Method and device for avoiding inter-cell interference in a wireless access system

Patent metadata

Field	Value
Publication number	US-9426811-B2
Application number	US-201113984772-A
Country	US
Kind code	B2
Filing date	Oct 6, 2011
Priority date	Feb 9, 2011
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

According to the present invention, a method for a relay node (RN) to reallocate a resource in order to avoid inter-cell interference (ICI) in a wireless access system includes: overhearing a control channel including downlink or uplink resource allocation information transmitted by a plurality of base stations to terminals in the coverage area of each base station; sharing the RN by means of the plurality of base stations; confirming that there is a resource area in which conflicts are occurring by comparing resource areas allocated to terminals in the coverage area of the RN through the control channel; and, if it is determined, on the basis of the confirmation result, that there is a resource area in which conflicts are occurring, reallocating a resource to the resource area in which conflicts are occurring.

First claim

The invention claimed is:

1. A method for reallocating resources in order to avoid Inter-Cell Interference (ICI) in a wireless access system communicating by using a radio frame including a first time zone and a second time zone, the method performed by a Relay Node (RN) and comprising:
in the first time zone, overhearing a control channel comprising downlink or uplink resource allocation information transmitted from each of a plurality of eNBs to user equipments (UEs) within a coverage of each of the plurality of eNBs, wherein the plurality of eNBs shares the RN;
in the second time zone, checking whether or not a colliding resource region is present by comparing resource regions, allocated to UEs within a coverage of the RN, with each other through the control channel;
in the second time zone, if the colliding resource region is present, transmitting, to the plurality of eNBs, information on first identifications of the UEs within the coverage of the RN and second identifications of UEs using the colliding resource region;
in the second time zone, if the colliding resource region is present, exchanging the colliding resource region with resource regions allocated to UEs outside the coverage of the RN by using the first identifications and the second identifications, wherein the exchanged resource regions do not include the resource regions allocated to the UEs within the coverage of the RN; and
in the second time zone, transmitting data to the UEs through the exchanged resource region,
wherein the first time zone comprises downlink and uplink regions, and
wherein the second time zone comprises downlink and uplink regions.

2. The method of claim 1 , wherein the exchanging the colliding resource regions includes:
comparing a Signal-to-Interference plus Noise Ratio (SINR) value of the colliding resource region with an SINR value of each of the resource regions allocated to the UEs outside the coverage of the RN; and
determining a resource region, having a smallest SINR value difference as a result of the comparison, as the resource region to be exchanged.

3. The method of claim 1 , wherein the plurality of eNBs performs a dynamic resource allocation based on Full Frequency Reuse (FFR).

4. The method of claim 1 , wherein:
the plurality of eNBs comprises 3 eNBs, and
the RN is a Shared Relay Node (SRN) shared by the 3 eNBs.

5. The method of claim 1 , wherein the performing the resource reallocation includes:
classifying all the UEs within the coverage of the RN into UEs corresponding to each of the eNBs; and
transmitting ratio information about the classified UEs to each of the eNBs.

6. The method of claim 5 , wherein the ratio information about the classified UEs is transmitted to each of the eNBs through an X2 interface.

7. The method of claim 1 , wherein the control channel is a Physical Downlink Control Channel (PDCCH) or a Physical Uplink Control Channel (PUCCH).

8. A Relay Node (RN) for reallocating resources in order to avoid Inter-Cell Interference (ICI) in a wireless access system communicating by using a radio frame including a first time zone and a second time zone, the RN comprising:
a radio frequency (RF) communication unit for transmitting and receiving radio signals; and
a processor, operatively coupled with the RF communication unit, configured to:
in the first time zone, overhear a control channel comprising downlink or uplink resource allocation information transmitted from each of a plurality of eNBs to user equipments (UEs) within a coverage of each of the plurality of eNBs, wherein the plurality of eNBs shares the RN,
in the second time zone, check whether or not a colliding resource region is present by comparing resource regions, allocated to UEs within a coverage of the RN, with each other through the control channel,
in the second time zone, if the colliding resource region is present, transmit, to the plurality of eNBs, information on first identifications of the UEs within the coverage of the RN and second identifications of UEs using the colliding resource region,
in the second time zone, if the colliding resource region is present, exchange the colliding resource region with resource regions allocated to UEs outside the coverage of the RN by using the first identifications and the second identifications, wherein the exchanged resource regions do not include the resource regions allocated to the UEs within the coverage of the RN, and
in the second time zone, transmit data to the UEs through the exchanged resource region,
wherein the first time zone comprises downlink and uplink regions, and
wherein the second time zone comprises downlink and uplink regions.

9. The RN of claim 8 , wherein the processor is configured to:
compare a Signal-to-Interference plus Noise Ratio (SINR) value of the colliding resource region with an SINR value of each of the resource regions allocated to the UEs outside the coverage of the RN and determines a resource region, having a smallest SINR value difference as a result of the comparison, as the resource region to be exchanged.

10. The RN of claim 8 , wherein the plurality of eNBs performs a dynamic resource allocation based on Full Frequency Reuse (FFR).

11. The RN of claim 8 , wherein the processor is configured to:
classify all the UEs within the coverage of the RN into UEs corresponding to each of the eNBs and transmit ratio information about the classified UEs to each of the eNBs.

Assignees

• Kim Hakseong
• Yang Mochan
• Yoo Sungcheol
• Shin Ohsoon
• Shin Yoan
• Lg Electronics Inc
• Sungkyunkwan Univ Found For Corp

Inventors

• Kim Hakseong
• Yang Mochan
• Yoo Sungcheol
• Shin Ohsoon
• Shin Yoan

Classifications

• H04W72/541 Primary

  using the level of interference · CPC title

• H04W16/10

  Dynamic resource partitioning · CPC title

• H04B7/15542

  Selecting at relay station its transmit and receive resources (selection of wireless resources by user or terminal H04W72/02; arrangements affording multiple use of the transmission path by two-dimensional division of the resources H04L5/0003, or by allocating sub-channels H04L5/003) · CPC title

• H04J11/005

  of intercell interference · CPC title

• H04W72/082 Primary

  Electricity · mapped topic