Method and network node in a wireless communication system

• US 9,037,179 B2
• Filed: 01/10/2012
• Issued: 05/19/2015
• Est. Priority Date: 06/17/2011
• Status: Expired due to Fees

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Johansson, Richard, Christensson, Anders, Lennartson, Benny, Riedel, Joakim
• Primary Examiner(s): PHU, SANH D
• Application Number:
  US13/392,624
• Publication Number:
  US 20120322488A1
• Time in Patent Office: 1,225 Days
• Field of Search: 455/513, 455/515, 455/511, 455/509, 455/524, 370/310, 370/315, 370/328, 370/329, 370/330
• US Class Current: 455/513
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 72/563 of the wireless resources

Abstract

Network node (120) and method in the network node (120) for allocating a radio resource in a first radio coverage area (115-1) when establishing a wireless communication with a mobile station (130-1), which radio resource is not assigned exclusively for the first radio coverage area (115-1) but may be shared between multiple radio coverage areas within a local radio environment.

Claims

1. A method in a network node for sharing radio resources among a plurality of radio units included in a local radio environment, each radio unit serving a respective radio coverage area and said method comprising:

performing a planning procedure that includes, for a first one of the radio units having a respective first one of the radio coverage areas, determining a ranking of the other radio units representing preferences for sharing radio resources with the other radio units; and

performing an allocation procedure in response to detection of a mobile station in the first radio coverage area, said allocation procedure including determining, based on said ranking of the other radio units, a shared radio resource to be allocated at the first radio unit for establishing a wireless communication with the mobile station, and wherein the shared radio resource is shared with one of the other radio units in the local radio environment.

2. The method according to claim 1, wherein determining the ranking of the other radio units includes:

estimating at least one of the mutual interference caused between the first radio unit and mobile stations situated in any of the other radio coverage areas in the local radio environment, and the mutual interference caused between the other radio units in the local radio environment and mobile stations situated in the first radio coverage area; and

ranking the other radio units according to the estimated mutual interference caused.

3. The method according to claim 2, wherein the estimation of mutual interference is based on at least one of:

statistical measurements made for a plurality of mobile stations situated in the radio coverage areas in the local radio environment;

geographical positions of the radio units; and

knowledge of signal propagation constraints of any of the radio units.

4. The method according to claim 1, wherein the allocation procedure comprises:

estimating at least one of;

the mutual interference caused between the mobile station situated in the first radio coverage area and one or more of the other radio units;

and the mutual interference caused between the first radio unit and other mobile stations situated in one or more of the other radio coverage areas, if such other mobile stations were to share the same shared radio resource as the one being allocated at the first radio unit; and

determining the shared radio resource to be allocated further based on the estimated mutual interference caused.

5. The method according to claim 1, further comprising:

determining whether a guard zone condition is met by determining at least one of;

whether the mobile station is situated within a guard zone of the first radio coverage area; and

whether other mobile stations are situated within a guard zone of the respective radio coverage areas; and

when the guard condition is met, disallowing the allocation of any shared radio resource for communication between the first radio unit and the mobile station.

6. The method according to claim 1, wherein the allocation of the shared radio resource is further based on considering the receiver capability of the mobile station.

7. The method according to claim 1, wherein the allocation procedure includes allocating a shared radio resource even when a unique radio resource is available, in order to save the unique radio resource for future potential use for connections with any mobile station that is disallowed to use the shared radio resource.

8. The method according to claim 1, wherein the allocation procedure is further based on evaluating measurement reports received from mobile stations or radio units situated in radio coverage areas within the local radio environment.

9. The method according to claim 1, wherein in determining the shared radio resource to be allocated, the allocation procedure includes:

estimating at least one of;

the mutual interference caused between the mobile station situated within the first radio coverage area and one or more of the other radio units; and

the mutual interference caused between the first radio unit and other mobile stations situated in one or more other ones of the radio coverage areas within the local radio environment; and

wherein said estimating is based on at least one of;

the locality of the mobile stations within the respective radio coverage areas; and

measurement reports received from mobile stations or radio units situated in the local radio environment.

10. The method according to claim 1, wherein the planning procedure includes re-configuring the selection of radio coverage areas to be included in the local radio environment, based on the number of released radio resources due to the amount of planned shared radio resources within the local radio environment, for increasing the number of radio coverage areas that are included in the local radio environment.

11. The method according to claim 10, wherein the planning procedure further comprises evaluating the re-configured local radio environment by comparison with other potential configurations of the local radio environment, for increasing the number of radio coverage areas included in the local radio environment.

