METHOD AND APPARATUS FOR INTER-CELL LOAD DISTRIBUTION AND INTERFERENCE MITIGATION IN WIRELESS COMMUNICATION SYSTEM

• US 20160353347A1
• Filed: 01/28/2015
• Published: 12/01/2016
• Est. Priority Date: 01/28/2014
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: JEON, Namryul, JUN, Byungwook, KIM, Eunyong, MAENG, Seungjoo, HAN, Seunghee
• Granted Patent: US 10,999,774 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04W 16/04 Traffic adaptive resource partitioning
• CPC Class Codes: H04W 16/06 Hybrid resource partitioning, e.g. channel borrowing
• CPC Class Codes: H04W 16/08 Load shedding arrangements
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 28/0236 radio quality, e.g. interference, losses or delay
• CPC Class Codes: H04W 28/0864 of different hierarchy levels, e.g. Master Evolved Node B [MeNB] or Secondary Evolved node B [SeNB]
• CPC Class Codes: H04W 28/0958 based on metrics or performance parameters
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 36/20 for optimising the interference level
• CPC Class Codes: H04W 68/005 Transmission of information for alerting of incoming communication
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

The present invention relates to a method and an apparatus for an inter-cell load distribution and interference mitigation in a wireless communication system, and the inter-cell load distribution method by a first base station in a heterogeneous network wireless communication system including the first base station and a second base station for solving the above-described problem, comprises the steps of: setting a reserved area for the second base station so as to distribute an inter-cell load; and managing a terminal according to the reserved area.

Claims

1. An inter-cell load balancing method of a first base station in a wireless communication system of a heterogeneous network (HetNet) including the first base station and a second base station comprising:

setting up a reserved region for the second base station in order to balance inter-cell load; and

controlling the load balancing between base stations, according to the reserved region.

2. The method of claim 1, wherein the controlling of the load balancing comprises:

dividing a terminal, whose serving base station is the first base station, into a first base station reserved region terminal and a first base station non-reserved region terminal; and

managing the terminals.

3. The method of claim 2, further comprising:

determining whether the load balancing needs to be performed at a preset period; and

handing over a terminal to the second base station, when the load balancing needs to be performed.

4. The method of claim 3, wherein the determining of whether the load balancing needs to be performed comprises:

determining whether the load balancing needs to be performed based on at least one of the following;

a condition as to whether an inter-cell interference control function is activated, a condition as to whether an inter-cell interference control partner cell exists,

an almost blank subframe (ABS) rate currently in use, and

a condition whether a macro cell reserved region terminal exists.

5. The method of claim 4, wherein after the determination, the method further comprises:

selecting one or more terminals for the load balancing;

requesting a measurement report from the selected terminal; and

receiving a measurement report from the selected terminal, in response to the request.

6. The method of claim 5, wherein the selecting of one or more terminals comprises:

selecting a terminal, located in a reserved region for the second base station whose load is less than or equal to a predefined threshold, as a terminal for the load balancing.

7. The method of claim 5, wherein the handing over of a terminal to the second base station comprises:

determining a terminal, which has the highest reference signal received power (RSRP) from the second base station, as a terminal which needs to be handed over.

8. The method of claim 1,

wherein the reserved region comprises first and second reserved regions,

wherein the first reserved region is a region to manage terminals which do not support a neighbor cell interference removal function, and

wherein the second reserved region is a region to manage terminals which support a neighbor cell interference removal function.

9. The method of claim 1, wherein the reserved region is an expanded cell region of the second base station from which a preset cell region of the second base station is excluded.

10. The method of claim 1,

wherein, when the first base station is a macro base station, the second base station is a small base station, or

wherein, when the first base station is a small base station, the second base station is a macro base station.

11. The method of claim 1, further comprising:

transmitting, to a terminal whose serving base station is the first base station, a measurement report setup message which is set to perform the measurement report by a terminal that moves into or out of the reserved region.

12. The method of claim 1, further comprising:

receiving a measurement report from a terminal that moves into the reserved region; and

managing the terminal that moves into the reserved region as a first base station reserved region terminal.

13. The method of claim 1, further comprising:

receiving a measurement report from a terminal that moves out of the reserved region; and

managing the terminal that moves out of the reserved region as a first base station non-reserved region terminal.

14. A first base station for balancing load between cells in a wireless communication system of a heterogeneous network (HetNet) including the first base station and a second base station comprising:

a transceiver configured to transmit/receive signals to/from a terminal or the second base station; and

a controller configured to;

set up a reserved region for the second base station in order to balance inter-cell load; and

control the load balancing between base stations, according to the reserved region.

15. The base station of claim 14,

wherein the controller is further configured to:

divide a terminal, whose serving base station is the first base station, into a first base station reserved region terminal and a first base station non-reserved region terminal, and

manage the terminals,

wherein the controller is further configured to;

determine whether the load balancing needs to be performed at a preset period, and

hand over a terminal to the second base station when the load balancing needs to be performed, and

wherein the controller is further configured to determine whether the load balancing needs to be performed based on at least one of the following;

a condition as to whether an inter-cell interference control function is activated,

a condition as to whether an inter-cell interference control partner cell exists,

an almost blank subframe (ABS) rate currently in use, and

a condition whether a macro cell reserved region terminal exists.

16-26. -26. (canceled)

27. A measurement reporting method of a terminal in a wireless communication system of a heterogeneous network (HetNet) including first and second base stations comprising:

receiving a measurement report setup message from the first base station;

detecting whether the terminal moves into or out of a reserved region of the second base station; and

transmitting a measurement report to the first base station according to the settings of the measurement report setup message.

28. The method of claim 27, wherein the reserved region is a region set to balance inter-cell load.

29. The method of claim 27,

wherein the reserved region comprises first and second reserved regions,

wherein the first reserved region is a region to manage terminals which do not support a neighbor cell interference removal functions, and

wherein the second reserved region is a region to manage terminals which support a neighbor cell interference removal function.

30. The method of claim 27, further comprising:

when receiving a handover message from the first base station, performing the handover to the second base station.

31. A terminal for performing the measurement report in a wireless communication system of a heterogeneous network (HetNet) including first and second base stations comprising:

a transceiver configured to transmit/receive signals to/from the base stations; and

a controller configured to;

receive a measurement report setup message from the first base station;

detecting whether the terminal moves into or out of a reserved region of the second base station, and

transmit a measurement report to the first base station according to the settings of the measurement report setup message.

32-34. -34. (canceled)