Interactive roamer contact system for cellular mobile radiotelephone network

Claims

What is claimed is:

1. In a home cellular mobile radiotelephone system, an apparatus for detecting and contacting a roamer cellular mobile radiotelephone (CMR) from a foreign cellular mobile radiotelephone system, comprising:

roamer detection means for detecting autonomous registration of said roamer CMR in said first cellular mobile radiotelephone system and for providing identifying information comprising at least a mobile telephone number of said roamer CMR;

a computer database for storing the mobile telephone numbers of detected roamer CMRs in association with status information, said status information indicating whether detected roamer CMRs have never been solicited;

searching means responsive to said identifying information for searching said computer database and determining whether said roamer CMR has never been solicited;

solicitation request generating means responsive to a determination by said searching and determining means that said roamer CMR has never been solicited for generating a solicitation request; and

interactive solicitation means responsive to said solicitation request for providing an interactive solicitation of said roamer CMR.

2. The apparatus of claim 1, wherein said interactive solicitation means is operative for delivering a message to said roamer CMR and receiving responses to a message delivered to said roamer CMR.

3. The apparatus of claim 2, wherein said interactive solicitation means is operative for delivering a voice message to said roamer CMR and receiving responses via dual-tone multifrequency tones provided by a user of said roamer CMR.

4. The apparatus of claim 1, wherein said interactive solicitation means is operative for (1) placing a telephone call to said roamer CMR, and (2) delivering a voice message if the call to said roamer CMR is answered.

5. The apparatus of claim 4, wherein said interactive solicitation means is operative for (1) storing a preprogrammed voice message script corresponding to a predetermined message, (2) generating a synthesized voice corresponding to the preprogrammed voice message script, and (3) delivering the synthesized voice to said roamer CMR.

6. The apparatus of claim 1, wherein said interactive solicitation means is further operative for detecting responses from said roamer CMR, and storing the detected responses as status information in said computer database.

7. The apparatus of claim 6, wherein the detected responses includes data indicative of a successful or unsuccessful communication with said roamer CMR, and wherein said interactive solicitation means is further operative for reattempting to communicate with said roamer CMR in the event of an unsuccessful communication.

8. The apparatus of claim 6, wherein the detected responses include data indicative of a reply of a user of said roamer CMR to a communication, and further comprising means for providing the detected responses as an output.

9. The apparatus of claim 1, wherein said interactive solicitation means is operative for:

placing a telephone call to the telephone number of said roamer CMR;

responsive to a successful connection with said roamer CMR, delivering a predetermined message via a voice channel.

10. The apparatus of claim 1, wherein said interactive solicitation means is operative for:

placing a telephone call to said roamer CMR;

determining whether the telephone call was completed and setting a solicit fail flag in response to an incompleted telephone call, the solicit fail flag being associated with the mobile telephone number of said roamer CMR;

responsive to said solicit fail flag, scheduling a predetermined number of subsequent attempts to place a telephone call to said roamer CMR; and

responsive to a successful connection to said roamer CMR, delivering a predetermined voice message via a voice channel.

11. The apparatus of claim 10, wherein said interactive solicitation means is further operative for receiving dual-tone multifrequency signals provided by a user of said roamer CMR as input from the user in response to the predetermined voice message, and providing an output data item corresponding to the input received from the user.

12. The apparatus of claim 10, wherein the predetermined voice message comprises a message related to the provision of roaming services provided by the operator of said home cellular mobile radiotelephone system to roamers, and said output data item relates to the selection or rejection of roaming services by the user of said roamer CMR.

13. The apparatus of claim 1, wherein said status information indicates whether detected roamer CMRs have not been detected within a predetermined time period y,

wherein said searching and determining means is further responsive to said identifying information for determining whether said roamer CMR has not been detected within said predetermined time period y, and

wherein said solicitation request generating means is responsive to a determination by said searching and determining means that said roamer CMR has not been detected within said predetermined time period y for generating a solicitation request.

14. The apparatus of claim 1, wherein said status information indicates whether detected roamer CMRs have not been solicited within a predetermined time period z,

wherein said searching and determining means is further responsive to said identifying information for determining whether said roamer CMR has not been solicited within said predetermined time period z, and

wherein said solicitation request generating means is responsive to a determination by said searching and determining means that said roamer CMR has not been solicited within said predetermined time period z for generating a solicitation request.

15. The apparatus of claim 1, wherein said status information indicates whether detected roamer CMRs have blocked solicitations,

wherein said searching and determining means is further responsive to said identifying information for determining whether said roamer CMR has blocked solicitations, and

wherein said solicitation request generating means is responsive to a determination by said searching and determining means that said roamer CMR has blocked further solicitations for blocking generation of a solicitation request.

