Methods and Apparatus for Neighbor Cell Range Extension

• US 20120282864A1
• Filed: 04/26/2012
• Published: 11/08/2012
• Est. Priority Date: 05/06/2011
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dimou, Konstantinos, Lindoff, Bengt, Kamuf, Matthias
• Granted Patent: US 9,451,515 B2
• Time in Patent Office: Days
• US Class Current: 455/67.14
• CPC Class Codes: H04W 16/08 Load shedding arrangements
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]

Abstract

A user equipment (UE) located in an extended-range area of a neighbor base station cell in a communication network, such as a low-power cell in a heterogeneous network, can inform its serving base station, such as a macro cell overlying the low-power cell, of the UE'"'"'s capability of canceling interference from other cells'"'"' transmissions. That capability information enables the serving cell to decide based on more information whether range extension of the neighbor cell is beneficial for a number of UEs, and can result in more efficient radio resource utilization.

Claims

1. A method of operating a serving base station for a communication network that includes the serving base station, at least one neighbor base station, and at least one user equipment (UE) located within communication range of the serving base station and the at least one neighbor base station, the method comprising:

transmitting, by the serving base station, at least one notification to inform the serving base station of interference cancellation capability of at least one UE and of measurements of signals received by the at least one UE from the serving base station and a neighbor base station, wherein the at least one notification includes a geometry threshold value for determining geometry of the at least one UE with respect to the neighbor base station; and

determining, based on at least one report that includes an indication of a geometry of at least one UE with respect to the neighbor base station, whether to generate a cell selection offset parameter for extending a range of the neighbor base station.

2. The method of claim 1, further comprising sending, by the serving base station, the cell selection offset.

3. The method of claim 2, wherein the serving base station sends the cell selection offset as at least one message according to either an X2 application protocol or an S1 application protocol.

4. The method of claim 1, wherein the serving base station transmits at least one notification by transmitting a message on a broadcast control channel.

5. The method of claim 1, wherein the measurements include reference signal received powers of signals received by the at least one UE from the serving base station and the neighbor base station.

6. The method of claim 1, wherein whether to generate the cell selection offset parameter is determined based on a plurality of reports.

7. The method of claim 6, wherein whether to generate the cell selection offset parameter is determined based on a report that a number of UEs that do not have interference cancellation capability is greater than the geometry threshold value and are located within an extended range area of the neighbor base station when the selection offset parameter is to be applied to all of the number of UEs.

8. A method of operating a user equipment (UE) in a communication network that includes a serving base station, at least one neighbor base station, and the UE located within communication range of the serving base station and the at least one neighbor base station, the method comprising:

receiving, by the UE, a notification to inform the serving base station of an interference cancellation capability of the UE and of measurements of signals received by the UE from the serving base station and a neighbor base station, wherein the notification includes a geometry threshold value for determining the UE'"'"'s geometry with respect to the neighbor base station; and

determining, based on the geometry threshold value, a geometry value that indicates the UE'"'"'s geometry with respect to the neighbor base station.

9. The method of claim 8, wherein the UE determines the geometry value according to:

10. The method of claim 8, further comprising transmitting an indication of the interference cancellation capability of the UE and the geometry value on a dedicated control channel.

11. The method of claim 10, wherein the indication and the geometry value are transmitted if the geometry value is less than the geometry threshold value.

12. An arrangement in a serving base station for a communication network that includes the serving base station, at least one neighbor base station, and at least one user equipment (UE) located within communication range of the serving base station and the at least one neighbor base station, the arrangement comprising:

a transmitter configured for sending at least one notification to inform the serving base station of interference cancellation capability of at least one UE and of measurements of signals received by the at least one UE from the serving base station and a neighbor base station, wherein the at least one notification includes a geometry threshold value for determining geometry of the at least one UE with respect to the neighbor base station; and

an electronic processor circuit configured for determining, based on at least one report that includes an indication of geometry of the at least one UE with respect to the neighbor base station, whether to generate a cell selection offset parameter for extending a range of the neighbor base station.

13. The arrangement of claim 12, further comprising an interface configured for sending the cell selection offset parameter.

14. The arrangement of claim 13, wherein the interface is configured for sending the cell selection offset parameter as at least one message according to an X2 application protocol or an S1 application protocol.

15. The arrangement of claim 13, wherein the interface is configured for sending a receiver type of a UE to be handed over to the neighbor base station as at least one message according to an X2 application protocol or an S1 application protocol.

16. The arrangement of claim 12, wherein the transmitter is configured to send at least one notification as at least one message on a broadcast control channel or on a dedicated signaling channel.

17. The arrangement of claim 12, wherein the measurements include reference signal received powers of signals received by the at least one UE from the serving base station and the neighbor base station.

18. The arrangement of claim 12, wherein the electronic processor circuit determines to generate the cell selection offset parameter based on a plurality of reports.

19. The arrangement of claim 18, wherein the electronic processor circuit determines to generate the cell selection offset parameter based on a report that a number of UEs that do not have interference cancellation capability is greater than the geometry threshold value and are located within an extended range area of the neighbor base station when the selection offset parameter is to be applied to all of the number of UEs.

20. An arrangement in a user equipment (UE) for a communication network that includes a serving base station, at least one neighbor base station, and the UE located within communication range of the serving base station and the at least one neighbor base station, the arrangement comprising:

a receiver configured for receiving a notification to inform the serving base station of an interference cancellation capability of the UE and of measurements of signals received by the UE from the serving base station and a neighbor base station, wherein the notification includes a geometry threshold value for determining the UE'"'"'s geometry with respect to the neighbor base station; and

an electronic processor circuit configured for determining, based on the geometry threshold value, a geometry value that indicates the UE'"'"'s geometry with respect to the neighbor base station.

21. The arrangement of claim 20, wherein the electronic processor circuit is configured for determining the geometry value according to:

22. The arrangement of claim 21, further comprising a transmitter configured for transmitting an indication of the interference cancellation capability of the UE and the geometry value on a dedicated control channel.

23. The arrangement of claim 22, wherein the transmitter is configured for transmitting the indication and the geometry value if the geometry value is less than the geometry threshold value.