Security cellular telecommunications system

Claims

What is claimed is:

1. A method of completing pre-paid wireless telephone calls to a subscriber, the subscriber having a prepaid subscriber account balance stored in a database, where the prepaid subscriber account balance is associated with a predetermined wireless telephone number assigned to the subscriber, comprising:

receiving the subscriber's wireless telephone number at a wireless switch, the telephone number corresponding to a wireless telecommunications event initiated by a party calling the subscriber's wireless telephone number, the wireless switch recognizing the subscriber's wireless telephone number as being associated with the subscriber;

communicating between a computer with access to the database and the wireless switch;

validating existence of a pre-determined subscriber account balance in the database; and

if the validating step is successful, completing a call.

2. The method of claim 1 comprising:

checking for a connection with the subscriber's wireless telephone, and periodically validating a call based on the balance associated with the account during the telecommunications event until the call is terminated.

3. The method of claim 2 wherein the call is terminated due to validation being unsuccessful.

4. The method of claim 2 wherein the call is terminated by a party to the call.

5. The method of claim 1 comprising:

checking for a connection with the subscriber's wireless telephone; and

causing the call to be terminated when a time limit based on the account balance is expired.

6. A method of wireless telecommunications with respect to a subscriber, the subscriber having a prepaid subscriber account balance stored in a database, where the prepaid subscriber account balance is associated with a predetermined wireless telephone number assigned to the subscriber, comprising:

receiving an identifier associated with the subscriber at a wireless switch, the wireless switch recognizing the identifier as being associated with a pre-paid subscriber for whom a wireless telecommunications event has been initiated by a party calling the subscriber's wireless telephone number;

communicating between a computer with access to the database and the wireless switch;

attempting to establish a connection between the wireless switch and the subscriber's wireless telephone;

checking for a connection with the subscriber'wireless telephone, and periodically validating a call based on the balance associated with the account during the telecommunications event until the call is terminated.

7. The method of claim 6 wherein the call is terminated due to validation being unsuccessful.

8. The method of claim 6 wherein the call is terminated by a party to the call.

9. A method of completing wireless telephone call requests to a subscriber to a pre-paid wireless telephone service, comprising:

receiving at a wireless switch an identifier corresponding to a pre-paid wireless subscriber to whom a wireless telephone call is directed;

forwarding the identifier to a pre-paid wireless service provider associated with the pre-paid wireless subscriber that validates an account associated with the pre-paid wireless subscriber based on the forwarded identifier, and if the validation is successful, passes the identifier to a wireless switch and causes the call to be completed, performs periodic real-time validation of the account while the call is in progress, and causes the call to be interrupted while the call is in progress if the periodic validation fails.

10. A method of completing wireless telephone call requests to a subscriber to a pre-paid wireless telephone service, comprising:

receiving at a wireless switch an identifier corresponding to a pre-paid wireless subscriber to whom a wireless telephone call is directed;

at a pre-paid wireless service provider associated with a pre-paid wireless subscriber to whom a wireless telephone call is directed, receiving from a telecommunications service an identifier corresponding to the pre-paid wireless subscriber;

validating an account associated with the pre-paid wireless subscriber based on the forwarded identifier;

if the validation is successful, passing the identifier to a wireless switch and causing the call to be completed;

performing periodic real-time validation of the account while the call is in progress; and

causing the call to be interrupted while the call is in progress if the periodic validation fails.

11. A method of wireless telecommunications with respect to a subscriber, the subscriber having a prepaid subscriber account balance stored in a database where the prepaid subscriber account balance is associated with a predetermined wireless telephone number assigned to the subscriber, comprising:

receiving an identifier associated with the subscriber at a wireless switch, the wireless switch recognizing the identifier as being associated with a pre-paid subscriber for whom a wireless telecommunications event has been initiated by a party calling the subscriber's wireless telephone number;

communicating between a computer with access to the database and the wireless switch;

attempting to establish a connection between the wireless switch and the subscriber's wireless telephone;

checking for a connection with the subscriber's wireless telephone, and causing a call to be terminated when a time limit based on the account balance is expired.

12. The method of claim 11 comprising:

identifying at least one cost variable associated with the call;

determining a rate associated with a fixed interval of time based on the cost variable; and

converting the account balance to a maximum call length based on the account balance and based on the rate.