16. The apparatus of claim 1, wherein said roamer detection means comprises means for receiving signaling data contained in a cell-to-MTSO data link.

17. The apparatus of claim 1, wherein said roamer detection means comprises means connectable to a telephone network signaling system selected from the group comprising: IS-41, SS7, and X.25.

18. The apparatus of claim 1, wherein said roamer detection means detects autonomous registration of said roamer CMR from information received from an MTSO.

19. The apparatus of claim 1, wherein said roamer detection means detects autonomous registration of said roamer CMR within an MTSO.

20. In a home cellular mobile radiotelephone system, a method for detecting and contacting a roamer cellular mobile radiotelephone (CMR) from a foreign cellular mobile radiotelephone system, comprising the steps of:

storing in a computer database the mobile telephone numbers of detected roamer CMRs in association with status information, said status information indicating whether detected roamer CMRs have never been solicited;

detecting autonomous registration of a roamer CMR in said home cellular mobile radiotelephone system;

providing identifying information comprising at least a mobile telephone number of said roamer CMR;

searching said computer database with said identifying information to determine whether said roamer CMR has never been solicited;

in response to a determination that said roamer CMR has never been solicited, generating a solicitation request to a solicitation apparatus; and

at said solicitation apparatus, in response to said solicitation request, conducting an interactive solicitation of said roamer CMR.

21. The method of claim 20, wherein said status information indicates whether detected roamer CMRs have not been detected within a predetermined time period y, and further comprising the steps of:

determining whether said roamer CMR has not been detected within said predetermined time period y, and

responsive to a determination that said roamer CMR has not been detected within said predetermined time period y, generating a solicitation request to said solicitation apparatus.

22. The method of claim 20, wherein said status information indicates whether detected roamer CMRs have not been solicited within a predetermined time period z, and further comprising the steps of:

determining whether said roamer CMR has not been solicited within said predetermined time period z, and

responsive to a determination that said roamer CMR has not been solicited within said predetermined time period z, generating a solicitation request to said solicitation apparatus.

23. The method of claim 20, wherein said status information indicates whether detected roamer CMRs have blocked solicitations, and further comprising the steps of:

determining whether said roamer CMR has blocked solicitations, and

responsive to a determination that said roamer CMR has blocked further solicitations, blocking generation of a solicitation request.

24. The method of claim 20, further comprising the steps of delivering a message to said roamer CMR and receiving responses to a message delivered to said roamer CMR.

25. The method of claim 24, wherein the step of delivering a message to the registering mobile radiotelephone comprises delivering a voice message to said roamer CMR and receiving responses via dual-tone multifrequency tones provided by a user of said roamer CMR.

26. The method of claim 20, wherein the step of conducting an interactive solicitation of said roamer CMR comprises:

(1) placing a telephone call to said roamer CMR, and

(2) delivering a voice message if the call to said roamer CMR is answered.

27. The method of claim 26, wherein the step of generating a voice message comprises the steps of:

(1) providing a preprogrammed voice message script corresponding to a predetermined message,

(2) generating a synthesized voice corresponding to the preprogrammed voice message script, and

(3) delivering the synthesized voice to said roamer CMR.

28. The method of claim 20, further comprising the step of detecting responses from said roamer CMR, and storing the detected responses as status information in said computer database.

29. The method of claim 28, wherein the detected responses includes data indicative of a successful or unsuccessful communication with said roamer CMR, and further comprising the step of reattempting to communicate with said roamer CMR in the event of an unsuccessful communication.

30. The method of claim 28, wherein the detected responses include data indicative of a reply of a user of said roamer CMR to a communication, and further comprising the step of providing the detected responses as an output.

31. The method of claim 20, wherein the step of conducting an interactive solicitation of said roamer CMR comprises the steps of:

placing a telephone call to the telephone number of said roamer CMR;

responsive to a successful connection with said roamer CMR, delivering a predetermined message via a voice channel.

32. The method of claim 20, wherein the step of conducting an interactive solicitation of said roamer CMR comprises the steps of:

placing a telephone call to said roamer CMR;

determining whether the telephone call was completed and setting a solicit fail flag in response to an incompleted telephone call, the solicit fail flag being associated with the mobile telephone number of said roamer CMR;

responsive to said solicit fail flag, scheduling a predetermined number of subsequent attempt to place a telephone call to said roamer CMR;

responsive to a successful connection to said roamer CMR, delivering a predetermined voice message via a voice channel.

33. The method of claim 32, further comprising the steps of receiving dual-tone multifrequency signals provided by a user of said roamer CMR as input from the user in response to the predetermined voice message, and providing an output data item corresponding to the input received from the user.

