Mobility management method for delivering calls in a microcellular network

• US 5,521,961 A
• Filed: 02/25/1994
• Issued: 05/28/1996
• Est. Priority Date: 03/26/1993
• Status: Expired due to Term

• Current Assignee: Tecore Incorporated
• Original Assignee: Celcore Incorporated
• Inventors: Fletcher, Anthony G., Hatcher, John L.
• Primary Examiner(s): Bost, Dwayne D.
• Application Number:
  US08/201,971
• Time in Patent Office: 823 Days
• Field of Search: 379/59, 379/60, 455/33.1, 455/33.2, 455/33.4, 455/56.1
• US Class Current: 455/444
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 60/04 using triggered events
• CPC Class Codes: H04W 68/06 using multi-step notification by changing the notification area
• CPC Class Codes: H04W 68/12 Inter-network notification
• CPC Class Codes: H04W 8/12 between location registers or mobility servers
• CPC Class Codes: H04W 88/18 Service support devices; Network management devices
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

In a method of providing cellular telephone service to a mobile telephone located in an off-load cellular telephone system adjacent to a main cellular telephone system, the mobile telephone is registered with the off-load cellular telephone system upon the mobile telephone entering the off-load cellular telephone system, and then is registered with the main cellular telephone system as being located in the off-load cellular telephone system as a function of predetermined criteria. During the time in which the mobile telephone has entered the off-load cellular telephone system but has not yet registered with the main cellular telephone system as being located in the off-load cellular telephone system, rebroadcasting page signals from main cellular telephone system into the off-load cellular telephone system ensures delivery of incoming telephone calls to the mobile telephone.

Claims

1. A method for registering a mobile telephone with an off-load cellular telephone system when the mobile telephone enters the off-load cellular telephone system from a main cellular telephone system adjacent to the off-load cellular telephone system, in order to service telephone calls to the mobile telephone, the mobile telephone having a storage location for storing and monitoring registration identification information, the method comprising the steps of:

providing an offset signal from the off-load cellular telephone system to the mobile telephone for offsetting the registration identification information stored in the storage location of the mobile telephone when the mobile telephone enters the off-load cellular telephone system from the main cellular telephone system; and

registering the mobile telephone with the off-load cellular telephone system in response to the offsetting of the registration identification information stored in the storage location of the mobile telephone.

2. The method of claim 1, wherein the off-load cellular telephone system includes a microcellular telephone system, and the main cellular telephone system includes a macrocellular telephone system.

3. The method of claim 1, wherein the registration identification information stored in the mobile telephone represents a REGID signal broadcast by the off-load cellular telephone system, the REGID signal being in accordance with EIA/TIA 553.

4. The method of claim 1, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area, and the off-load cellular telephone system includes at least one border cell having a transceiver for transmitting and receiving signals and being substantially within the signal coverage area of the at least one main cell transceiver and at least one interior cell having a transceiver for transmitting and receiving signals and being substantially outside the signal coverage area of the at least one main cell transceiver, and wherein the providing step further includes the step of:

providing the offset signal from the border cell transceiver in the at least one border cell to the mobile telephone for offsetting the registration identification information stored in the storage location of the mobile telephone.

5. The method of claim 4, wherein the offset signal is a REGINCR signal determined by the main cellular telephone system, the REGINCR signal being in accordance with EIA/TIA 553.

6. The method of claim 4, wherein the providing step further includes the step of:

providing an additional offset signal from the interior cell transceiver in the at least one interior cell to the mobile telephone for offsetting the registration identification information stored in the storage location of the mobile telephone.

7. The method of claim 6, wherein the additional offset signal is a REGINCR signal, the REGINCR signal being in accordance with EIA/TIA 553.

8. The method of claim 1, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one underlay cell having a transceiver for transmitting and receiving signals and being within the signal coverage area of the at least one main cell transceiver.

9. The method of claim 1, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one partial underlay cell having a transceiver for transmitting and receiving signals and being partially within the signal coverage area of the at least one main cell transceiver.

