MXPA02000964A - System and method for restricting mobility of cellular telephones. - Google Patents

Abstract

A cellular telephone is restricted to using only predetermined cells. The first time (306) the telephone is used, it learns (308) the identity of the cell which services it and stores that identity in the telephone. Thereafter, a request (314) to be serviced by a cell whose identity is not stored in the telephone will be denied (316) unless it is to the service provider or to emergency personnel. If it is to the service provider, then the service provider can determine (318) whether the requested cell should be in the telephone as an approved cell.

Description

-9 SYSTEM. AND METHOD TO RESTRICT MOBILITY OF CELL PHONES BACKGROUND OF THE INVENTION 5 I. Field of the Invention The present invention relates to the cellular telephone service, and more particularly to controlling the effective mobility of a cellular telephone. 10 II. Related Technique A significant advantage with cellular telephone technology is that it provides user mobility. The user can travel and use a cell phone in any area with service by a provider of 15 cellular service. In some situations, such as for each of the remote locations or in the newly developed nations with minimal existing telephone service, cellular technology is selected since it is less expensive to install than a landline system 20 that requires expensive installation of copper wiring. In such a situation, the cellular service provider intends that the cell phone be used in the same way as a conventional metallic line telephone, that is, in a fixed place.

However, there is little that can be done to prevent the use of such a cell phone as a mobile device. If the phone can be provided with an adequate power source, the user can travel with the phone and use it freely since the device uses cellular technology. However, the telephone is intended for use as a wireline telephone at a fixed location, and the subscriber is billed only for such use. Typically, metal line rates are lower than cellular (mobile) rates. The mobile operation is not displayed by the cellular service provider, and the subscriber is not billed at mobile rates. There is therefore a need for a system and method for restricting the mobility of such a telephone, so that a user can only use the device in a relatively limited geographical area, as intended by the cellular service provider. This can prevent the use of the device in a mobile way for which the subscriber is not billed.

SUMMARY OF THE INVENTION The present invention provides a system and method by which a cellular service provider can control the mobility of a cell phone that is normally treated as a metallic line telephone for billing purposes. The cell phone must identify which cells can be accessed directly from a certain fixed location, such as a user's home. For purposes of this discussion, a cell phone can have direct access to a cell if the telephone can establish radio frequency useful (RF) contact with the cell without requiring any intervention relay. The identities of the directly accessible cells are recorded in a section of the cell phone memory known hereinafter as the cellular buffer. The subsequent use of the cell phone in metal line rates can only occur if the cell phone is in a geographical region determined by these cells, known hereinafter as the local region of the telephone. In one embodiment of the invention, for example, the local region comprises those locations to which the cellular telephone has direct access to any of the cells installed in its cellular buffer. If the cell phone is not in the local region, cell phone use is prevented in metal line billing rates. In one embodiment of the invention, cell phone operation is allowed outside of the local region, but only in cell billing rates. In another embodiment of the invention, cell phone operation outside the local region is completely prevented.

Characteristics and advantages The present invention has the characteristic of allowing a cell phone to identify and register the cells to which it can directly access. The present invention has the additional feature of allowing the determination of a local region for the cellular phone. The present invention has the additional feature of affecting the operability of the cellular phone or changing its billing rate outside of the local region. The present invention has the advantage of allowing a cellular service provider to control the effective mobility of a cellular telephone. The present invention has the additional advantage of having flexibility of implementation. The invention can be implemented in software, hardware or a combination thereof.

BRIEF DESCRIPTION OF THE FIGURES The foregoing and other features and advantages of the invention will become apparent from the following more particular description of a preferred embodiment of invention, as illustrated in the accompanying drawings. FIGURE 1 illustrates a portion of an exemplary cellular communication system. FIGURE 2 illustrates an exemplary cellular buffer, according to one embodiment of the invention. FIGURE 3 is a flow chart illustrating the processing of a cellular telephone call and the decision process with respect to the ability to afford the call, in accordance with one embodiment of the invention. FIGURE 4 illustrates a cellular telephone in contact with one of the cells identified in its cellular buffer, according to one embodiment of the invention. FIGURE 5 illustrates a cellular telephone in contact with an unidentified cell in its cellular buffer, according to one embodiment of the invention. FIGURE 6 is a flow chart illustrating the process of directly identifying the accessible cells and registering their identities, according to one embodiment of the invention.

