System and Method for Grouping and Selecting Transmission Points

• US 20140003268A1
• Filed: 07/01/2013
• Published: 01/02/2014
• Est. Priority Date: 06/29/2012
• Status: Active Application

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Zarifi, Keyvan, Baligh, Mohammadhadi, Callard, Aaron, Ma, Jianglei, Salem, Mohamed Adel, Hawryluck, Mark Andrew
• Granted Patent: US 10,285,186 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 72/121 for groups of terminals or users

Abstract

A method for operating a centralized controller in a communications network with a plurality of transmission points includes generating a plurality of overlays for the communications network in accordance with first mutual intercell interference levels for transmission point pairs in the communications network, wherein each overlay of the plurality of overlays comprises virtual transmission points, and selecting a first overlay of the plurality of overlays in accordance with a merit measure derived from first user equipments (UEs) operating in the communications network tentatively scheduled to each overlay of the plurality of overlays. The method also includes scheduling a first subset of the first UEs operating in the communications network during a first resource unit in accordance with the selected first overlay.

Claims

1. A method for operating a centralized controller in a communications network with a plurality of transmission points, the method comprising:

generating, by the centralized controller, a plurality of overlays for the communications network in accordance with first mutual intercell interference levels for transmission point pairs in the communications network, wherein each overlay of the plurality of overlays comprises virtual transmission points;

selecting, by the centralized controller, a first overlay of the plurality of overlays in accordance with a merit measure derived from first user equipments (UEs) operating in the communications network tentatively scheduled to each overlay of the plurality of overlays; and

scheduling, by the centralized controller, a first subset of the first UEs operating in the communications network during a first resource unit in accordance with the selected first overlay.

2. The method of claim 1, wherein generating the plurality of overlays comprises:

deriving the first mutual intercell interference levels for the transmission point pairs from UE link weights, the UE link weights determined from at least one of long term measures reported by second UEs operating in the communications network and associated with the transmission point pairs, and short term measures reported by the second UEs operating in the communications network and associated with the transmission point pairs;

partitioning the communications network into a second overlay comprising a second plurality of virtual transmission points in accordance with the first mutual intercell interference levels for the transmission point pairs;

adjusting the UE link weights that exceed a weight threshold;

deriving second mutual intercell interference levels for the transmission point pairs from the adjusted UE link weights; and

partitioning the communications network into a third overlay comprising a third plurality of virtual transmission points in accordance with the second mutual intercell interference levels for the transmission point pairs.

3. The method of claim 2, wherein adjusting the UE link weights comprises reducing the UE link weights.

4. The method of claim 2, further comprising partitioning the communications network into the second overlay in accordance with a maximum number of transmission points per virtual transmission point.

5. The method of claim 1, wherein the first mutual intercell interference levels comprise transmission point to transmission point coordinated multiple point (CoMP) gain.

6. The method of claim 1, wherein selecting the first overlay of the plurality of overlays comprises:

for each fourth overlay in the plurality of overlays;

generating the merit measure for a second subset of the first UEs operating in the communications network and tentatively scheduled in accordance with the fourth overlay; and

selecting a fifth overlay associated with a largest merit measure of the merit measures as the first overlay.

7. The method of claim 6, wherein generating the merit measure comprises:

tentatively scheduling the second subset of the first UEs operating in the communications network to communicate during the first resource unit, the tentatively scheduling performed in accordance with the fourth overlay; and

determining the merit measure for the tentatively scheduled second subset of the first UEs operating in the communications network.

8. The method of claim 7, wherein the merit measure comprises one of a sum proportional fairness for the tentatively scheduled second subset of the first UEs operating in the communications network, data rate for the tentatively scheduled second subset of the first UEs operating in the communications network, a queue length for the tentatively scheduled second subset of the first UEs operating in the communications network, and a wait time for the tentatively scheduled second subset of the first UEs operating in the communications network.

