Handoff for cellular and internet protocol telephony

• US 20060116127A1
• Filed: 07/18/2005
• Published: 06/01/2006
• Est. Priority Date: 07/16/2004
• Status: Active Grant

• Current Assignee: Bridgeport Networks, Inc. (Alianza, Inc.)
• Original Assignee: Bridgeport Networks, Inc. (Alianza, Inc.)
• Inventors: Wilhoite, Michael T., Singh, Inderdeep, Blumenthal, Steven H.
• Granted Patent: US 7,502,615 B2
• Time in Patent Office: Days
• US Class Current: 455/442
• CPC Class Codes: H04M 2203/1091 Fixed mobile conversion
• CPC Class Codes: H04M 2207/20 hybrid systems
• CPC Class Codes: H04M 2242/30 Determination of the location of a subscriber
• CPC Class Codes: H04M 3/42246 where the subscriber uses a multi-mode terminal which moves and accesses different networks with at least one network having a wireline access including cordless PBX
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/249 according to timing information
• CPC Class Codes: H04W 36/322 by location data
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• CPC Class Codes: H04W 4/16 Communication-related supplementary services, e.g. call-transfer or call-hold
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 60/04 using triggered events
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A telephone system supports communication with user devices over both a cellular radio network as well as over an Internet Protocol (IP) network, and enables roaming and active call handoff between cellular and IP domains. Components of the system interact with conventional cellular telephone systems, for example, by emulating behavior of control components, providing proxy services for conventional components, transporting cellular telephone control communication over IP connections, or by simulating cellular operating characteristics of user devices operating in an IP domain.

Claims

1. A method for handoff of telephone sessions comprising:

maintaining an active telephone session between a mobile unit and a telephone system over the data communication system;

while maintaining the session over the data communication system, determining information associated with a radio system associated with the telephone system; and

handing off the active telephone session from the data communication system to the radio system according to the determined information.

2. The method of claim 1 wherein the information associated with the radio system includes signal characteristics on the radio system.

3. The method of claim 1 wherein the information associated with the radio system includes radio channel information for the radio system.

4. The method of claim 1 wherein the telephone system comprises a cellular telephone system.

5. The method of claim 1 wherein the data communication system comprises a data network.

6. The method of claim 5 wherein the data network comprises an Internet Protocol (IP) network.

7. The method of claim 5 wherein the data network comprises a wireless local area network.

8. The method of claim 1 further comprising, prior to maintaining the session over the data communication network:

maintaining the active telephone session between the mobile unit over a radio system of the telephone system, including receiving radio channel information at the mobile unit over the radio system;

establishing communication between the mobile unit and the telephone system over a data communication system; and

handing off the active telephone session from the radio system of the telephone system to the data communication system.

9. The method of claim 8 wherein receiving radio channel information at the mobile unit includes receiving a candidate channel list for a cellular telephone system.

10. The method of claim 9 wherein measuring the signal characteristics includes measuring signal strength characteristics for each of the channels of the candidate channel list.

11. The method of claim 10 further comprising providing the candidate channel list to the telephone system after establishing communication between the mobile unit and the telephone system, and receiving the candidate list from the telephone system prior to handing off the session from the data network to the radio system.

12. A method comprising:

coupling a mobile unit over a data network with a first device, the mobile unit being capable of communication over a radio network of a mobile telephone system; and

providing control information from the first device to the telephone system that simulates presence of the mobile unit on the radio network.

13. The method of claim 12 wherein the control information includes signal characteristics.

14. The method of claim 12 wherein the control information includes radio channel information.

15. The method of claim 12 wherein the control information includes authentication information.

16. A telecommunication device comprising:

an interface to a data network;

an interface to a telephone network;

wherein the device is configured to communicate with a mobile unit over the interface to the data network, and to simulate over the interface to the telephone network presence of the mobile unit on a radio network of the telephone system.

17. A method comprising:

concurrently maintaining communication between a mobile unit and a telephone system over a radio system of the telephone system and over a data communication system coupled to the telephone system;

measuring signal characteristics based on communication with the mobile unit over the radio system;

computing simulated signal characteristics associated with communication with the mobile unit over the data communication system; and

providing the simulated signal characteristics to the telephone system.

18. The method of claim 17 further comprising providing the measured signal characteristics in conjunction with the simulated signal characteristics.

19. The method of claim 17 further comprising:

controlling association of the mobile unit with one of the radio system and the data communication system according to the provided signal characteristics.

20. The method of claim 19 wherein computing the simulated signal characteristics includes computing the simulated characteristics to affect association of the mobile unit with one of the radio system and the data communication system.

21. The method of claim 20 wherein computing the simulated signal characteristics includes computing the simulated signal characteristics to be superior to the measured signal characteristics to control the association of the mobile unit with the data communication system.

22. A method comprising:

communicating telephone system control information between a dual-mode device and the telephone system, including passing the telephone control information over a data network encapsulated in a data network communication protocol; and

performing a handoff of the dual mode device between the telephone system and the data network using the encapsulated telephone control information.

23. The method of claim 22 wherein the data network communication protocol includes a session control protocol.

24. The method of claim 23 wherein the session control protocol includes Session Initiation Protocol (SIP).

25. The method of claim 22 wherein the telephone system control information includes telephone system signal characteristic information.

26. The method of claim 22 wherein the telephone system control information includes telephone system radio channel information.

27. A dual mode device for communicating over a telephone system and a data network comprising:

a data network client, including components for establishing communication sessions over the data network;

a telephone system client, including components for establishing communication sessions over the telephone system; and

a service controller coupled to the data network client and to the telephone system client that enables a handoff of an active communication session between the data network client and the telephone system client.

28. The device of claim 27 wherein the data network client is configured to send and/or receive encapsulated telephone system control information, and pass the telephone control information to the service controller.

29. The device of claim 28 wherein the network client is configured to send and/or receive the telephone system control information in session control protocol messages.