Enhanced call delivery system for roaming cellular subscribers

• US 5,497,412 A
• Filed: 04/07/1994
• Issued: 03/05/1996
• Est. Priority Date: 04/07/1994
• Status: Expired due to Fees

• Current Assignee: Syniverse Technologies Incorporated (Syniverse Corp.)
• Original Assignee: GTE Telecommunications Services Incorporated
• Inventors: Hammer, Kenneth W., Didion, Edward L., Lannen, Margaret
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Chernoff, Michael B.
• Application Number:
  US08/224,457
• Time in Patent Office: 698 Days
• Field of Search: 379/58, 379/59, 379/60, 379/63, 455/33.1, 455/33.2, 455/54.1, 455/54.2, 455/56.1
• US Class Current: 455/432.2
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 8/06 Registration at serving network Location Register, VLR or user mobility server

Abstract

A system for enhanced call delivery to a roaming cellular subscriber, enabling said subscriber to receive calls placed to his MIN in his home system service area, utilizes a central telecommunications system processor capable of handling network applications, directly connected to a plurality of mobile telephone switches located in the service areas of a plurality of cellular telephone systems, each of said switches connected via a direct communication link to said central telecommunications system processor. A plurality of registers in said central telecommunications system processor are provided for storing data bases of system information, individual switch information, and subscriber information. The central telecommunications system processor is programmed to communicate with said switches, and to provide to the switches of the home and visited service areas of a roaming cellular subscriber: (1) making the identity of the current visited system switch of a roaming cellular subscriber known to his home system; (2) establishing financial responsibility of the roaming cellular subscriber; (3) establishing a valid roamer service profile in a visited system; and (4) setting up call delivery to a validated roaming cellular subscriber in the service area of a visited switch. The system further includes a general location register in said central telecommunications system processor containing a data base of all information necessary for validating and locating of known roamers, and a data base of routing information for location of home carriers, whereby end-to-end validation and registration is accomplished for previously unknown roamers. The system provides call delivery information to the home switch of a roamer, routing information for forwarding calls to said roamer; and a temporary directory number as needed for forwarding calls to said roamer over the Public Switched Telephone Network (PSTN).

Claims

1. An enhanced call delivery system, Follow Me Roaming Plus (FMR Plus), for delivering telephone calls to a roaming cellular subscriber, enabling said subscriber to receive calls placed to his MIN in his home system service area, said enhanced system having seamless interoperability with call delivery systems which do not participate in said enhanced call delivery system, comprising:

a central telecommunications system processor capable of handling network applications for said enhanced call delivery system;

a plurality of mobile telephone switches located in the service areas of a plurality of cellular telephone systems which participate in said enhanced call delivery system, each of said mobile telephone switches connected via a direct communications link to said central telecommunications system processor;

a plurality of registers in said central telecommunications system processor for storing data bases of system information, individual switch information, and subscriber information, said registers including;

a general location register in said central telecommunications system processor, said general location register containing a data base of all information necessary for validation of known roamers, whereby validation and registration is accomplished without reference to the home switch;

a home location register within said general location register containing a data base of all information necessary for communication with all cellular switches of all cellular providers in said network;

a visiting location register within said general location register containing a data base of all information necessary for communication with all roaming cellular subscribers registered in said system;

a data base of routing information for location of home carriers in said general location register, whereby end-to-end validation and registration can be accomplished for previously unknown roamers;

an Input/Output Gateway (FIG) to and from said central telecommunications system processor for translation of messages and inter-system communication with the host processor of cellular systems which participate in a second call delivery system, Follow Me Roaming (FMR), having a subset of the features of said enhanced system;

at least one intersystem gateway to and from said central telecommunications system processor for translation of messages and inter-system communication with cellular systems which participate in at least one third call delivery system;

means to enable said central telecommunications system processor of said enhanced call delivery system to communicate with each of said switches of said enhanced system, and through said gateways to the central processors of said second and third call delivery systems, and through said central processors to individual switches of said second and third call delivery systems, to provide to the switches of the home and visited service areas of a roaming cellular subscriber;

(1) the identity of the current visited system switch of a roaming cellular subscriber known to his home system;

(2) the financial responsibility of the roaming cellular subscriber;

(3) a valid roamer service profile in said visited system; and

(4) call delivery to a validated roaming cellular subscriber in the service area of said visited switch.

2. The system of claim 1 wherein said means to communicate with each of said switches in each of said call delivery systems comprises:

a database having information about each switch in each call delivery system, including the type of switch, which messages are supported by said switch, how each switch handles messages;

a set of Mobile Application Part (MAP) messages to control transaction flow processing within said enhanced call delivery system, and between said enhanced call delivery system and said second and third call delivery systems;

means to interpret each of said MAP messages and to discover its origin and destination; and

means to encode/decode messages to/from said second and third call delivery systems through said gateways;

whereby said enhanced call delivery system communicates seamlessly with said second and third call delivery systems.

3. A method for enhanced call delivery, for delivering telephone calls to a roaming cellular subscriber, enabling said subscriber to receive calls placed to his MIN in his home system service area, having seamless interoperability with call delivery systems which do not participate in an enhanced call delivery system, comprising:

connecting a plurality of mobile telephone switches located in the service areas of a plurality of cellular telephone systems which participate in an enhanced call delivery system, via a direct communications link to a central telecommunications system processor;

storing in said central telecommunications system processor for storing data bases of system information, individual switch information, and subscriber information;

storing a data base of routing information for location of home carriers in a general location register in said database, whereby end-to-end validation and registration can accomplished for previously unknown roamers;

providing an Input/Output Gateway to and from said central telecommunications system processor for translation of messages and intersystem communication with the host processor of cellular systems which participate in a second call delivery system, having a subset of the features of said enhanced system;

providing at least one intersystem gateway to and from said central telecommunications system processor for translation of messages and intersystem communication with cellular systems which participate in at least one third call delivery system;

enabling said central telecommunications system processor of said enhanced call delivery system to communicate with each of said switches of said enhanced system, and through said gateways to the central processors of said second and third call delivery systems, and through said central processors to individual switches of said second and third call delivery systems, to provide to the switches of the home and visited service areas of a roaming cellular subscriber;

(1) the identity of the current visited system switch of a roaming cellular subscriber known to his home system;

(2) the financial responsibility of the roaming cellular subscriber;

(3) a valid roamer service profile in said visited system; and

(4) call delivery to a validated roaming cellular subscriber in the service area of said visited switch.

4. The system of claim 3 wherein the step of enabling said central telecommunications system processor of said enhanced call delivery system to communicate with each switch in each call delivery system further comprises:

storing a database having information about each switch in each call delivery system, including the type of switch, which messages are supported by said switch, how each switch handles messages;

providing a set of Mobile Application Part (MAP) messages to control transaction flow processing within said enhanced call delivery system, and between said enhanced call delivery system and said second and third call delivery systems;

interpreting each of said MAP messages to discover its origin and destination; and

encoding/decoding messages to/from said second and third call delivery systems through said gateways;

whereby said enhanced call delivery system communicates seamlessly with said second and third call delivery systems.