Method and system for assigning radio resources in cellular system using wired relay stations

• US 7,969,940 B2
• Filed: 09/10/2007
• Issued: 06/28/2011
• Est. Priority Date: 11/21/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd., University-Industry Foundation Yonsei University
• Original Assignee: Samsung Electronics Co. Ltd., Sogang University Industry-University Cooperation Foundation
• Inventors: Park, Jong-Hyun, Kim, Jong-Hyun, Sung, Won-Jin, Choe, Jin-Woo, Hwang, Seong-Taek, Kim, Byung-Jik
• Primary Examiner(s): Sam; Phirin
• Application Number:
  US11/900,333
• Publication Number:
  US 20080119194A1
• Time in Patent Office: 1,387 Days
• Field of Search: None
• US Class Current: 370/329
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A method of assigning radio resources in a cellular system using wired Relay Stations (RSs) includes: a Base Station (BS) gathering feed-back control information of all Mobile Stations (MSs) via the RSs in a cell of the BS; a first process, wherein the MSs are divided into two groups according to a channel state of each MS; a second process, wherein sub-channels are dynamically assigned to MSs belonging to a group, in which a channel state of each MS is good, of the two groups; and a third process, wherein sub-channels are dynamically assigned to MSs belonging to a group, in which a channel state of each MS is bad, of the two groups by considering a resource state per RS and a channel gain between sub-channels.

Claims

1. A method of assigning radio resources in a cellular system using wired Relay Stations (RSs), the method comprising:

a Base Station (BS) gathering feed-back control information of all Mobile Stations (MSs) via the RSs located in a cell of the BS;

dividing the MSs into two groups according to a channel state of each MS;

dynamically assigning sub-channels to the MSs belonging to one of the two groups, in which a channel state of each MS is above a predetermined quality;

dynamically assigning sub-channels the MSs belonging to one of the two groups, in which a channel state of each MS is below the predetermined quality, by considering a resource state per RS and signal levels of sub-channels to be assigned to each MS.

2. The method of claim 1, wherein the dividing the MSs into two groups comprises:

calculating the numbers of mean transmission bits per MS, which can be received from each RS using the entire sub-channels;

obtaining a RS index corresponding to the greatest value among the numbers of mean transmission bits;

comparing the number of mean transmission bits corresponding to the RS index to a pre-set threshold; and

grouping a relevant MS according to a result of the comparison.

3. The method of claim 1, wherein the assigning sub-channels to the MSs belonging to one of the two groups, in which the channel state of each MS is above the predetermined quality comprises:

selecting a sub-channel having the maximum number of transmission bits from among non-assigned sub-channels in order to assign a sub-channel to each MS; and

repeatedly assigning a sub-channel to the MS until a minimum data rate of the MS is satisfied.

4. The method of claim 1, wherein the assigning sub-channels the MSs belonging to one of the two groups, in which the channel state of each MS is below the predetermined quality comprises:

gathering channel information per RS for MSs belong to the channel state group below the predetermined quality; and

calculating a metric for RS selection for all MSs and all RSs of the channel state group.

5. The method of claim 4, wherein the metric is represented by the equation below;

selecting a pair of MS and RS (d_k,s) having the greatest selection metric as a result of the calculation;

selecting a sub-channel having the maximum number of transmission bits from among non-assigned sub-channels in order to assign a sub-channel to the selected MS;

repeatedly assigning a sub-channel until a minimum data rate of the MS is satisfied; and

repeatedly performing the above steps for all MSs belong to the channel state group below the predetermined quality,

6. The method of claim 1, further comprising if a non-assigned sub-channel exists even after the processes end, selecting a MS having the greatest number of transmission bits from among MSs for the non-assigned sub-channel and assigning the non-assigned sub-channel to the selected MS.

7. A system programmed to perform the method of claim 1.