34. The method of claim 32, wherein the predetermined voice message comprises a message related to the provision of roaming services provided by the operator of said first cellular mobile radiotelephone system to roamers, and said output data item relates to the selection or rejection of roaming services by the user of said roamer CMR.

35. The method of claim 20, wherein the step of detecting autonomous registration of a roamer CMR comprises receiving signaling data contained in a cell-to-MTSO data link.

36. The method of claim 20, wherein the step of detecting autonomous registration of a roamer CMR is carried out with information provided by a telephone network signaling system selected from the group consisting of: IS-41, SS7, and X.25.

37. The method of claim 20, wherein the step of detecting autonomous registration of a roamer CMR is carried out with information received from a MTSO.

38. The method of claim 20, wherein the step of detecting autonomous registration of a roamer CMR is carried out within a MTSO.

TECHNICAL FIELD

The present invention generally relates to cellular mobile radiotelephone (CMR) communication systems, and more particularly relates to methods and apparatus for automatically detecting the presence of predetermined classes of mobile radiotelephones within the cellular network, such as roamers, and for automatically and interactively communicating with a registering mobile radiotelephone within such classes. For example, the present invention is suitable for detecting roamers, placing a call to a detected roamer, providing a predetermined synthesized voice message (such as information concerning the availability of roaming services within the network), and receiving responses provided via the telephone keypad.

BACKGROUND

Cellular mobile radiotelephone (CMR) service has been in widespread use for several years. Typical systems are characterized by dividing a radio coverage area into smaller coverage areas or "cells" using low power transmitters and coverage-restricted receivers. CMR systems are described in U.S. Pat. Nos. 3,906,166 and 4,268,722. As will be known to those skilled in the art, the limited coverage area enables the radio channels used in one cell to be reused in another cell. As a cellular mobile radiotelephone within one cell moves across the boundary of the cell and into an adjacent cell, control circuitry associated with the cells detects that the signal strength of the telephone in the just-entered cell is stronger, and communications with the radiotelephone are "handed off" to the just-entered cell.

A cellular mobile radiotelephone system typically utilizes a pair of radio frequencies for each radio channel in each cell. Each cell typically includes at least one signalling channel (also called a control or access channel) and several voice channels. The signalling channel is selected or dedicated to receive requests for service from mobiles and portables, to page selected mobiles or portables, and to instruct the mobiles or portables to tune to a predetermined voice channel where a conversation may take place. The signalling channel is responsible for receiving and transmitting data to control the actions of the mobiles and portables.

The data message and radio channel specifications for U.S. cellular radiotelephone systems are set forth in Electronic Industries Association/Telecommunications Industry Association (EIA/TIA) Standard 533 (previously known as Interim Standard CIS-3) implemented in accordance with 47 C.F.R. 22, in the Report and Orders pertaining to Federal Communications Commission (FCC) Docket No. 79-318. Copies of the EIA/TIA-533 may be obtained from the Engineering Department of the Electronic Industries Association at 2001 Pennsylvania Avenue, N.W., Washington, D.C. U.S.A. 20006.

Increasingly, users of cellular mobile radiotelephones travel between cities having cellular systems operated by different operating companies. In addition, the FCC has established that each area wishing to establish a cellular telephone network may have up to two cellular system operators, and therefore parallel but separate systems are in place in most major metropolitan areas. While the mobile radiotelephones for use in these different systems are identical, the cellular systems are configured so that only cellular telephones which are identified as "home" units or subscribers within a given cellular system may communicate within a given operator's system.

It is known that when a cellular mobile radiotelephone originates a call, it transmits a series of data messages to the serving cell. These messages, referred to as a Call Origination, are defined by EIA/TIA-533. These data messages always contain the low order seven digits of the unit's telephone number, known as the Mobile Identification Number (MIN), the unit's Station Class Mark (SCM), which identifies functional characteristics of the unit, and the Called Address, or dialed telephone number. Although optional, cellular system operators typically also require additional data words to be transmitted that contain the MIN2, which is the high order three digits or NPA of the cellular unit's telephone number, and the Electronic Serial Number (ESN).

These data messages are provided first to the cell, and then through a data link to the mobile telephone switching office ("MTSO"). The MTSO, also known as "the switch", makes voice connections between mobile radiotelephones and the main telephone network. At the MTSO, a determination is typically made whether the radiotelephone is an authorized user or subscriber by looking up the telephone number, serial number, and other information provided by the radiotelephone to see if there is an entry in the MTSO's database corresponding to that particular telephone. Part of the normal, but optional, functions of an MTSO is to validate that the ESN and MIN received as part of a Call Origination message are valid. If the MIN is valid and "home", the received ESN is compared to the MTSO's database ESN entry to detect fraud. If these checks succeed, the call is allowed to proceed.

