Apparatus and method for controlling communications in a multi-network, wireless communication system

• US 5,920,818 A
• Filed: 12/03/1996
• Issued: 07/06/1999
• Est. Priority Date: 12/03/1996
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Kronestedt, Fredric Carl Ulf, Wiorek, Jonas Lennart, Dannelind, John Tomas Robert, Wallstedt, Yngve Kenneth, Frodigh, Carl Magnus, Olofsson, H.ang.kan Gunnar
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): Jama, Isaak R.
• Application Number:
  US08/759,939
• Time in Patent Office: 945 Days
• Field of Search: 455/76, 455/15, 455/436, 455/437, 455/411, 455/11.1, 455/439, 455/445, 455/449, 455/433, 455/440, 455/426, 455/441, 455/444, 455/524, 455/525, 455/560, 455/554, 455/421 , 455/443, 342/457, 371/5.1, 371/5.5, 370/331
• US Class Current: 455/443
• 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 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/322 by location data

Abstract

Apparatus, and an associated method, controls operation of a mobile terminal operable in a communication system having two network portions. Selective permission of cell selection of communications between the two network portions better assures that the mobile terminal, when positioned in an area intended to be encompassed by one of the network portions, communicates with that network portion.

Claims

1. A method of selectively permitting and prohibiting cell selection of a communication with a mobile terminal between a first wireless network and a second wireless network each network comprising at least one base station transceiver, said method comprising the steps of:

appointing an area covered by one base station transceiver of one network as a gateway area between the first and second networks;

determining whether or not the mobile terminal is located within the gateway area;

permitting cell selection of the communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the mobile is within the gateway area; and

prohibiting cell selection of the communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the mobile terminal is outside the gateway area.

2. A method according to claim 1 wherein said step of determining comprises the steps of:

transmitting radio signals from the mobile terminal;

receiving by at least two base transceivers in at least one of the first and second networks, said radio signals transmitted from the mobile terminal; and

comparing at least one characteristic of the signals received by the at least two base transceivers.

3. A method according to claim 2 for cellular network portions comprising cells determined by the base transceivers, wherein as gateway area is appointed an area comprising at least part of one cell but not all cells.

4. A method according to claim 3 wherein the step of permitting comprises:

arranging neighbor cell lists;

permitting a first cell of one network constituting at least part of the gateway area to appear on a neighbor cell list of a second cell of the other network; and

permitting cell selection between the second cell and the first cell appearing on the neighbor cell list of the second cell.

5. A method according to claim 4 wherein the step of prohibiting comprises:

prohibiting a third cell of one network not constituting part of the gateway area to appear on the neighbor cell list of the second cell of the other network; and

prohibiting cell selection between the second cell and the third cell not appearing on the neighbor cell list of the second cell.

6. A method according to claim 1 wherein said step of determining comprises the steps of:

transmitting radio signals from at least two base transceivers in at least one of the first and second networks;

receiving at the mobile terminal the radio signals transmitted from said at least two base transceivers; and

comparing at least one characteristic of the signals received by the mobile terminal.

7. A method according to claim 6 for cellular network portions comprising cells determined by the base transceivers, wherein as gateway area is appointed an area comprising at least part of one cell but not all cells.

8. A method according to claim 7 wherein the step of permitting comprises:

arranging neighbor cell lists;

permitting a first cell of one network constituting at least part of the gateway area to appear on a neighbor cell list of a second cell of the other network; and

permitting handover from the second cell to the first cell appearing on the neighbor cell list of the second cell.

9. A method according to claim 8 wherein the step of prohibiting comprises:

prohibiting a third cell of one network not constituting part of the gateway area to appear on the neighbor cell list of the second cell of the other network; and

prohibiting handover from the second cell to the third cell not appearing on the neighbor cell list of the second cell.

10. A method according to claim 1 wherein the second wireless network comprises at least two cells within the second area, wherein the gateway area appointed during said step of appointing is formed of one of the cells of the second wireless network, wherein said method comprises the further step of:

arranging neighbor cell lists for the cells of the second network wherein only cells of the second network are permitted on the neighbor cell lists of the second network cells outside the gateway area;

wherein a handover of said communication from a given one of the second network cells to a cell appearing on the neighbor cell list of the given second network cell is permitted; and

wherein a handover of said communication from the given one of the second network cells to a cell not appearing on the neighbor cell list of the given cell is prohibited.