FIGURE 7 is a flow chart illustrating the processing of a cellular transfer, according to one embodiment of the invention. FIGURE 8 illustrates a generic computer system that can be used to perform the operations of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES I. General Review The present invention provides a system and method by which a cellular service provider can control the mobility of a cellular telephone. To do this, the cell phone must identify to which cells it can have direct access from a certain fixed location, such as a user's home or office. This fixed place is known from now on as the local place. The identities of the directly accessible cells are recorded in a portion of the cell phone memory, known as a cellular buffer. Subsequent use of the telephone may only occur if the cell phone is in a geographical region determined by these cells. For purposes of this discussion, this geographic region is known as the local region. Methods by which such a local region can be determined are described below. If the cell phone is not in your local region, cell phone usage is prevented at normal metal billing rates. In one embodiment of the invention, cell phone operation is allowed outside of this region, but only in cellular billing rates. In another embodiment of the invention, cell phone operation outside of this region is completely prevented.

II. Apparatus The present invention operates in the context of a cellular telephone system, the general architecture of which is known to those skilled in the art. A portion of an exemplary cellular telephone system is illustrated in FIGURE 1. A cellular telephone 101 is displayed in a location where it can reach any of the cells 102, 104 and 106 directly. Once in contact with a cell, the cellular telephone 101 can place or receive a call through the cellular system, through that cell. Note that at any given time there will be cells that are not accessible by the cellular phone. A cell 108 is such a cell. As will be described below, cells that can be accessed directly by cellular telephone 101 from a local location (such as a user's home or office) are used to determine a local region. It is within the local region that the cellular telephone 101 can operate at normal metal line billing rates, in accordance with the present invention. Contained within the cellular telephone 101 is a cellular intermediate memory which is used to register the identities of cells that can be accessed directly by the cellular telephone 101. FIGURE 2 illustrates such a buffer. A cellular intermediate memory 202 comprises a plurality of memory locations, illustrated as memory locations 204A to 204H. The memory locations 204A to 204C contain identifiers 102, 104, and 106 respectively. These identifiers correspond to the cells directly accessible by the cellular telephone 101 from their local place.

III. Process The process of the present invention requires that a cell phone learns the identities of accessible cells from a defined location. The use of the cell phone in metal line billing rates is allowed only if the cell phone is in a local place determined by these cells. If the cell phone has moved to a location outside of this local region, cell phone use is not allowed in metal line billing rates.

A. Call placement The process of the invention, according to one embodiment, is described in greater detail in FIGURE 3. In a step 304, the user attempts to place a call from a certain location using a cellular telephone. In a step 306, the process asks if this is the first call originated by the cell phone. If so, in a step 308, the cell phone must learn the identities of the cells to which it can directly access. These learning processes are described below. Once the learning process is completed, in a step 310 the user can proceed with the call. Note that in an alternative embodiment of the invention, the learning process can occur as soon as the cell phone is turned on, even before any attempt to place a call. If, in step 306 it is determined that this is not the first call, then the learning process must have previously occurred. In this case, a set of cell identifiers will have already been stored in the cell phone cellular buffer. In the embodiment of the invention illustrated in FIGURE 3, the operation of the cellular telephone in metal line rates is allowed only if one or more of the calls identified in the cellular buffer is directly accessible by the cellular telephone. In a step 312, therefore, the process asks whether any of the cells listed in the cellular buffer is accessible by the cell phone from its current location. If so, the call may proceed in step 310. If none of the cells listed in the cellular buffer is accessible by the cell phone, then the cell phone must have moved some distance from its local place, where it had initially performed stage 308 of learning. Normally, a call in this situation can be denied by the present invention. One embodiment of the invention, however, is an exception to calls to the cellular service provider and emergency calls, for example 911. Therefore, in a step 314, the process asks if the call is being answered. made to the cellular service provider. If not, then in a step 316 the call is denied, in accordance with one embodiment of the invention. If the call is directed to the cellular service provider, the call is allowed in a step 317. The cellular service provider must then decide, in a step 318, whether the apparent relocation of the cell phone should be authorized. If relocation is authorized, then the cell phone must undergo a learning process 319, identical to the learning process 318, to learn the identities of the cells accessible by the cell phone from its new location. If the relocation is not authorized in step 318, then processing is stopped. FIGURE 4 illustrates the situation where one of the cells originally listed in the cellular buffer is directly accessible by the cell phone. Here the cellular telephone 101 can have direct access to cell 102, which is one of the cells whose identifier is recorded in the cellular buffer. In such a situation, a call placed by cellular telephone 101 will be allowed according to an embodiment of the invention illustrated in FIGURE 3. FIGURE 5 illustrates the situation where none of the cells originally listed in the cellular buffer is directly accessible by cellphone. Here the cell phone 101 can directly access only cell 108, which is not one of the cells whose identifier was recorded in its cellular buffer. In such a situation, a call placed by the cellular telephone 101 will not be allowed unless the call is directed to the cellular service provider, in accordance with an embodiment of the invention shown in FIGURE 3. Note that in other embodiments of the invention , an unauthorized call will not be denied (that is, a call placed by the cell phone while it is outside the local region and directed to another party different from the cellular service provider). In an alternative mode, a call will be allowed, but will be billed at cellular rates, instead of metal line rates. In addition, in alternative embodiments of the invention, the local region can be determined in different ways from that described in the above with respect to FIGURE 3. For example, the local region can comprise the locations of which all the cells identified in FIG. the cellular buffer, instead of just one cell, are directly accessible. In this case, the operation not restricted in metal line rates is only allowed if all the cells in the cellular buffer are directly accessible by the cell phone. Alternatively, the local region may comprise the locations of which a certain predetermined subset of cells is directly accessible. Direct access to any of the two cells identified in the cellular buffer, for example, may be required before the unrestricted operation on wireless rates is allowed. In another alternative embodiment, a cellular telephone is considered to be in the local region unless a cell not listed in the cellular buffer is directly accessible. In this case, direct access to some other cell not listed in the cellular buffer means that the cell phone is no longer in the local region. In yet another alternative mode, a cellular phone is considered to be in the local region as long as the signals of the cells identified in the cellular buffer are strong enough. Here, the reception of a weak signal from a cell identified in the cellular buffer means that the cell phone has been diverted out of the local region, and the unrestricted operation in wireless rates will not be allowed.

