leased line network, or the internet. The control subsystem 32 includes a Visitor Location Register (VLR)36 and a Mobile Switching Center (MSC) server 38 in communication with the VLR 36.

If additional data communications are desired as well as voice communications, a terminal interface 40 will be included as part of the associated terrestrial segment 14 for routing voice signaling and communication traffic data to the gateway interface 30. The components 30 and 40 of a given ground segment 14 may be viewed as forming a single node. Thus, the component 30₁And 40₁Can be seen as forming node A, part 30₂And 40₂Form node B, and so on. It will be understood that any number of different nodes may be formed. Nodes a and B will typically be located in geographically dispersed areas that may be hundreds or thousands of miles apart. However, each communicates with the control subsystem 32 via a wide area network 34. The only limitation on the number of different nodes that may form the terrestrial segment 14 is: the MSC server 38 and VLR 36 are capable of managing the exchange of information between all of the cellular service networks 16 and the control subsystem 32.

With further reference to fig. 1, the operation of the cellular network will not be described in detail, as this is well known to the person skilled in the art. However, each conventional cellular network 16 may be viewed as including its own public mobile switching center 42, Home Location Register (HLR)44, and Public Land Mobile Network (PLMN) 46. The HLR 44 stores information about subscribers to that particular cellular service provider's network.

As noted above, the wireless access segment 18 may also be installed at a remote geographic location rather than on the mobile platform 12 as illustrated. Moreover, while the mobile platform 12 has been illustrated as an airplane, it will be appreciated that the present invention 10 is not limited to implementation solely with an airplane, but may readily be implemented on a bus, train, ship, or any other vehicle or mobile object for which a cellular service connection is desired. Radio access segment 18 includes a mobile base transceiver station 48, a Base Station Control (BSC) server 50. The standard practice on terrestrial cellular networks is to place (host) the BSC server 50 at a network node dedicated to controlling multiple BTSs 48. However, to avoid binding the BTS 48 to a dedicated ground node and to avoid using an off-platform link for control messages, the BSC server 50 may co-exist near the BTS 48. This does not preclude the location of BSC 50 from being in a more central location, possibly in one of the terrestrial segments 14, which may then be configured to control multiple BTSs 48, as long as the control information exchanged between BSC server 50 and BTSs 48 has been adapted to function properly across the off-platform communication link between mobile platform 12 and terrestrial segment 14.

The BTS 48 manages the transmission and reception of Radio Frequency (RF) signals from the personal communication devices 20 of each user on the mobile platform 12. The transmit power of the BTS 48 is automatically selected and controlled so that it provides the minimum power level required to access the desired area (either on the mobile platform 12 or at the remote location where the access segment 18 is located). Because its coverage is comparable to the physical size of the platform or remote site (i.e., small compared to terrestrial cells), the BTS 48 essentially defines a microcell, picocell, or femtocells. The physical and logical characteristics of the radio frequency link provided by the BTS 48 conform to standards applicable to terrestrial operators, thereby making it compatible with those of the user's personal communication equipment. The BTS 48 is used to transcode information streams including signaling/control and traffic (voice and data) transported over an internet protocol interface 52 between the BTS 48 and the PBT 24.

The BSC application 50 manages the frequency hopping and control of the radio frequency power levels of the BTSs 48. It will be noted that no switching capability is required between these two components. The functions performed by the BSC application 50 may be implemented in dedicated hardware, as is the case in terrestrial cellular infrastructure, or via a software-only implementation that will co-exist with other (unrelated) applications on servers on the platform, as long as that particular server supports a BTS-compatible interface.

With further reference to fig. 1, the PBT interface 22 is only required if other services are provided on the mobile platform 12 in addition to cellular voice and data. PBT interface 22 is responsible for ensuring priority queuing required to minimize voice traffic latency. The PBT 24 communicates with the PBT interface 22 and, in addition to off-platform bearer control, manages transcoding, link acquisition of signals between the access segment 18 and off-platform physical and logical formats.

In addition to error control, each OBT 28 also participates in off-platform link control by facilitating transcoding, link acquisition of signals between off-platform physical and logical formats and those of its associated terrestrial segment 14. Each terrestrial segment 14 is also provided in the radio access segment 18 and the terrestrial cellular network 16₁-16_nSignaling and traffic transport and interfaces between.

