Method and apparatus for scheduling in cellular system using cable relay station

• US 8,238,299 B2
• Filed: 11/06/2008
• Issued: 08/07/2012
• Est. Priority Date: 11/06/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd., Sogang University Research Foundation
• Original Assignee: Samsung Electronics Co. Ltd., Sogang University Industry-University Cooperation Foundation
• Inventors: Lee, Jae-Hoon, Hwang, Seong-Taek, Sung, Won-Jin, Lee, Byoung-Seok, Sung, Ki-Suk, Shong, In-Hong, Choe, Jin-Woo
• Primary Examiner(s): Mills, Donald
• Assistant Examiner(s): Baron, Henry
• Application Number:
  US12/291,147
• Publication Number:
  US 20090135778A1
• Time in Patent Office: 1,370 Days
• Field of Search: 370/329, 370/311, 370/328, 455/454.1, 455/434
• US Class Current: 370/329
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A method for scheduling in a cellular system using a relay station (RS) through an inter-antenna cooperative transmission technology based on pre-cooperation information according to each channel in a cellular system using a cable RS in order to increase the throughput of the entire system. The steps include classifying all mobile stations (MSs) in a corresponding cell based into Cooperative Transmission (CT) MSs for cooperative transmission and Single Transmission (ST) MSs for to each channel; mapping channel-by-channel channel capacities of the CT MSs and ST MSs classified according to each channel, selecting a channel with a highest priority, and receiving a request message from a corresponding MS according to whether the capacity of the selected channel satisfies preset CT criteria and selecting an MS having a metric value of a highest priority according to a corresponding scheduling algorithm, from among multiple requesting MSs.

Claims

1. A method for scheduling in a cellular system using a relay station (RS), the method comprising the steps of:

classifying each of a plurality mobile stations (MSs) in a corresponding cell based on a base station (BS) into one of a Cooperative Transmission (CT) MSs for cooperative transmission and a Single Transmission (ST) MSs for single transmission according to each channel by signal-to-interference-plus-noise ratio (SINR) values of the MSs;

mapping the CT MSs and ST MSs classified according to each channel to a channel capacity of each channel, which has been allocated to each RS, selecting a channel with a largest channel capacity, comparing the channel capacity of the selected channel with preset CT criteria, and transmitting, by a corresponding MS, a single request message or multiple request messages to the RS through a corresponding channel according to a result of the comparison;

selecting an MS having a metric value of a highest priority according to a corresponding scheduling algorithm from among multiple MSs which have transmitted the request message(s), and transmitting a grant message to the selected MS; and

accepting a channel of a corresponding scheduler which has transmitted the grant message.

2. The method as claimed in claim 1, wherein the selecting channel step comprises selecting at least two channels having relatively largest channel capacities among the channels in an ST mode.

3. The method as claimed in claim 1, wherein, the step of classifying MSs into the CT MSs and the ST MSs comprises:

calculating a transmission capacity by using a particular SINR value from the SINR values of the MSs received from each MS according to each channel; and

applying the calculated transmission capacity of each MS to the following equations,

4. The method as claimed in claim 1, wherein the corresponding scheduling algorithm includes at least one among a proportional fair (PF) scheduler, a Modified Largest Weighted Delay First (M-LWDF) scheduler, and a MAX SINR scheduler.

5. The method as claimed in claim 1, wherein, when an MS “

k”

performs a single transmission (ST) through an antenna “

s”

on a subchannel “

n,”

a particular SINR value is expressed by

6. The method as claimed in claim 4, further comprising, when the corresponding scheduling algorithm is the proportional fair (PF) scheduling algorithm, the steps of:

(i) collecting channel state information (CSI) from a plurality of MS having data to transmit in a cell;

(ii) determining an available maximum data rate of each MS in a form of “

r_k[τ

], k=1, . . . , N”

from the collected CSI;

(iii) calculating a ratio

7. The method as claimed in claim 1, wherein, in the step of accepting the channel of the corresponding scheduler that has transmitted the grant message, each ST MS accepts a channel of a scheduler which has transmitted a grant message, and each CT MS accepts all channels of one or more schedulers which have transmitted grant messages.

8. An apparatus for scheduling in a cellular system using a cable relay station, the apparatus comprising:

an input unit for receiving signal-to-interference-plus-noise ratio (SINR) values from a plurality of mobile stations (MSs) according to each channel;

a determination unit for calculating transmission capacities of the plurality of MSs by using the SINR values of the MSs according to each channel, and applying the transmission capacities to predetermined equations;

9. The apparatus according to claim 8, wherein the determination unit selecting includes selecting at least two channels having relatively largest channel capacities among the channels in an ST mode.

10. The method as claimed in claim 8, wherein, the determination unit classifies the MSs into one of the CT MSs and the ST MSs by calculating a transmission capacity using a particular SINR value from the SINR values of the MSs received from each MS according to each channel.