B. Call reception The processing for receiving calls is completely analogous to that of call placement. The reception of a call in wireless billing rates is allowed if the cell phone is in a local region determined by the cells identified in the cellular buffer. If the cell phone has moved to a location outside of this local region, receiving a call at metal line billing rates is not allowed. Note that in one embodiment of the invention, an exception is made for calls that originate from the cellular service provider. Here, the reception of such calls will be allowed in metal line rates regardless of the location of the cell phone.

C. Learning The invention requires that the cell phone be able to register the identities of cells that can be accessed directly from an ada location. This learning process is illustrated in FIGURE 6. In a step 604, the cellular buffer of a cellular telephone is erased. In a step 606, the process asks if any new cell, that is, one not currently listed in the cellular buffer, is directly accessible by the cell phone. If such cells do not exist, then the processing ends in a step 607. If such a cell exists, then in a step 608 the process asks if the cellular buffer is currently full. If the cellular buffer is full, then no further cellular identifiers can be added to the cellular buffer, and the processing ends in step 607. If the cellular buffer is not full, then, in a step 610, the identifier of the cell is added to the cellular buffer. The process is then repeated with step 606. The learning process continues until no more accessible cells are found or the cellular buffer is filled.

D. Transfer A special problem can arise if the cell phone originates a call from a place in the local region, then moves to another place during the call, so that a cellular transfer is required. The invention handles this upon termination of the call or change to cell billing rates if the new cell (to which the transfer will be made) is not identified in the cellular buffer. The process for dealing with a transfer problem is illustrated in FIGURE 7. In a step 704, the process asks whether a transfer is required. If so, in a step 706, the process asks whether the identifier of the newly accessible cell (to which the connection is about to pass) is listed in the cellular buffer. If this cell is not listed in the cellular buffer, then the call is terminated in a step 708. In an alternative mode, the call will proceed in this situation, but at cellular rates. If, as determined in step 706, the newly accessible cell is listed in the cellular buffer, then the transfer proceeds in a step 710. In a step 712, the call proceeds.