11. A method according to claim 10 wherein the first wireless network portion comprises a cell within the first area, and wherein:

the first network cell is permitted to appear on the neighbor cell list of a second network cell within the gateway area;

a neighbor cell list is arranged for the cell of the first network;

the second network cell within the gateway area is permitted to appear on the neighbor cell list of the first network cell;

a second network cell outside the gateway area is prohibited to appear on the neighbor cell list of the first network cell;

wherein a handover of said communication from the first network cell to a cell appearing on its neighbor cell list is permitted; and

wherein a handover of said communication from the first network cell to a cell not appearing on its neighbor cell list is prohibited.

12. A method according to claim 1 for a second wireless network having as base transceivers at least two antennas connected to a hub, wherein a possible location of the mobile terminal within the second area is determined by receiving signals from the mobile terminal by the antennas, and comparing the signals received by different antennas at the hub.

13. A method of selectively permitting and prohibiting a handover of a communication with a mobile terminal between a first wireless network and a second wireless network, each network comprising at least one base station transceiver, said method comprising the steps of:

appointing one base station transceiver of one network as a gateway transceiver between the first and second networks;

determining whether or not the mobile terminal is located within an area covered by said gateway transceiver;

permitting said handover of said communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the mobile is within the area covered by said gateway transceiver; and

prohibiting said handover of said communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the mobile terminal is outside the area covered by said gateway transceiver.

14. A method according to claim 13 wherein said step of determining comprises the steps of:

transmitting radio signals from the mobile terminal;

receiving by at least two base transceivers at least one of which is said gateway transceiver radio signals transmitted from the mobile terminal; and

comparing at least one characteristic of the signals received by the at least two base transceivers.

15. A method according to claim 14 wherein said permitting is done by permitting said handover from said gateway transceiver of one network and allowing handover from a base transceiver of one network to said gateway transceiver of the other network.

16. A method according to claim 15 wherein said prohibiting is done by prohibiting said handover from a non-gateway base transceiver of one network to a non-gateway base transceiver of the other network.

17. A method according to claim 13 wherein said step of determining comprises the steps of:

transmitting radio signals from at least two base transceivers at least one of which is said appointed gateway transceiver;

receiving at the mobile terminal radio signals transmitted from said at least two base transceivers; and

comparing at least one characteristic of the signals received by the mobile terminal.

18. A method according to claim 17 wherein said permitting is done by permitting said handover from said gateway transceiver of one network to a base transceiver of the other network and allowing said handover from a base transceiver of one network to said gateway transceiver of the other network.

19. A method according to claim 18 wherein said prohibiting is done by prohibiting said handover from a non-gateway base transceiver of one network to a non-gateway base transceiver of the other network.

20. In a method for communicating in a communication system having a first wireless network permitting a mobile terminal to communicate therewith when positioned in a first area, the first area intended to be encompassed by the first wireless network and a second wireless network permitting the mobile terminal to communicate therewith when positioned in a second area, the second area intended to be encompassed by the second wireless network, an improvement of a method for selectively permitting cell selection of a communication with the mobile terminal between the first and second wireless networks, respectively, each network comprising at least one base station transceiver, said method comprising the steps of:

detecting when the mobile terminal is positioned at a selected gateway area, the selected gateway area defining a gateway between the first wireless network and the second wireless network, the selected gateway area being an area covered by one base station transceiver of one network;

generating a signal indicative of detection during said step of detecting the position of the mobile terminal at the selected gateway area;

permitting the cell selection of the communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the signal indicative of the position of the mobile terminal at the gateway area is generated during said step of generating; and

, otherwise

prohibiting the cell selection of the communication with the mobile terminal between a cell within the first wireless network and a cell within the second wireless network.