13. The method of claim 12 wherein the cost variable is time of day.

14. The method of claim 12 wherein the cost variable is a destination of the pre-paid wireless call.

15. A method of completing wireless telephone call requests to a subscriber to a pre-paid wireless telephone service, comprising:

receiving at a wireless switch an identifier corresponding to a pre-paid wireless subscriber to whom a wireless telephone call is directed;

forwarding the identifier to a pre-paid wireless service provider associated with the pre-paid wireless subscriber that validates an account associated with the pre-paid wireless subscriber based on the forwarded identifier, and if the validation is successful, passes the identifier to a wireless switch, causes the call to be completed, sets a time limit based on the account balance, and causes the call to be terminated when the time limit is expired.

16. A method of completing wireless telephone call requests to a subscriber to a pre-paid wireless telephone service, comprising:

receiving at a wireless switch an identifier corresponding to a pre-paid wireless subscriber to whom a wireless telephone call is directed;

at a pre-paid wireless service provider associated with a pre-paid wireless subscriber to whom a wireless telephone call is directed, receiving from a telecommunications service an identifier corresponding to the pre-paid wireless subscriber;

validating an account associated with the pre-paid wireless subscriber based on the forwarded identifier; and

if the validation is successful, passing the identifier to a wireless switch and causing the call to be completed; and

causing the call to be terminated when a time limit based on the account balance is expired.

17. A system for managing pre-paid wireless communications, comprising:

a wireless switch at which a wireless call request is received; and

a pre-paid wireless service provider, in communication with the wireless switch, that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and

wherein validation of an account by the pre-paid wireless service provider occurs periodically during a call and the call is caused to be terminated if validation is unsuccessful.

18. A method for managing pre-paid wireless communications, comprising:

receiving a wireless call request at a wireless switch; and

communicating between the wireless switch and a pre-paid wireless service provider that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed; wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and wherein validation of an account by the pre-paid wireless service provider occurs periodically during a call and the call is caused to be terminated if validation is unsuccessful.

19. A method for managing pre-paid wireless communications, comprising:

at a pre-paid wireless service provider, communicating with a wireless switch at which a wireless call request is received, and selectively authorizing the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and

wherein validation of an account by the pre-paid wireless service provider occurs periodically during a call and the call is caused to be terminated if validation is unsuccessful.

20. A system for managing pre-paid wireless communications, comprising:

a wireless switch at which a wireless call request is received; and

a pre-paid wireless service provider, in communication with the wireless switch, that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom to call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and

wherein validation of an account by the pre-paid wireless service provider includes causing a call is caused to be terminated when a time limit based on a balance in the account is expired.

21. A method for managing pre-paid wireless communications, comprising:

receiving a wireless call request at a wireless switch; and

communicating between the wireless switch and a pre-paid wireless service provider that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed; wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and wherein validation of an account by the pre-paid wireless service provider includes causing a call to be terminated when a time limit based on a balance in the account is expired.

22. A method for managing pre-paid wireless communications, comprising:

at a pre-paid wireless service provider, communicating with a wireless switch at which a wireless call request is received, and selectively authorizing the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account associated with the identified pre-paid wireless subscriber; and

wherein validation of an account by the pre-paid wireless service provider includes causing a call to be terminated when a time limit based on a balance in the account is expired.

23. A system for managing pre-paid wireless communications, comprising:

a wireless switch at which a wireless call request is received; and

a pre-paid wireless service provider, in communication with the wireless switch, that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the wireless call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account balance associated with the identified pre-paid wireless subscriber; and

wherein validation of the account balance by the pre-paid wireless service provider occurs prior to a call being authorized.

24. A method for managing pre-paid wireless communications, comprising:

receiving a wireless call request at a wireless switch; and

communicating between the wireless switch and a pre-paid wireless service provider that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed; wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account balance associated with the identified pre-paid wireless subscriber; and wherein validation of the account balance by the pre-paid wireless service provider occurs prior to a call being authorized.

25. A method for managing pre-paid wireless communications, comprising:

at pre-paid wireless service provider, communicating with a wireless switch at which a wireless call request is received, and selectively authorizing the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed;

wherein the pre-paid wireless service provider selectively authorizes the wireless call request by validating in real time an account balance associated with the identified pre-paid wireless subscriber; and

wherein validation of the account balance by the pre-paid wireless service provider occurs prior to a call being authorized.