12. The method according to claim 1, wherein the planning procedure further comprises assigning radio resources to each radio unit within the local radio environment to be used when establishing wireless communication with mobile stations situated in the radio coverage areas during the allocation procedure.

13. The method according to claim 1, further comprising allocating the shared radio resource to the first radio unit from a pool of radio resources that are available for use within the local radio environment.

14. A network node for sharing radio resources among a plurality of radio units included in a local radio environment, each radio unit serving a respective radio coverage area and said network node comprising processing circuitry configured to:

perform a planning procedure that includes, for a first one of the radio units having a respective first one of the radio coverage areas, determining a ranking of the other radio units representing preferences for sharing radio resources with the other radio units; and

perform an allocation procedure in response to detection of a mobile station in the first radio coverage area, said allocation procedure including determining, based on said ranking of the other radio units, a shared radio resource to be allocated at the first radio unit for establishing a wireless communication with the mobile station, and wherein the shared radio resource is shared with one of the other radio units in the local radio environment.

15. The network node according to claim 14, wherein the processing circuitry is configured to rank the radio units in order of preference based on estimates of the mutual interference caused between the first radio unit and mobile stations situated in one or more of the other radio coverage areas in the local radio environment or the mutual interference caused between the other radio units in the local radio environment and mobile stations situated in the first radio coverage area.

16. The network node according to claim 15, wherein the processing circuitry is further configured to estimate the mutual interference based on at least one of:

statistical measurements made for a plurality of mobile stations situated in the radio coverage areas included in the local radio environment;

geographical positions of the radio units; and

knowledge about signal propagation constraints of any of the radio units.

17. The network node according to claim 14, wherein as part of determining the shared radio resource to be allocated, the processing circuitry is further configured to estimate at least one of:

the mutual interference caused between the mobile station situated within the first radio coverage area and one or more of the other radio; and

the mutual interference caused between the first radio unit and mobile stations situated in one or more of the other radio coverage areas, if such other mobile stations were to share the same shared radio resource as the one being allocated at the first radio unit.

18. The network node according to claim 14, wherein the processing circuitry is further configured to determine whether a guard zone condition is met by determining whether the mobile station is situated within a guard zone of the first radio coverage area or whether other mobile stations are situated within a guard zone of the respective radio coverage areas, and, if the guard zone condition is met, to disallow allocation of any shared radio resource for communication between the first radio unit and the mobile station.

19. The network node according to claim 14, wherein the processing circuitry is further configured to allocate the shared radio resource based on the receiver capability of the mobile station.

20. The network node according to claim 14, wherein the processing circuitry is further configured to allocate the shared radio resource to the first radio unit even when a unique radio resource is available, in order to save the unique radio resource for future potential use for connections with any mobile station that is disallowed to use the shared radio resource.

21. The network node according to claim 14, wherein the processing circuitry is further configured determine the shared radio resource to be allocated based on evaluating measurement reports received from mobile stations in one or more of the radio coverage areas or one or more of the other radio units.

22. The network node according to claim 21, wherein the processing circuitry is further configured to:

consider mutual interference when determining the shared radio resource to be allocated;

estimate the mutual interference as at least one of;

the mutual interference caused between the mobile station situated within the first radio coverage area and radio units within the local radio environment; and

the mutual interference caused between the first radio unit and mobile stations situated in other radio coverage areas within the local radio environment; and

base the estimation of the mutual interference on at least one of;

the locality of the mobile stations within the respective radio coverage areas; and

measurement reports received from mobile stations or radio units situated in the local radio environment.

23. The network node according to claim 14, wherein the processing circuitry is further configured, as part of said planning procedure, to re-configure the selection of radio coverage areas to be included in the local radio environment, based on the number of released radio resources due to the amount of planned shared radio resources within the local radio environment, for increasing the number of radio coverage areas comprised within the local radio environment.

24. The network node according to claim 23, wherein the processing circuitry is further configured, as part of said planning procedure, to evaluate the re-configured local radio environment by comparison with other potential configurations of the local radio environment, for increasing the number of radio coverage areas included within the local radio environment.

25. The network node according to claim 14, wherein the processing circuitry is further configured, as part of said planning procedure, to assign radio resources to each radio unit within the local radio environment to be used when establishing wireless communication with mobile stations situated in the radio coverage areas during the allocation procedure.

26. The network node according to claim 14, wherein the processing circuitry is further configured to allocate the shared radio resource to be allocated to the first radio unit from a pool of radio resources that are available for use within the local radio environment.

27. The network node according to claim 14, wherein the network node comprises a base station controller.

28. The network node according to claim 14, wherein the network node comprises a base transceiver station.