Each gateway interface 30 performs the following main functions:

an OBT 28 interface associated therewith to communicate signaling (authentication and call control) and traffic information supporting cellular voice and data services;

with one or more terrestrial cellular network interfaces to deliver authentication, call control, and other SS7 messages (e.g., SMS/EMS/MMS) (short/enhanced/multimedia messaging service);

processing signals and traffic information by: separate signaling packets, convert the packets to SS7 format (if needed), route SS7 packets to an associated switch or SMSC (short message service center) to provide SMS/EMS/MMS services;

interpreting and acting on call control messages whose addressed address is itself;

separate traffic packets, transcode the packets into PCM format (if needed), multiplex the PCM samples onto the link, resulting in associated conversion of the terrestrial cellular network 16 (making traffic to/from the terrestrial wireless network in native (native) format);

the registration and authentication process is engaged by relaying SS7/MAP messages between the HLR 44 of a given cellular provider 16 and the MSC server 38.

The VLR 36 of the control subsystem 32 essentially operates as a database of temporary information about active subscribers operating under the control of the MSC server 38. The data stored in the VLR 36 is, to a large extent, a copy of the corresponding subscriber data obtained from the HLR 44 of the subscriber's cellular service provider 16. The VLR 36 database is preferably truncated to accept only the necessary subscriber information to enable service with respect to the new foreign cellular provider 16 to which the subscriber is visiting, and the database records are purged at the request of the subscriber's home network HLR 44 so that no long-term records are stored in the VLR 36 database. The VLR 36 database also stores mobile platform related data such as an identifier of the platform BTS 48 and an identifier of the particular gateway 30 serving the mobile platform. The VLR 36 also stores information reported in real time from the mobile platform 12, such as latitude, longitude, and if more than one space-based transponder is used in the system 10, the VLR 36 also stores information of which satellite gateway is in contact with the mobile platform 12. As will be appreciated by those skilled in the art of cellular communications, the HLR 44, located within the cellular network of a subscriber's (i.e., user) cellular service provider 16, stores information about the current location of its subscribers being visited in the wireless service area of a foreign MSC, such as MSC 38, and indicates whether the subscriber can receive calls through a different provider network.

In fig. 1, it will be appreciated that the space-based transponder provides a two-way wireless communication link between one or more terrestrial segments 14. Of course, multiple satellite-based transponders may be implemented and only a single space-based transponder 26 is used, merely to simplify the following example illustration of the operation of the overall system 10.

Each ground segment 14₁、14₂Etc. OBT 28₁、28₂Etc. with the space-based transponder 26. Each gateway 30₁、30₂Etc. typically communicate with one or more cellular service providers 16. For example, cellular service provider 16₁Via a suitable communication scheme, such as the SS7 communication messaging protocol, or possibly even via a communication protocol such as the internetSuch as a wide area network, and a gateway 30₁And (4) communication. One or more additional providers 16_1aMay communicate with provider 16₁Contacting, or directly connecting to, the gateway 30₁. For convenience, provider 16_1aIs indicated as being linked to provider 16 via a roaming agreement₁And thus via provider 16₁Indirectly with the gateway 30₁And (4) communication. Thus, it will be appreciated that the connection can be directly to the wide area network 34 (anywhere on earth), or directly to the gateway 30₁、30₂Etc. any cellular provider having a roaming agreement will be able to communicate with its cellular subscribers traveling on the mobile platform 12. As a further example, provider 16_1BThere may be roaming agreements with 10 other cellular providers (not shown in the figure of figure 1). However, each of those 10 other cellular providers will be via at provider 16_1AAnd 16_1BAccess gateway 30 of the link between₁. If one of those 10 providers, such as provider "X", itself has a roaming agreement with 6 other cellular providers, those 6 other cellular providers will be via the network at provider X, provider 16_1BAnd 16_1AAccess gateway 30 of the link between₁. Thus, the system 10 can be exponentially linked to a large number of providers. This feature provides a very flexible arrangement for accommodating virtually any number of independent cellular service providers, and provides each with means for interfacing with its user (either directly or via a roaming arrangement with a different provider). The only major limitation is that the mobile platform 12 communicates with at least one gateway 30. Currently, the gateway 30 is established in the following places: ibaraki, japan; littleton from colorado; leuk, Switzerland; moscow, Russia. However, it will be appreciated that the system 10 may be implemented using more or fewer multiple gateways and further geographically diverse locations.