It is also known that a cellular mobile radiotelephone, when it first powers up or first enters the cell of a CMR system when already powered up, can optionally be instructed to identify itself as actively present within a particular cell and on the system. The radiotelephone identifies itself or "registers" through a process known as Autonomous Registration by providing a data packet similar to that of a Call Origination. The original design intent of Autonomous Registration was to improve the efficiency of potential future call deliveries by keeping the MTSO informed of the approximate whereabouts of each individual cellular unit, and to reduce paging channel load by lessening the need to page all cells to find a cellular unit. When the MTSO is thus informed, it can "page" (i.e., attempt to ring) the cellular unit only in the cell or area that it was last known to be in. Additional cells would be paged only if the mobile was not found with the initial page.

While most cellular systems support the Autonomous Registration feature, processing of the received identification information is usually proprietary to the vendor of the MTSO equipment. However, it will be observed that the data contained in an Autonomous Registration message is essentially the same as a Call Origination. The difference is that an Autonomous Registration is not associated with a call attempt, and is not necessarily used to validate a cellular unit's ability to place or receive calls. Instead, an Autonomous Registration is simply a set of messages periodically and autonomously sent from the mobile to the serving cell at an interval specified in data parameters previously received from the cell by the cellular unit.

For purposes of the present application, the terms "register", "registration", etc. will be used to denote the provision of identification information by Call Origination, Autonomous Registration, or other means.

It is further known that in CMR systems, a subscriber's ability to receive incoming calls outside his or her home service area is restricted. A subscriber using or attempting to use his or her cellular mobile radiotelephone in a service area outside his home service area is said to be "roaming", and he or she is commonly referred to as a "roamer". When cellular telephone subscribers leave the area of their subscribed service, they frequently do not use their cellular telephones because they do not know (or have forgotten) the particular procedures for operating their radiotelephone as a "roamer" in the newly-entered service area. Lack of use of the radiotelephone in different service areas results in a loss of the benefits of cellular telephone service to the subscriber, and a loss of revenue both from the calls that would otherwise be made by the roamer and from calls to the roamer which cannot be completed because the roamer's home service area does not know where to forward the calls.

Even though a subscriber is not always aware of having travelled beyond the range of the home service area, CMR systems are designed to detect this situation and so apprise the user, in the following manner. Each cellular system has been uniquely assigned a System IDentification (SID) number. Electrical signals corresponding to each cellular system's SID are continuously transmitted by that system over a control channel. The SID of the system from which a particular subscriber has agreed to acquire CMR services is programmed into a Numerical Assignment Module (NAM) or memory incorporated into the subscriber's mobile radiotelephone unit.

When a subscriber's mobile radiotelephone unit is "powered up" or first enters the area of coverage of a CMR system when already powered up, it selects the strongest detectable control channel and receives a system parameter overhead message in the form of an overhead message train (OMT). The OMT includes the 15-bit SID of the CMR system whose signal the mobile unit is receiving. The mobile unit then compares the transmitted SID to the SID programmed into its NAM to determine identicality. If the unit determines lack of identicality, it is indicated that the unit is "roaming". In many cellular radiotelephone units, a "roam" indicator light is activated on the control panel associated with the unit. In this manner, a subscriber is made aware that his or her mobile radiotelephone unit has seized or entered a system other than the system on which he or she is an authorized subscriber.

A roamer who desires to place an outgoing call typically must then access the CMR system in which he or she is roaming through procedures established by the CMR system operator. These procedures typically involve special codes, key sequences, and information solicitation from the subscriber so that the roamer is aware that he or she will be billed at the rates established for roaming services (instead of the usual "home" service rate).

Further difficulties are encountered when a roamer desires to receive incoming calls when in a foreign service area. In order for a roamer to receive incoming calls, it is typically required that would-be third-party callers know the whereabouts of the subscriber. Unanswered calls placed to the subscriber's home number are typically answered with a message indicating that the subscriber cannot be found. If the caller knows the CMR system in which the roamer is present, then there are procedures provided for accessing the subscriber through the facilities of that CMR system. This requires the caller to know the roamer's itinerary and the roamer access number of the CMR system in which the roamer is present. Many major service areas have a 10-digit roamer access number. Armed with this and other information, a would-be caller may dial the 10-digit roamer access number of the CMR system in which the roamer is present. Then, the caller dials the roamer's home number, including home area code, and the call will be delivered.

This unwieldy procedure can sometimes be exacerbated by the need for the subscriber to arrange the right to have incoming calls delivered with the CMR service provider in the foreign area.

Needless to say, procedures for arranging for roaming service such as these require advance planning, scheduling, and dissemination of itinerary information to persons who may want to call the subscriber in a foreign service area. These cumbersome procedures inhibit the flexibility and freedom prized by many cellular telephone s