9. The method of claim 1, wherein a virtual transmission point is a coordinated multiple point.

10. A method for partitioning a communications network comprising a plurality of transmission points, the method comprising:

deriving, by a centralized controller, mutual intercell interference levels for transmission point pairs in the communications network from long term measures reported by user equipments operating in the communications network;

partitioning, by the centralized controller, the communications network into a plurality of clusters in accordance with the mutual intercell interference levels for the transmission point pairs and backhaul information for the communications network; and

storing, by the centralized controller, information about the plurality of clusters.

11. The method of claim 10, wherein deriving the mutual intercell interference levels comprises:

determining a mutual interference level for each transmission point pair in accordance with interference that a first transmission point in the transmission point pair causes to an impacted user equipment associated with a second transmission point in the transmission point pair; and

generating the mutual intercell interference levels from the mutual interference levels.

12. The method of claim 10, wherein partitioning the communications network comprises grouping transmission points with mutual intercell interference levels exceeding an interference threshold and that are connected with a backhaul meeting a performance threshold into a virtual cluster in the plurality of clusters.

13. The method of claim 10, further comprising partitioning the communications network into the plurality of clusters in accordance with a maximum number of transmission points per cluster.

14. The method of claim 10, wherein the long term measure comprises a reference signal received power report.

15. A centralized controller comprising:

a processor configured to generate a plurality of overlays for a communications network in accordance with first mutual intercell interference levels for transmission point pairs in the communications network, wherein each overlay of the plurality of overlays comprises virtual transmission points, to select a first overlay of the plurality of overlays in accordance with a merit measure derived from first user equipments (UEs) operating in the communications network tentatively scheduled to each overlay of the plurality of overlays, and to schedule a first subset of the first UEs operating in the communications network during a first resource unit in accordance with the selected first overlay.

16. The centralized controller of claim 15, wherein the processor is configured to derive the first mutual intercell interference levels for the transmission point pairs from UE link weights, the UE link weights determined from at least one of long term measures reported by second UEs operating in the communications network and associated with the transmission point pairs, and short term measures reported by the second UEs operating in the communications network and associated with the transmission point pairs, to partition the communications network into a second overlay comprising a second plurality of virtual transmission points in accordance with the first mutual intercell interference levels for the transmission point pairs, to adjust the UE link weights that exceed a weight threshold, to derive second mutual intercell interference levels for the transmission point pairs from the adjusted UE link weights, and to partition the communications network into a third overlay comprising a third plurality of virtual transmission points in accordance with the second mutual intercell interference levels for the transmission point pairs.

17. The centralized controller of claim 16, wherein the processor is configured to partition the communications network into the second overlay in accordance with a maximum number of transmission points per virtual transmission point.

18. The centralized controller of claim 15, wherein the processor is configured to generate, for each fourth overlay in the plurality of overlays, the merit measure for a second subset of the first UEs operating in the communications network and tentatively scheduled in accordance with the fourth overlay, and to select a fifth overlay associated with a largest merit measure of the merit measures as the first overlay.

19. The centralized controller of claim 18, wherein the processor is configured to tentatively schedule the second subset of the first UEs operating in the communications network to communicate during the first resource unit, the tentatively scheduling performed in accordance with the fourth overlay, and to determine the merit measure for the tentatively scheduled second subset of the first UEs operating in the communications network.

20. A centralized controller comprising:

a processor configured to derive mutual intercell interference levels for transmission point pairs in a communications network from long term measures reported by user equipments operating in the communications network, to partition the communications network into a plurality of clusters in accordance with the mutual intercell interference levels for the transmission point pairs and backhaul information for the communications network, and to store information about the plurality of clusters.

21. The centralized controller of claim 20, wherein the processor is configured to determine a mutual interference level for each transmission point pair in accordance with interference that a first transmission point in the transmission point pair causes to an impacted user equipment associated with a second transmission point in the transmission point pair, and to generating the mutual intercell interference levels from the mutual interference levels.

22. The centralized controller of claim 20, wherein the processor is configured to group transmission points with mutual intercell interference levels exceeding an interference threshold and that are connected with a backhaul meeting a performance threshold into a cluster in the plurality of clusters.

23. The centralized controller of claim 20, wherein the processor is configured to partition the communications network into the plurality of clusters in accordance with a maximum number of transmission points per cluster.