Referring now to fig. 2, the steps performed by the system 10 of the present invention in authenticating a wireless communication link will be described. Initially, as shown in step 60, the user puts their personal communication device 20 onAnd (4) electricity. The communication device 20 issues an authentication request message. The mobile BTS 49 relays this authentication request to the MSC server 38 as shown in step 62. The MSC server 38 uses the information contained in the authentication request to query the VLR 36 to determine if the personal communication device 20 is currently registered with the VLR 36, as shown in step 64. If the device 20 is not registered, the MSC server 38 identifies the home network (i.e., home provider) associated with the device 20 from the IMSI (international mobile subscriber identity) in the authentication request message and queries the HLR of the home network (e.g., network 16)₂HLR 44) as shown in step 66. SS7/MAP protocol messages are used for this purpose. Alternatively, SS7 messages over IP protocols may be used. The SS7 message is preferred because this method is popular with terrestrial cellular networks.

With further reference to fig. 2, the MSC server 38 then derives from the subscriber's home provider network 16₂The HLR 44 of (a) receives the authentication response as shown in step 68. The MSC server 38 then relays the authentication response to the BSC control application 50, as shown in step 70. The MSC server 38 also generates an entry into the VLR database as shown in step 72. The BSC control application 50 then grants or denies access to the on-platform 18 network, as shown in step 74.

Referring now to fig. 3, the steps involved in performing an outgoing call (i.e., a call initiated by the user of the personal communication device 20) will be described. Initially, the personal communication device 20 sends a call request to the mobile BTS 48, as shown in step 76. The BSC control application 50 verifies the authentication status of the device 20 and responds with a "call in progress" message that is sent back to the device 20, as shown in step 78. The BSC control application 50 then relays the call setup request to at least one gateway interface 30, as shown in step 80. The gateway interface 30 relays this request to the public MSC42 as shown in step 82. The public MSC42 establishes a connection to the called number as shown in step 84. The public MSC42 relays the ALERTING message to the user's device 20 via the gateway interface 30 as shown in step 86. When the called number goes off-hook, the public MSC42 relays a "CONNECT" message to the personal device 20 via the gateway interface 30, as shown in step 88. The personal communication device 20 then acknowledges the call setup completion by sending an acknowledgement message to the public MSC42 as shown in step 90.

Referring now to fig. 4, a typical inbound call setup from the ground segment 14 to the personal communication device 20 will be described. Initially, the number of the user's personal communication device 20 is dialed using an external (i.e., land-based or located on a different mobile platform) device and the user's home MSC42 is contacted, as shown in step 92. The subscriber's home MSC42 looks up the mobile number in the HLR 44 of the home network and determines that the device 20 is now roaming on the terrestrial segment 14 of the system 10, as shown in step 94. The public MSC42 of the subscriber's home network then forwards the "call setup" request to the MSC server 38, as shown in step 96. The MSC server 38 then looks up the called number in the VLR 36 and determines the appropriate serving gateway interface (30)₁、30₂Etc.) identification and mobile BTS identification as shown in step 98. The IP address of the interface 30 and the IP address of the BTS 48 will be used. The MSC server 38 then forwards the "call setup" request to the BTS 48 on the mobile platform 12 via the appropriate gateway interface 30, as shown in step 100. The mobile BTS 48 then sends a "page" request to the personal communication device 20, as shown in step 102. The mobile BTS 48 and the device 20 then establish a communication link in accordance with standard, well-known cellular protocol practices, as shown in step 104. The mobile BTS 48 then sends a "setup" request to the personal communication device 20, as shown in step 106. The mobile device 20 then acknowledges the setup request by sending an "alert" message back to the BTS 48, as shown in step 108. When the mobile device 20 goes off-hook, it sends a "connect" message to the BTS 48, as shown in step 110. A session between the user of the personal communication device 20 and the calling party then subsequently occurs, as shown in step 112.