IV. Environment The present invention is preferably implemented in software. Alternatively, the invention can be implemented using hardware or a combination of hardware and software. Accordingly, the invention can be implemented in a computerized system or other processing system. An example of such a computerized system 800 is shown in FIGURE 8. The computerized system 800 includes one or more processors, such as the processor 804. The processor 804 is connected to a communication infrastructure 806 (e.g., a bus or network). Several software implementations are described in terms of this exemplary computer system. After reading this description, it will become apparent to someone with experience in the relevant art how to implement the invention using other computerized systems and / or other computerized architectures. The computerized system 800 also includes a main memory 808, preferably a random access memory (RAM) and may also include a secondary memory 810. The secondary memory 810 may include, for example, a hard disk drive 812 and / or a removable storage unit 814, which represents a flexible disk drive, or a magnetic tape drive, an optical disk drive, etc. The removable storage unit 814 reads from and / or writes to a removable storage unit 818 in a well-known manner. The removable storage unit 818 represents a flexible disk, a magnetic tape, an optical disk, etc., which is read by and written to the removable storage unit 814. As will be appreciated, the removable storage unit 818 includes a storage medium that is used by computer that is stored in the same computer software and / or data. In alternative implementations, secondary memory 810 may include other similar means to allow computer programs or other instructions to be loaded into the computerized system 800. Such means may include, for example, a removable storage unit 822 and an interface 820. Examples of such means may include a program cartridge and a cartridge interface (such as that found in video game devices), a chip removable memory (such as an EPROM, or PROM) and associated socket, and other removable storage units 822 and interfaces 820 that allow software and data to be transferred from the removable storage unit 822 to a computerized 800 system. The computerized system 800 may also include a communications 824 interface. The communications interface 824 allows software and data to be transferred between the computerized 800 system and external devices. Examples of communication interface 824 may include a modem, a network interface (such as an Internet card), a communication port, a PCMCIA slot and card, etc. The software and the data transferred through the communication interface 824 are in the form of signals 828 which may be electronic, electromagnetic, optical or other signals capable of being received by the communication interface 824. These signals 828 are provided to the communication interface 824 via a communications path 826. The communication path 826 carries the signals 828 and can be implemented using a wire or cable, optical fibers, a telephone line, a cellular telephone link, an RF link and other communication channels. In this document, the terms "computerized program means" and "means that can be used by computer" are used to refer generally to means such as the removable storage unit 814, a hard disk installed in the hard drive 812, and the signals 828. These computer program products are means for providing software to the computerized system 800. Computer programs (also called computer control logic) are stored in main memory 808 and / or secondary memory 810. Computer programs can also be received through the communication interface 824. Such computerized programs, when executed, allow the computerized system 800 to implement the present invention as discussed herein. In particular, computer programs, when executed, allow the processor 804 to implement the process of the present invention. Accordingly, such computerized programs represent controllers of the computerized 800 system. In a preferred embodiment of the invention, the process in which a cell phone is allowed (or denied), the placing or receiving of a call, learns and records the identities of the accessible cells, and performs cell transfers, all of which are performed by the computerized control logic. Where the invention is implemented using the software, the software can be stored in a computer program product and loaded into a computerized system 800 using the removable storage unit 814, and the hard drive unit 812 or the communications interface 824.

V. Conclusion While various embodiments of the present invention have been described in the foregoing, it should be understood that they have been presented by way of example and not limitation. It will be apparent to persons with experience in the relevant art that several changes in detail can be made in the present without departing from the spirit and scope of the invention. Thus, the present invention should not be limited by any of the exemplary embodiments described above, but should be defined only in accordance with the following claims and their equivalents.