26. A system for managing pre-paid wireless communications comprising:

a wireless switch at which is received a wireless call request;

a pre-paid wireless service provider, in communication with the wireless switch, that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the wireless call request is directed; and

a database of pre-paid wireless subscribers, comprising account information for the pre-paid wireless subscribers, that is accessed by the pre-paid wireless service provider to decide whether to authorize the wireless call request;

the pre-paid wireless service provider's selective authorization of the wireless call request being based on a real-time validation of an account balance associated with the identified pre-paid wireless subscriber.

27. A method for managing pre-paid wireless communications, comprising:

receiving a wireless call request at a wireless switch; and

communicating between the wireless switch and a pre-paid wireless service provider that selectively authorizes the wireless call request based on information in the wireless call request that identifies a pre-paid wireless subscriber to whom the call request is directed, and that accesses a database of pre-paid wireless subscribers, comprising account information for the pre-paid wireless subscribers, in order to decide whether to authorize the wireless call request, the pre-paid wireless service provider's selective authorization of the wireless call request being based on a real-time validation of an account balance associated with the identified pre-paid wireless subscriber.

28. A method for managing pre-paid wireless communications, comprising:

at a pre-paid wireless service provider, communicating with a wireless switch at which a wireless call request is received, and selectively authorizing the wireless call request based on information in the wireless call request that identifies a subscriber to whom the call request is directed; and

accessing a database of pre-paid wireless subscribers, comprising account information for the pre-paid wireless subscribers, in order to decide whether to authorize the wireless call request, the pre-paid wireless service provider's selective authorization of the wireless call request being based on a real-time validation of the of an account balance associated with the identified pre-paid wireless subscriber.

29. A method for pre-paid wireless telephone service, the method comprising:

identifying an originator of a wireless telephone call as a subscriber to a pre-paid wireless telephone service;

causing the call to be connected to a pre-paid switching system; and

a wireless switch sending an identifier associated with the destination of the call and an identifier associated with a pre-paid account of the originator of the call to the pre-paid switching system that validates the balance in the account of the originator of the call, causes the call to be connected to the destination, sets a time limit based on the account balance, and causes the call to be terminated when the time limit is expired.

30. A method for pre-paid wireless telephone service, the method comprising:

at a pre-paid switching system, receiving from a wireless switch an identifier associated with a destination of a wireless telephone call, and an identifier associated with a pre-paid account of an originator of the call, the originator of the call being identified as being a subscriber to the pre-paid wireless telephone service;

validating the balance in the account of the originator of the call;

causing the call to be connected to the destination; and

periodically validating the call based on the balance associated with the account and causing the call to be terminated if validation is unsuccessful.

31. A method for pre-paid wireless telephone service, the method comprising:

at a pre-paid switching system, receiving from a wireless switch an identifier associated with a destination of a wireless telephone call, and an identifier associated with a pre-paid account of an originator of the call, the originator of the call being identified as being a subscriber to the pre-paid wireless telephone service;

validating the balance in the account of the originator of the call;

causing the call to be connected to the destination; and

causing the call to be terminated when a time limit based on the balance in the account is expired.

32. A method for pre-paid wireless telephone service, the method comprising:

identifying an originator of a wireless telephone call as a subscriber to a pre-paid wireless telephone service;

causing the call to be connected to a pre-paid switching system; and

sending an identifier associated with the destination of the call and an identifier associated with a pre-paid account of the originator of the call to the pre-paid switching system that validates the balance in the account of the originator of the call, causes the call to be connected to the destination, and periodically validates the call based on the balance associated with the account and terminates the call if validation is unsuccessful;

wherein the identifier associated with the pre-paid account is an electronic serial number.

33. A system for providing pre-paid wireless telephone service, comprising:

(a) a database of information pertaining to subscribers to the pre-paid wireless telephone service;

(b) a computer with access to the database of information pertaining to subscribers to the pre-paid wireless telephone service, which computer receives, from a wireless switch, an identifier associated with a destination of a wireless telephone call, and an identifier associated with a pre-paid account of an originator of the call, the originator of the call being identified as being a subscriber to the pre-paid wireless telephone service;

(c) a computer that receives information from the wireless switch and that:

(i) validates a balance in the pre-paid account of the originator of the call;

(ii) causes the call to be connected to the destination;

(iii) periodically validates the call based on the balance associated with the account; and

(iv) causes the call to be terminated if validation is unsuccessful.