The system and method of the present invention thus form a means by which to place a mobile platform upon which to place a mobile platformOr each personal communication device of each user located at a remote location outside their cellular service provider's coverage area, may establish a cellular communication link. Importantly, the system is not limited to accessing only one cellular device provider, but rather allows any practical number of cellular service providers to participate in providing services to users located remotely from the user on the mobile platform. The system and method of the present invention is also not limited to voice information, but is just as easily used to process personal communication devices 20 at the user and by the land network 16 of the present invention₁-16_nData transmission between supported terrestrial counterparts.

While various preferred embodiments have been described, it will be apparent to those skilled in the art that modifications or variations can be made without departing from the inventive concept. The examples illustrate the invention and are not intended to limit it. Accordingly, the specification and claims should be interpreted liberally with only such limitation as is necessary in view of the pertinent prior art.

Claims (10)

1. A system for providing cellular service to a plurality of individuals, at least one of said individuals being located outside the coverage area of an associated cellular service network, said system comprising:

an access segment that is sufficiently close to the individual to establish a wireless communication link with the individual's personal cellular communication device and that is used to facilitate two-way wireless communication with the device;

the access segment includes:

a base transceiver station BTS for establishing a wireless communication link with the device; and

a base station control server for managing radio resources of the BTS;

at least one terrestrial segment for interfacing with at least one terrestrial cellular service provider network over a wide area network; said terrestrial segment comprising a Visitor Location Register (VLR) database to temporarily store subscriber information associated with an individual as a valid subscriber, said VLR further operative to accept only necessary subscriber information to enable service with respect to a new foreign cellular service provider to which said individual is visiting;

a space-based repeater for relaying wireless signals between the access segment and the terrestrial segment; and is

The VLR communicates with a plurality of independent cellular service providers via the wide area network through one or more gateway interfaces, the VLR being queried to determine whether the device is currently registered with the VLR through information contained in the authentication request issued by the device.

2. The system of claim 1, further comprising a carrier terminal located proximate to said access segment for facilitating wireless communication between the access segment and said terrestrial network.

3. The system of claim 1, wherein the ground segment includes a control subsystem for controlling access to the ground segment by the ground network.

4. A system according to claim 3, wherein said control subsystem comprises a mobile switching center server for controlling authentication and registration information transmitted between said terrestrial cellular service provider network and said terrestrial segment.

5. A system according to claim 3, wherein said control subsystem comprises said visitor location register VLR, and said VLR temporarily stores information about each of said individuals received from their home wireless networks.

6. A system according to claim 3, wherein each of said individuals is located on a mobile platform or in an area remote from said coverage area of any cellular service provider; and is

The VLR temporarily stores information about the mobile platform or the area remote from the coverage area.

7. The system of claim 1, wherein the access segment comprises:

a base station control application BSC for controlling the operational characteristics of radio signals communicated between said access segment and said terrestrial segment.

8. The system of claim 1, wherein the visiting terrestrial segment is in two-way communication with a plurality of independent service providers.

9. The system of claim 1, wherein the individual is located on a mobile platform; and is

Wherein the mobile platform sends real-time location information to the visitor location register to update the visitor location register with location information associated with each of the individuals.

10. A method for establishing a cellular communication link between a plurality of electronic devices located within a geographic area and used by a plurality of individuals and a plurality of independent ground-based cellular service providers, comprising:

establishing a wireless communication link with each of the electronic devices and managing the link using an access segment having a base transceiver station and located in proximity to the electronic devices;

interfacing with the terrestrial-based cellular service provider using terrestrial segmentation;

relaying wireless signals between the terrestrial segment and the access segment to establish a wireless communication link between each of the electronic devices and the terrestrial-based cellular service provider; and is

Over a wide area network, a visitor location register in the terrestrial segment obtains subscriber information associated with each of the individuals from their corresponding terrestrial-based cellular service provider, and truncates the visitor location register to accept only the necessary subscriber information, thereby enabling service with respect to the new foreign cellular service provider that the individual is visiting.