Claims (21)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and therefore the property described in the following claims is claimed as property. 1. A method for restricting the mobility of a cellular telephone in a cellular communication system, the method is characterized in that it comprises the steps of: (a) identifying the cells that are directly accessible by the cellular telephone, when the cellular telephone is in a place local; (b) recording the identities of the cells in an internal cellular buffer in the cell phone; and (c) prevent the cell phone from operating at predetermined metal line rates when the cell phone is outside a local region determined by the cells. 2. The method of compliance with the claim 1, characterized in that step (c) comprises: (i) preventing the placement of outgoing calls in parts other than that of the cellular service provider or emergency agency when the cell phone is outside the local region; (ii) prevent incoming calls from parties other than the cellular service provider or from an emergency agency when the cell phone is outside the local region; (iii) allow the placement of outgoing calls when the cell phone is in the local region; (iv) allow the reception of incoming calls when the cell phone is in the local region. 3. The method of compliance with the claim 1, characterized in that step (c) comprises: (i) allowing the placement of outgoing calls regardless of the location of the cell phone; (ii) invoice in predetermined metallic line rates for outgoing calls placed when the cell phone is in the local region; (iii) invoicing at predetermined cellular rates for outgoing calls placed when the cell phone is not in the local region; (iv) allow the reception of incoming calls regardless of the location of the cell phone; (v) invoicing in predetermined metallic line rates for incoming calls received when the cell phone is in the local region; (vi) invoicing at predetermined cellular rates for incoming calls received when the cell phone is not in the local region. The method according to claim 1, characterized in that step (c) comprises terminating an outgoing call when the cellular phone attempts to transfer to an unidentified cell in the cellular buffer. The method according to claim 1, characterized in that step (c) comprises billing for the outgoing call at the predetermined cellular rates when the cell phone attempts to transfer to unidentified cells in the cellular buffer. 6. The method of compliance with the claim 1, characterized in that the local region comprises geographic locations from which the cellular telephone can directly access a subset of cells whose identities are recorded in the cellular buffer, where the subset is of a predetermined size that is smaller than the number total of cells of operation in a cellular communications system. The method according to claim 1, characterized in that the local region comprises geographical locations from which the cellular telephone can directly access all the cells whose identities are recorded in the cellular buffer. The method according to claim 1, characterized in that the local region comprises geographic locations from which the cellular telephone can have direct access in at least one of the cells whose identities are recorded in the cellular buffer. 9. The method according to claim 1, characterized in that the local region comprises geographical locations where: (i) all the cells whose identities are recorded in the cellular buffer are directly accessible by the cell phone; and (ii) the signals coming from the cells received by the cell phone have a resistance to the signals greater than or equal to a predetermined minimum signal strength. 10. The method according to claim 1, characterized in that the local region comprises geographic locations where, apart from the cells whose identities are recorded in the cellular buffer, no other cell is directly accessible by the cell phone. 11. A system for restricting the mobility of a cellular telephone in a cellular communication system, the system is characterized in that it comprises: (i) identifying means to identify cells that are directly accessible by the cellular telephone when the cellular telephone is in a local place; (ii) registering means for registering identities of the cells in an internal cellular buffer in the cell phone; and (iii) prevention means to prevent the cellular telephone from operating at predetermined metal line rates when the cellular telephone is outside a local region determined by the cells. The system according to claim 11, characterized in that the means of prevention comprises: (i) placement of prevention means to prevent the placement of outgoing calls to parties other than that of the cellular service provider or 911 when the cell phone be outside the local region; (ii) receipt of prevention means to prevent incoming calls from parties other than those of the cellular service provider and 911 when the cell phone is outside the local region; (iii) the local region placement allows means to allow the placement of outgoing calls when the cell phone is in the local region; and (iv) means that allow the reception of the local region to allow reception of incoming calls when the cellular telephone is in the local region. The system according to claim 11, characterized in that the means of prevention comprises: (i) means that allow placement to allow placement of outgoing calls regardless of the location of the cell phone; (ii) outgoing metal line billing means for billing at predetermined metal line rates for outgoing calls placed when the cell phone is in the local region; (iii) outgoing cell billing means for billing at predetermined cellular rates for outgoing calls placed when the cell phone is not in the local region; (iv) means that allow reception to allow reception of incoming calls regardless of the location of the cellular telephone; (v) incoming metal line billing means for billing at predetermined metal line rates for incoming calls received when the cellular telephone is in the local region; (vi) incoming cell billing means for billing at predetermined cellular rates for incoming calls received when the cell phone is not in the local region. The system according to claim 11, characterized in that the prevention means comprises means for terminating the transfer to terminate an outgoing call when the cellular telephone attempts to transfer to an unidentified cell in the cellular buffer. The system according to claim 11, characterized in that the prevention means comprises cell transfer billing means for billing the outgoing call at the predetermined cellular rates when the cellular phone attempts to transfer to the unidentified cell in the cellular buffer . The system according to claim 11, characterized in that the local region comprises geographic locations from which the cellular telephone can directly access a subset of cells whose identities are recorded in the cellular buffer, where the subset is a predetermined size that is less than the total number of operating cells in a cellular communications system. The system according to claim 11, characterized in that the local region comprises geographic locations from which the cellular telephone can directly access all the cells whose identities are recorded in the cellular buffer. 18. The system according to claim 11, characterized in that the local region comprises geographical locations from which the cellular telephone can have direct access in at least one of the cells whose identities are recorded in the cellular buffer. 19. The system according to claim 11, characterized in that the local region comprises geographical locations where: (i) all the cells whose identities are recorded in the cellular buffer are directly accessible by the cell phone; and (ii) the signals coming from the cells are received by the cellular phone having a signal strength greater than or equal to a predetermined minimum signal strength. 20. The system according to claim 11, characterized in that the local region comprises geographic locations, where apart from the cells whose identities are recorded in the cellular buffer, no other cell is directly accessible by the cell phone. 21. A computer program product comprising a computer-usable medium having program code means that can be viewed by computer modified in the medium to cause an application program to run on a computer that restricts mobility of a cellular telephone in a cellular communications system, the program code means that can be viewed by computer is characterized in that it comprises: (a) a first program code means that can be read by computer to cause the computer to identify Cells that are directly accessible by cell phone when the cell phone is in a local place; (b) a second means of program code that can be viewed by computer to cause the computer to register the identities of the cells in an internal cellular buffer in the cell phone; and (c) a third program code means that can be viewed by computer to cause the computer to prevent the cell phone from operating at predetermined metal line rates when the cell phone is outside a local region predetermined by the cells.