34. A system for providing pre-paid wireless telephone service, comprising:

(a) a database of information pertaining to subscribers to the pre-paid wireless telephone service;

(b) a computer with access to the database of information pertaining to subscribers to the pre-paid wireless telephone service, which computer receives, from a wireless switch, an identifier associated with a destination of a wireless telephone call, and an identifier associated with a pre-paid account of an originator of the call, the originator of the call being identified as being a subscriber to the pre-paid wireless telephone service;

(c) a computer that receives information from the wireless switch and that:

(i) validates a balance in the pre-paid account of the originator of the call;

(ii) causes the call to be connected to the destination;

(iii) sets a time limit based on the account balance; and

(iv) causes the call to be terminated when the time limit is expired.

35. A method for pre-paid wireless telephone service comprising:

receiving an identifier associated with a pre-paid account of an originator of a call at a wireless switch;

at the wireless switch, determining whether the identifier is associated with a pre-paid account; and

if the identifier is associated with a pre-paid account, communicating with a pre-paid service provider and causing the identifier associated with the pre-paid account and an identifier associated with a destination of the call to be sent to the pre-paid service provider.

36. A method as set forth in claim 35 and including:

at the pre-paid service provider, validating the call based on the balance associated with the account;

causing the call to be completed; and

periodically validating the call based on the balance associated with the account and causing the call to be terminated if validation is unsuccessful.

37. The method as set forth in claim 36 wherein the step of periodically validating the call continues until the call is terminated or the balance in the account reaches a predetermined amount.

38. The method as set forth in claim 36 including terminating the call when the balance in the account reaches a predetermined amount.

39. The method of claim 35 comprising:

at the pre-paid service provider, validating the call based on the balance associated with the account;

causing the call to be completed; and

causing the call to be terminated when a time limit based on the account balance is expired.

40. The method as set forth in claim 35 wherein the step of determining whether the identifier is associated with a pre-paid account comprises accessing a database remote from the pre-paid service provider and comparing the identifier with numbers stored in the database.

41. The method as set forth in claim 40 wherein the accessing step includes sharing access to the database with other pre-paid service providers.

42. A method for pre-paid wireless telephone service, the method comprising:

identifying an originator of a wireless telephone call as a subscriber to a pre-paid wireless telephone service;

causing the call to be connected to a pre-paid switching system; and

a wireless switch sending an identifier associated with the destination of the call and an identifier associated with a pre-paid account of the originator of the call to the pre-paid switching system that validates the balance in the account of the originator of the call, causes the call to be connected to the destination, and periodically validates the call based on the balance associated with the account and causes the call to be terminated if validation is unsuccessful.

43. The method as set forth in claim 42 including terminating the call when the balance in the account becomes zero.

44. The method of claim 42 wherein the identifier associated with the pre-paid account is a mobile identifier.

45. The method of claim 42 wherein the identifier associated with the pre-paid account is a telephone number.

46. The method of claim 42 wherein the identifier associated with the pre-paid account is an automated number identifier.

47. The method as set forth in claim 42, 29, 30, or 31 wherein the validating step includes finding the pre-paid account of the originator of the call and retrieving a balance associated with the account.

48. The method as set forth in claim 47 including maintaining a database of identifiers associated with pre-paid wireless telephone accounts, the database being remote from the pre-paid switching system, and the finding step including accessing the database via a remote server.

49. The method as set forth in claim 48 wherein the accessing step includes sharing access to the database with one or more other pre-paid switching systems.

50. The method as set forth in claim 42, 29, 30, or 31 including notifying the originator of the pre-paid wireless telephone call of the status of the account.

51. The method of claim 50 including notifying the originator of the pre-paid wireless telephone call of the remaining balance.

52. The method of claim 42, 29, 30, or 31 wherein the identifier associated with the pre-paid account is an electronic serial number.

53. The method of claim 42, 29, 30, or 31 comprising:

identifying at least one cost variable associated with the call;

determining a rate associated with a fixed interval of time based on the cost variable; and

converting the account balance to a maximum call length based on the account balance and based on the rate.

54. The method of claim 53 wherein the cost variable is time of day.

55. The method of claim 53 wherein the cost variable is a destination of the pre-paid wireless call.

56. The method as set forth in claim 42, 29, 30, or 31 wherein the originator of the wireless telephone call is identified as a subscriber to the pre-paid wireless telephone service at the wireless switch.

57. The method as set forth in claim 42, 29, 30, or 31 wherein the identifier associated with the destination of the call is entered by the subscriber prior to origination of the wireless telephone call, and the identifier associated with the pre-paid account of the originator of the call is transparently sent to the wireless switch upon origination of the wireless telephone call.