21. In a communication system having a first wireless network permitting a mobile terminal to communicate therewith when positioned in a first area having at least one cell, the first area intended to be encompassed by the first wireless network and a second wireless network permitting the mobile terminal to communicate therewith when positioned in a second area having at least one cell, the second area intended to be encompassed by the second wireless network, and improvement of apparatus for selectively permitting cell selection of a communication with the mobile terminal between the first and second wireless networks, respectively, each network comprising at least one base station transceiver, said apparatus comprising:

at least one detector for detecting when the mobile terminal is positioned at a selected gateway area, the selected gateway area defining a selected gateway between the first wireless network and the second wireless network, the gateway area being an area covered by one base station transceiver of one network, said at least one detector further for generating a signal indicative of detection of the position of the mobile terminal at the selected gateway area; and

a controller coupled to receive the signal indicative of the position of the mobile terminal at the gateway area, said controller for permitting the cell selection between a cell within the first wireless network and a cell within the second wireless network when the signal indicative of the position of the mobile terminal at the gateway area is received thereat and for prohibiting the cell selection between a cell within the first wireless network and a cell within the second wireless network if the controller fails to receive the signal indicative of the position of the mobile terminal at the selected gateway area.

22. The apparatus of claim 21 wherein the communication system comprises a cellular communication system having a first base station, a second base station, and a third base station, the first base station forming a portion of the first wireless network and defining a first cellular area, the second base station forming a first portion of the second wireless network and defining a second cellular area, and the third base station forming a second portion of the second wireless network and defining a third cellular area, the third cellular area including the selected gateway area defining the selected gateway, and wherein said detector comprises the third base station.

23. The apparatus of claim 28 wherein the cellular communication system further comprises a base station controller and wherein said controller coupled to receive the signal indicative of the position of the mobile terminal comprises at least a portion of the base station controller of the cellular communication system.

24. The apparatus of claim 23 wherein the cell selection comprises a handover of ongoing communications by the mobile terminal between the first and second wireless networks, wherein said base station controller maintains a neighbor cell list associated with each of the first base station, the second base station, and the third base station, each neighbor cell list for identifying base stations to which ongoing communications with the base station to which the neighbor cell list is associated are eligible to be handed off.

25. The apparatus of claim 24 wherein only the neighbor cell list associated with the third base station forming said detector includes identification of the first and second base stations to which ongoing communications with the third base station are eligible to be handed off.

26. The apparatus of claim 24 wherein the neighbor cell list associated with the second base station includes identification of only the third base station to which ongoing communications with the second base station are eligible to be handed off.

27. The apparatus of claim 24 wherein the second base station further comprises a plurality of distributed antenna devices coupled thereto, the distributed antenna devices distributed about a subsystem area, and the second cellular area encompassing at least a first portion of the subsystem area.

28. The apparatus of claim 21 wherein the communication system comprises a cellular communication system, the first wireless network comprises a macrocellular network having at least one base station, and the second wireless network comprises a microcellular network having a central unit and a plurality of spaced-apart, remote antenna devices coupled thereto, and wherein said detector comprises a selected remote antenna device of the spaced-apart remote antenna devices of the spaced-apart remote antenna devices of the microcellular network.

29. The apparatus of claim 28 wherein said controller comprises the central unit of the microcellular network.

30. The apparatus of claim 29 wherein the remote antenna devices generate signals of signal characteristics indicative of the position of the mobile terminal within the area encompassed by the microcellular network, said controller permitting the communication to be handed-off between the microcellular network and the macrocellular network only when the signal generated by the selected remote antenna device indicates the position of the mobile terminal more proximate thereto than any other one of the remote antenna devices.

31. The apparatus of claim 28 wherein the mobile terminal performs mobile assisted handoff measurements and generated mobile-generated signals indicative thereof, and wherein said selected remote antenna device further provides indications of the mobile-generated signals received thereat to said controller.

32. An assembly for selectively permitting and prohibiting a handover of a communication with a mobile terminal from a first wireless network and a second wireless network, each network comprising at least one cell having a base station transceiver, said assembly comprising:

a detector positioned at, and defining a gateway area covered by one base station transceiver of the second wireless network;

a determiner coupled to receive indications of detection by said detector of positioning of the mobile terminal within the gateway area; and

a handover controller operably responsive to determinations of said determiner, said handover controller for permitting said handover of said communication with said mobile terminal between a cell within the first wireless network and a cell within the second wireless network when the mobile terminal is determined to be within the gateway area and for prohibiting said handover of said communication with said mobile terminal between a cell within the first wireless system portion and a cell within the second wireless system portion when the mobile terminal is outside the gateway area.