10. A method for registering a mobile telephone with a microcellular telephone system when the mobile telephone enters the microcellular telephone system from a macrocellular telephone system adjacent to the microcellular telephone system, in order to service telephone calls to the mobile telephone, comprising the steps of:

providing a registration signal from the microcellular telephone system to the mobile telephone when the mobile telephone enters the microcellular telephone system; and

stimulating registration of the mobile telephone with the microcellular telephone system in response to the registration signal, wherein the microcellular telephone system and the macrocellular telephone system have the same system identification signal.

11. The method of claim 10, wherein the macrocellular telephone system includes at least one macrocell having a transceiver for transmitting and receiving signals in a signal coverage area and the microcellular telephone system includes at least one border cell and at least one interior cell, the at least one border cell having a transceiver for transmitting and receiving signals and being substantially within the signal coverage area of the at least one macrocell transceiver and the at least one interior cell having a transceiver for transmitting and receiving signals and being substantially outside the signal coverage area of the at least one macrocell transceiver.

12. The method of claim 11, wherein the providing step includes the steps of:

providing a first registration signal from the at least one border cell to the mobile telephone; and

providing a second registration signal from the at least one interior cell to the mobile telephone.

13. The method of claim 12, wherein the stimulating step includes the step of:

stimulating the registration of the mobile telephone with the microcellular telephone system in response to the first and second registration signals.

14. The method of claim 10, wherein the macrocellular telephone system includes at least one macrocell having a transceiver for transmitting and receiving signals in a signal coverage area and the microcellular telephone system includes at least one underlay cell having a transceiver for transmitting and receiving signals and being within the signal coverage area of the at least one macrocell transceiver.

15. The method of claim 10, wherein the macrocellular telephone system includes at least one macrocell having a transceiver for transmitting and receiving signals in a signal coverage area and the microcellular telephone system includes at least one partial underlay cell having a transceiver for transmitting and receiving signals and being partially within the signal coverage area of the at least one macrocell transceiver.

16. A method for informing a main cellular telephone system that a mobile telephone is located in an adjacent off-load cellular telephone system, comprising the steps of:

registering the mobile telephone with the off-load cellular telephone system upon the mobile telephone entering the off-load cellular telephone system; and

registering the mobile telephone with a standard communications interface system after registering the mobile telephone with the off-load cellular system and as a function of predetermined criteria, in order to inform the main cellular telephone system that the mobile telephone is located in the off-load cellular telephone system.

17. The method of claim 16, wherein the standard communications interface system includes an EIA/TIA IS-41 Cellular Radio telecommunications Intersystem Operations interface.

18. The method of claim 16, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one border cell having a transceiver for transmitting and receiving signals and being substantially within the signal coverage area of the at least one main cell transceiver and at least one interior cell having a transceiver for transmitting and receiving signals and being substantially outside the signal coverage area of the at least one main cell transceiver, wherein the mobile telephone is located in one of the at least one border cells, and wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a telephone call attempt by the mobile telephone.

19. The method of claim 18, wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a preselected number of registrations of the mobile telephone with the at least one border cell.

20. The method of claim 16, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one border cell having a transceiver for transmitting and receiving signals and being substantially within the signal coverage area of the at least one main cell transceiver and at least one interior cell having a transceiver for transmitting and receiving signals and being substantially outside the signal coverage area of the at least one main cell transceiver, wherein the mobile telephone is located in one of the at least one interior cells, and wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a first registration attempt by the mobile telephone to register with the at least one interior cell.

21. The method of claim 16, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one underlay cell having a transceiver for transmitting and receiving signals and being within the signal coverage area of the at least one main cell transceiver, wherein the mobile telephone is located in one of the at least one underlay cells, and wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a telephone call attempt by the mobile telephone.

22. The method of claim 21, wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a predetermined number of registrations of the mobile telephone with the at least one underlay cell.