58. The system of claim 33 to 34 wherein the computer with access to the database is the computer that receives information from the wireless switch, validates the balance, causes the call to be connected to the destination, periodically validates the call, and causes the call to be terminated if validation is unsuccessful.

59. The system of claim 33 to 34 wherein the computer with access to the database is networked to a server computer with which the database is associated.

BACKGROUND OF THE INVENTION

The present invention relates generally to a cellular telecommunications system having a security feature which allows only pre-authorized users to complete cellular telephone calls. More particularly, the cellular telecommunications system of the present invention permits cellular telecommunications providers to obtain pre-paid subscribers and eliminate credit-risk problems. In addition, the present invention provides anti-fraud protection for cellular service providers by allowing subscribers to designate protection codes which must be dialed before a telecommunications event will be completed.

Conventional cellular telecommunications systems require the cellular provider to undertake credit screening and certify credit-worthy subscribers before enabling a user to access the cellular telecommunications system. Customarily, a potential subscriber will apply to the cellular service provider, who then undertakes a verification process to determine whether the potential subscriber is credit-worthy. If the potential subscriber has a positive credit rating, the subscriber is given access to the cellular system and is able to initiate or receive unlimited cellular telecommunications events during a certain period of time or during a certain number of billing cycles. If the subscriber regularly pays invoices for the telecommunications services, the subscriber's access to the telecommunications system continues unfettered. If the subscriber fails to pay invoices as they become due, the cellular service provider has the ability to discontinue the subscriber's access until the invoice is paid. Thus, pre-paid telecommunications access is a desirable feature to prevent fraudulent use of the telecommunications system. Additionally, the present invention provides anti-fraud capabilities by requiring that a pass-code or personal identification number (PIN) be dialed along with the called number before a telecommunications event will be completed.

Up to now, the cellular service provider had no means available to offer cellular telecommunications services on a pre-paid basis, monitor the subscriber's cellular telecommunications usage in real time and discontinue access to the cellular telecommunications services immediately upon exhaustion of a pre-paid account balance. Additionally, up to now, cellular service providers had no means available to prevent cellular theft by unscrupulous persons retrieving equipment serial numbers from cellular signal transmissions and "cloning" or reprogramming other cellular equipment to replicate a subscriber's telecommunications profile.

DESCRIPTION OF THE PRIOR ART

Land-based telecommunication systems have devised a method for allowing pre-paid telephone usage and limiting telecommunications usage to only a period of time equivalent to the pre-paid value. Perhaps the best example of such a land-based telecommunications system is found in U.S. Pat. No. 5,353,335 issued Oct. 4, 1994 to D'Urso (hereinafter the "D'Urso" patent).

The D'Urso patent discloses a public switched telephone network (PTSN) which operates on a pre-payment system and has multilingual capabilities. A telephone user purchases a pre-determined quantum of service, i.e., telecommunications time before access and is provided a card imprinted with a unique account number. The user is also given a series of toll free, commonly known as "1-800" numbers which allows the user to access the prepaid telephone system. Activation of each of the toll free numbers causes the system described in the D'Urso patent to interact wit the user in the user's native language or in a language which the user desires to interact with the telecommunications system. Upon dialing an appropriate toll free telephone number at a PTSN node, the user is connected through a switching system with a host computer. The host computer prompts the user, typically by digital voice commands, to enter the user's account number, using the PTSN node keypad, imprinted on the user's account card. The authenticity of the entered account number and the available amount of credit is determined by the host computer. Account authentication and credit balance checking is accomplished by local area network connection with a service management computer which manages a card database containing account information for each outstanding account card. If the account card is valid and an available balance is verified, the host computer prompts the user to enter a speed dialing alias or destination telephone number. The user is given a pre-set number of attempts to enter a valid alias or destination number. The system performs editing checks on the alias or destination number. Improper entry of a speed dialing alias or destination for the pre-set number of attempts will cause the host computer to disconnect the user. Upon proper entry of a speed dialing alias or destination number, the host computer compares the available card balance against the balance required to make a one minute phone call to the desired destination. If the available balance is greater than or equal to the balance required to make that one minute call, a voice response unit (VRU) plays an announcement in the user's chosen language informing the user that the call is being processed. The VRU computer uses a stored call rate associated with the caller's destination number and the available credit balance to determine the available call duration. A call duration timer is set in response to the determination of the available call duration.

