SMALL CELL SYSTEM AND METHOD FOR ALLOCATING RESOURCE THEREOF

• US 20160360538A1
• Filed: 06/01/2016
• Published: 12/08/2016
• Est. Priority Date: 06/04/2015
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: YANG, Hyung Jong, SHIN, Mu Yong, JWA, Hye Kyung, NA, Jee Hyeon, KWON, Dong Seung
• Granted Patent: US 9,955,489 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

Provided is a method of allocating a resource in a small cell system. The method includes: selecting a temporary base station for each user terminal; measuring a signal-to-noise ratio (SNR) through a downlink pilot in a small cell base station; transmitting the signal-to-noise ratio measured for each user terminal to the temporary base station; receiving base station selection and resource allocation information from the small cell base station; and selecting the small cell base station to which most frequency resource block are allocated as a home base station.

Claims

1. A method of allocating a resource in a small cell system, the method comprising:

selecting a temporary base station for each user terminal;

measuring a signal-to-noise ratio (SNR) through a downlink pilot in a small cell base station;

transmitting the signal-to-noise ratio measured for each user terminal to the temporary base station;

receiving base station selection and resource allocation information from the small cell base station; and

selecting the small cell base station to which most frequency resource block are allocated as a home base station.

2. The method of claim 1, wherein measuring a signal-to-noise ratio comprises calculating an average SNR of k-th resource block in a channel between i-th small cell base station and j-th user terminal based on a parameter according to a performance of backhaul.

3. The method of claim 2, wherein measuring a signal-to-noise ratio comprises measuring a signal-to-noise ratio according to a following equation,

SNR_i,j^k=Σ

<sub>t−

1</sub>^TΣ

_f=k+1^k+FSNR_i,j(f,t) 

 

[Equation 1]

wherein, SNR_i,j (f, t) denotes a SNR values in t-th time slot of f-th subcarrier, N_UE denotes the number of user terminals in a cluster, N_RB denotes the number of small cell base stations in the cluster, F denotes a first parameter indicating the performance of backhaul, and T denotes a second parameter indicating the performance of backhaul.

4. The method of claim 3, wherein measuring a signal-to-noise ratio comprises setting the first parameter or the second parameter to a small value when a capacity of backhaul between small cells base stations is large, and setting to a large value when a capacity of backhaul between small cells base stations is small.

5. A method of allocating a resource in a small cell system, the method comprising:

performing a base station selection for each user and resource allocation that maximize a signal-to-noise-plus-interference ratio (SINR) by using a signal-to-noise ratio (SNR) feedbacked from a user terminal;

broadcasting base station selection for each user and resource allocation information; and

sharing a user terminal data necessary for all small cell base stations by using the resource allocation information and performing a downlink data transmission cooperatively.

6. The method of claim 5, wherein performing a base station selection for each user and a resource allocation comprises sharing the signal-to-noise ratio feedbacked from the user terminal and calculating an average SINR by using the signal-to-noise ratio, by the small cell base stations.

7. The method of claim 6, wherein performing a base station selection for each user and a resource allocation comprises calculating the average SINR according to a following equation 2,

8. The method of claim 5, wherein performing a base station selection for each user and a resource allocation comprises allocating a first user terminal to a first resource block in a first small cell base station which has a maximum SINR value among resource blocks, and removing slots of the first resource block of a second small cell base station of a second user terminal and a third user terminal, and the first resource block of a third small cell base station, when the first to a third resource blocks exist between the first to the third user terminals, and between the first to the third small cell base stations.

9. The method of claim 8, wherein performing a base station selection for each user and a resource allocation comprises allocating the second user terminal to a second resource block in the first small cell base station which has a maximum SINR value among non-allocated resource blocks, after allocating or removing the resource block, and removing slots of the second resource block of a second small cell base station of the first user terminal and the third user terminal, and the second resource block of the third small cell base station.

10. The method of claim 8, wherein performing a base station selection for each user and a resource allocation comprises allocating resources by a calculation method of linearly increasing as the number of user terminals increases.

11. The method of claim 5, wherein performing a downlink data transmission cooperatively comprises sharing a data to be allocated to each resource block with a corresponding small cell base station by a home base station selected by the user terminal.

12. A small cell system comprising:

a base station selection and resource allocation unit configured to perform a base station selection for each user and resource allocation by using a signal-to-noise ratio (SNR) feedbacked from a user terminal within a cluster;

a broadcast unit configured to broadcast base station selection and resource allocation information determined by the base station selection and resource allocation unit; and

a cooperative transmission unit configured to share user data information with all small cell base stations within the cluster by using the resource allocation information and perform a downlink data transmission cooperatively.

13. The small cell system of claim 12, wherein the base station selection and resource allocation unit performs the base station selection for each user and resource allocation that maximizes a signal-to-noise-plus-interference ratio (SINR) by using the signal-to-noise ratio.

14. The small cell system of claim 12, wherein the base station selection and resource allocation unit allocates a first user terminal to a first resource block in a first small cell base station which has a maximum SINR value among resource blocks, and removes slots of the first resource block of a second small cell base station of a second user terminal and a third user terminal, and the first resource block of a third small cell base station, when the first to a third resource blocks exist between the first to the third user terminals, and between the first to the third small cell base stations.

15. The small cell system of claim 14, wherein the base station selection and resource allocation unit performs the allocation or the removal of the resource block with respect to all resource blocks.

16. The small cell system of claim 12, wherein the base station selection and resource allocation unit shares the signal-to-noise ratio feedbacked from the user terminal with all small cell base stations within the cluster.