23. The method of claim 16, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one partial underlay cell having a transceiver for transmitting and receiving signals and being partially within the signal coverage area of the at least one main cell transceiver, wherein the mobile telephone is located in one of the at least one partial underlay cells, and wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a telephone call attempt by the mobile telephone.

24. The method of claim 23, wherein the predetermined criteria for registering the mobile telephone as being located in the off-load cellular telephone system includes a predetermined number of registrations of the mobile telephone with the at least one underlay cell.

25. The method of claim 16, further comprising the step of:

deregistering the mobile telephone from the standard communications interface system as a function of predetermined criteria after registering the mobile telephone with the standard communications interface system.

26. The method of claim 25, wherein the predetermined criteria for deregistering includes a completion of a telephone call by the mobile telephone.

27. The method of claim 25, wherein the predetermined criteria for deregistering includes a preselected number of missed registrations of the mobile telephone with the off-load cellular telephone system.

28. The method of claim 25, wherein the main cellular telephone system includes at least one main cell having a transceiver for transmitting and receiving signals in a signal coverage area and the off-load cellular telephone system includes at least one border cell having a transceiver for transmitting and receiving signals and being substantially within the signal coverage area of the at least one main cell transceiver and at least one interior cell having a transceiver for transmitting and receiving signals and being substantially outside the signal coverage area of the at least one main cell transceiver, wherein the mobile telephone is registered with the main cellular telephone system as being located in the off-load cellular telephone system and the mobile telephone then enters the at least one border cell of the off-load cellular telephone system, wherein the predetermined criteria for deregistering the mobile telephone with the main cellular telephone system as being located in the off-load cellular telephone system includes a first registration attempt by the mobile telephone to register with the at least one border cell.

29. A method of informing a mobile telephone located in an off-load cellular telephone system adjacent to a main cellular telephone system that there is a telephone call for the mobile telephone, comprising the steps of:

registering the mobile telephone with the off-load cellular telephone system upon the mobile telephone entering the off-load cellular telephone system;

registering the mobile telephone with a standard communications interface system, after registering the mobile telephone with the off-load cellular telephone system, as a function of predetermined criteria, in order to inform the main cellular telephone system that the mobile telephone is located in the off-load cellular telephone system;

determining whether the mobile telephone is registered with the main cellular system as being located in the off-load cellular telephone system;

if the mobile telephone is not registered with the main cellular telephone system as being located in the off-load cellular telephone system, then;

broadcasting a page signal in the main cellular telephone system when the telephone call for the mobile telephone is received by the main cellular telephone system, and

rebroadcasting the page signal originally broadcast in the main cellular telephone system into the off-load cellular telephone system, thereby informing the mobile telephone of the telephone call;

if the mobile telephone is registered with the main cellular telephone located as being in the off-load cellular telephone system, then;

informing the mobile telephone of the telephone call through a standard communications interface system.

30. The method of claim 29, wherein the standard communications interface system includes an EIA/TIA IS-41 Cellular Radiotelecommunications Intersystem Operations interface.

31. A method of delivering a telephone call to a mobile telephone located in an off-load cellular telephone system adjacent to a main cellular telephone system, comprising the steps of:

determining whether the mobile telephone is registered with the main cellular system as being located in the off-load cellular telephone system;

if the mobile telephone is not registered with the main cellular system as being located in the off-load cellular telephone system, then;

broadcasting a page signal in the main cellular telephone system when the telephone call for the mobile telephone is received by the main cellular telephone system,

rebroadcasting the page signal originally broadcast in the main cellular telephone system into the off-load cellular telephone system,

receiving a response signal from the mobile telephone acknowledging that the mobile telephone has received the page signal,

directing the mobile telephone to retune to a frequency of the main cellular telephone system, and

delivering the telephone call to the mobile telephone through the main cellular telephone system;

if the mobile telephone is registered as being in the off-load cellular telephone system, then;

delivering the telephone call to the mobile telephone through a standard intersystem communications interface system.

32. The method of claim 31, wherein the standard communications interface system includes an EIA/TIA IS-41 Cellular Radio telecommunications Intersystem Operations interface.