The VRU computer is then directed to outpulse the digits of the destination number to a network node. When the host computer detects an off-hook condition from the destination, the call duration timer is started and the available call balance is depleted while the call is in progress. When the host computer detects that the available call balance is close to depletion, the VRU computer is bridged onto the call and plays a pending disconnect announcement in the users chosen language. Upon exhaustion of the call balance, the VRU plays a disconnect announcement, the call is disconnected and the host computer sends a message to the service management computer and database that the balance on the card is depleted.

Alternatively, if an on-hook condition at the destination occurs before the card balance is depleted, the host computer calculates the remaining available balance based upon the condition of the call timer and compares the computed balance to the minimum credit threshold. The host computer then causes a VRU computer to notify the caller, in the chosen language, whether the remaining balance exceeds the minimum credit threshold, and the value of the available balance and then disconnects the calling party. The host computer then sends an update message to the service management computer and the database, notifying them of the calculated remaining balance. The service management computer then overwrites the present balance in the database with the calculated balance sent by the host computer.

While the D'Urso telecommunications system allows for pre-paid telecommunications activity, it is wholly dependent upon user first calling a toll free number, inputting account information, waiting for account validation, inputting the called destination, waiting for destination validation and then either being connected or not. The D'Urso system requires a plurality of input events by the user before a call can be passed to the destination. Moreover, the D'Urso system lacks direct interface with the remote database for real time account balance adjustment during a telecommunications event. Rather, in the D'Urso system a host computer queries a remote management server database to determine an available credit balance. The host computer then looks up a telecommunications rate for the destination number called, calculates a time value corresponding to the credit balance for the destination number and either authorizes or rejects the attempted call on the basis of the calculated time value. If the attempted call is authorized, a calculated time value timer is set. Upon occurrence of an off-hook condition at the destination called, the calculate time value timer at the host computer is decremented until a pre-determined threshold value. As the threshold value is reached, a voice message is bridged onto the call to advise the user of the remaining calculated time value. Upon expiration of the calculated time value, the call is disconnected. After disconnection due to either 1) expiration of the calculated time value, or 2) an on-hook condition at the called destination, the host computer re-calculates the credit balance from the remaining time value and sends an update record to the management server and database and overwrites the previous credit balance information stored at the database. In this manner, the database is not actively updated as the telecommunications activity is occurring.

Those skilled in the art will understand and appreciate that the prepaid land-based telecommunications system described in the D'Urso patent is fundamentally different from the cellular-based telecommunications system of the present invention.

SUMMARY OF THE INVENTION

A need has been recognized for a cellular telecommunications system which permits access by pre-paid users, without the need for modifying the cellular radiotelephones commonly in use. The present invention provides a system and method which recognizes cellular radiotelephones pre-programmed with a pre-selected telephone number and a automated number identification code (ANI). The pre-selected telephone number is reserved to the pre-paid cellular telecommunications system. The user merely enters the destination telephone number and activates an off-hook condition, typically by depressing a "send" button on the keypad of the cellular radiotelephone. The cellular radiotelephone then transmits the ANI and a dialed number identification system code (DNIS). Because all cellular systems operate on the basis of discrete cell sites, which re-transmit the received signal to a central cellular service organization cellular switch, both the ANI and the DNIS are transmitted to the cellular switch. At the cellular switch, the ANI is recognized as one reserved to the pre-paid cellular system and is re-directed, along with the DNIS, to the pre-paid cellular system switch via T1 land lines or via cellular re-transmission.

At the pre-paid cellular system switch, a host computer authenticates both the ANI and DNIS. Upon recognition of a valid ANI, the host computer establishes communications via either a local area network (LAN) or wide-area network (WAN) with a remote computer database server. At the remote computer database server, a database is maintained with pre-paid subscriber information. The pre-paid subscriber database contains records of each pre-paid subscriber. Each subscriber record in the database includes, at least the ANI assigned to that pre-paid subscriber, a pre-paid account balance and a time rate for telecommunications charges.

The host computer validates the received ANI by comparison to the ANI information in the database. Upon validation of the received ANI, account balance information for the account associated with the received ANI is queried to determine if there is a positive credit balance. Upon verification that the account has a positive credit balance, the host computer outpulses the dialed destination telephone number to a local exchange carrier, such as one of the Regional Bell Operating Companies.

During the call progress, the account balance information at the computer database server is decremented based upon elapse of pre-determined time periods at the predetermined time value for cellular telecommunications. It is important to note the time value is deducted from the account balance at regular intervals of time while the call is in progress.

The present invention allows a pre-paid user to access the cellular telecommunication system and have authentication and accounting occur transparently without any preliminary input by the user. The present invention accomplishes this by using the ANI as the file link to identify and authenticate the cellular telephone against the database. Thus, cellular telephone users are freed of the need to carry and use cards, are freed of the need to enter account information as a first step in the authentication process and the possibility of fraud on the cellular service providers is minimized.

These and other objects, features, and advantages of the present invention will become more apparent to those skilled in the art from the following more detailed description of the present invention when taken with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic view of a typical cellular telecommunications system interfaced with the cellular telecommunications system of the present invention.

FIG. 2 is a diagrammatic call flow of the prior art pre-paid land-based telecommunications system.

FIG. 3 is a call flow diagram from a typical cellular radiotelephone.

FIG. 4 is a call flow diagram at a cellular switch in accordance with the present invention.

FIG. 5 is a flow diagram illustrating call validation processing at a host computer in accordance with the present invention.

FIG. 6 is a flow diagram illustrating call processing at the central office in accordance with the present invention.

FIG. 7 is a flow diagram illustrating call accounting processing at a host computer in accordance with the present invention.

FIG. 8A is a flow diagram illustrating a first embodiment of incoming call processing in accordance with the present invention.

FIG. 8B is a flow diagram illustrating a second embodiment of incoming call processing in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The prepaid cellular telecommunications system of the present invention is best illustrated with reference to the accompanying drawings in which FIGS. 1 and 3 through 8B generally describe the system of the present invention and FIG. 2 depicts the prior art system described in the D'Urso patent.

With particular reference to FIG. 1, the pre-paid cellular system 10 of the present invention is illustrated. The pre-paid cellular system 10 interfaces with a conventional cellular telecommunications switched network 2. Conventional cellular telecommunications switched network 2 is a network consisting of a plurality of cellular antennae 4 capable of receiving cellular band RF signals 5, with each of the plurality cellular antennae 4 being associated with a discrete cell site 6. Each of the plurality of cellular antennae 4 is electrically linked to a cellular switch 8 which governs the operation of the cellular telecommunications switched network 2 and links the network 2 to a local exchange carrier 20 via T1 land line 12.

In accordance with the present invention, a cellular service provider 14 is linked to he cellular telecommunications switched network 2 cellular switch 8 via T1 land line 15. The cellular service provider 14 has a plurality of cellular telephone numbers reserved to it for pre-paid subscribers. Each reserved cellular telephone number has a unique automated number identifier (ANI) associated with the reserved telephone number. These reserved cellular telephone numbers are stored in a switch computer resident at switch 8. The cellular service provider 14 is electrically linked to the local exchange carrier 20 via T1 land line 17 to communicate cellular telephone calls from the service provider 14 to the local exchange carrier's regular network.

The service provider 14 has host computer 16 which is preferably networked through either a local area network (LAN) or wide area network (WAN) 21 to a remote server computer 18. In this manner a plurality of service providers may, within a single cellular service, operate from the same remote server computer 18. The remote server computer 18 has an associated database 19 of pre-paid subscribers, which is independently accessible by each of the service providers.

The host computer is preferable based upon a multi-processor platform such as those made by Intel Corporation and based upon the 486 of PENTIUM microprocessor, with each host computer having a plurality of modem's and network interface circuit boards capable of simultaneous bi-directional processing of telecommunications data between the T1 land line 15 and the modems and between the host computer and the remote server. The remote server is also preferably a multi-processor based platform capable of distributed load processing, and fitted with a plurality of network interface circuit boards. The database is preferably stored across a plurality of hard disk drives configured as a redundant array of independent drives (RAID).

In the foregoing manner, a cellular transmission 5 received by an antenna 4 within a cell size 6 is received at switch 8. If the ANI and DNIS transmitted with the cellular transmission 5 is one of the reserved pre-paid cellular telephone numbers, the switch 8 re-directs the transmission 5 to the service provider via the T1 land line 15. The transmission 5 is communicated to the service provider's host computer 16, which then authenticates the ANI and DNIS by accessing the server computer 18 and database 19. Upon valid authentication of the ANI and DNIS, the subscriber identity is validated. The database 19 will have records indicative of the subscriber's account balance. A check of the subscriber's account balance in the database 19 is made to validate the presence of a pre-paid balance sufficient to supply a pre-determined quantum of telecommunications, e.g., one minute, at a predetermined telecommunications charge rate associated with both the dialed number and the time of day in which the call is placed. Upon account balance validation, the host computer 16 validates the call and passes it to the local exchange carrier 20 via the T1 land line 7.

A pre-payment telecommunications system 30 of the prior art is illustrated with reference to FIG. 2. The system 30 requires that a pre-paid user first dial a toll free access number at block 32. Upon connection with the toll free access number, the user must enter an assigned account number imprinted on a card at block 34. After the card account number is validated at block 36, a counter is set at block 44 and a check is made at block 46 to determine whether a call on the entered account is in progress. A negative validation at block 36 will cause an invalid card flag to be initiated at block 38 and an appropriate voice message from a voice response unit (VRU) announced at block 40. If an affirmative response is elicited from the check at block 46, the VRU prompts the user to enter a destination telephone number at block 48. A validation check is made at block 50 of the dialed number entered in response to the VRU prompt at block 48. If the validation check at block 50 is affirmative, a database associated with a management computer is called at block 54 and the account's records are retrieved for credit balance determination. A check is made of the credit associated with the card account to determine whether the user's account has any available credit at block 56 and whether the available credit exceeds a pre-determined minimum threshold at block 52. An additional check is made to determine whether sufficient credit in the user's account balance to pay for a threshold time value of a call, e.g., one minute, based upon a time value rate for the destination being called is determined at block 58. If the determinations made at blocks 52, 56 and 58 are affirmative the call is passed by outpulsing the dialed number at block 60. If a negative determination at any of blocks 52, 56 or 58 is made, an appropriate voice message is played by the VRU at block 40 and the user is disconnected at block 42.

Upon connection with the destination number, an off-hook condition of the destination is sensed at block 62. If an off-hook condition exists at the destination, a timer is started at block 64 which continues until an on-hook condition exists at the destination and the timer is stopped at block 66. Upon a stop timer condition at block 66, the management computer is called and updated by overwriting the user's account record with updated information based upon the elapsed time of the call and the time value of the call at block 68. The VRU then issues an appropriate voice message 40 to advise the user of the revised account balance and the user is disconnected at block 42.

As will be understood by those skilled in the art, the foregoing description of he pre-paid telecommunications system of the prior art 30 requires the user to first access a toll-free number to be linked to a host computer, and then must enter an account code and wait for validation and then enter a destination number, and wait for validation before the call is passed. The present invention operates advantageously with a cellular telecommunications system to eliminate the need for a toll free host computer to interact directly with the user, and eliminate the need for the pre-paid user to make multiple keypad entries. Rather, as will be more apparent from the following description of the preferred embodiment, the user only enters the destination number and all call processing is handled by the host computer in conjunction with the cellular switch.

Turning now to FIGS. 3-8B, call flow in the pre-paid cellular telecommunications system of the present invention is illustrated. It is important to note that the cellular radiotelephones used by pre-paid subscribers are of a conventional type, without special circuitry, modification or programming. Rather, each cellular radiotelephone used by pre-paid subscribers is programmed, in the normal manner, with a pre-defined cellular telephone number reserved to the pre-paid cellular telecommunications system 10.

FIG. 3 illustrates call initiation by a pre-paid cellular telecommunications subscriber. The subscriber initiates a cellular call at block 72 by entering the destination number directly at the keypad of the cellular radiotelephone. After the subscriber enters the called number, the subscriber sends the destination number (DNIS) by activating a send key on the keypad of he cellular radiotelephone at block 74. The cellular radiotelephone then transmits the DNIS and an ANI unique to the transmitting cellular radiotelephone at block 76 as cellular signals 5 to the nearest antenna within the cell site.

FIG. 4 illustrates call processing by the cellular switch 8. The cellular switch 8 is constantly in a wait condition for receipt of cellular transmissions from a plurality of subscribers within the coverage area of the cellular switch. The cellular switch receives the transmitted DNIS at block 78 and the transmitted ANI at block 79. Upon recognition of the ANI as a unique ANI identifying a subscriber in the inventive pre-paid cellular system, the cellular switch routes the cellular call through a direct line to a host computer of the inventive cellular system at block 80 and goes off-hook to the host computer at block 82. The cellular switch then waits for receipt of a wink signal at block 84. Upon receipt of a first wink signal at block 84, the cellular switch sends the DNIS to the host computer at block 86. Upon receipt of a second wink signal at block 84, the cellular switch sends the ANI to the host computer at block 88. Those skilled in the art will under stand that the sequent