APPARATUS AND METHOD FOR SUPPORTING RELAY SERVICE IN MULTIHOP RELAY WIRELESS COMMUNICATION SYSTEM

• US 20080095038A1
• Filed: 10/19/2007
• Published: 04/24/2008
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Limited (Samsung Electronics Co. Ltd.)
• Inventors: Cho, Jae-Weon, Chang, Young-Bin, Lee, Sung-Jin, Son, Yeong-Moon, Oh, Chang-Yoon, Kang, Hyun-Jeong, Lim, Hyoung-Kyu
• Granted Patent: US 8,218,461 B2
• Time in Patent Office: Days
• US Class Current: 370/208
• CPC Class Codes: H04B 7/15542 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 Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 84/047 using dedicated repeater stations
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

Apparatus and method for supporting a relay service in a multihop relay wireless communication system are provided. The method includes setting Tx/Rx mode switch region information of a Relay Station (RS). A signal is sent to a Mobile Station (MS) traveling in a service coverage during a first interval of a DownLink (DL) subframe according to resource allocation information. The mode switch region information and a signal are sent over a second interval of the DL subframe. Accordingly, the RS can communicate with a Base Station (BS) with accurate synchronization.

Claims

1. An upper node operation method in a wireless communication system using a relay scheme, the method comprising the steps of:

confirming Transmit (Tx) and Receive (Rx) operation switch information of a lower Relay Station (RS); and

sending a control message for the Tx/Rx operation switch to the lower RS.

2. The upper node operation method of claim 1, wherein the upper node is a Base Station (BS) or an upper RS.

3. The upper node operation method of claim 1, wherein the Tx/Rx operation switch information comprises at least one of time information required when the lower RS changes from a Tx mode to a Rx mode, and time information required when the lower RS changes from the Rx mode to the Tx mode.

4. The upper node operation method of claim 1, wherein the Tx/Rx operation switch information of the lower RS is confirmed using at least one of a method for receiving Tx/Rx switch information required by the lower RS in the process of a capability negotiation with the lower RS, and a method for determining the Tx/Rx operation switch information of the lower RS by taking into account maximum values of Tx/Rx operation switch times of the lower RS.

5. The upper node operation method of claim 4, wherein the maximum values of the Tx/Rx operation switch times of the lower RSs are determined by system information or at the upper node.

6. The upper node operation method of claim 1, wherein the control message comprises at least one of a confirm message for the Tx/Rx operation switch information requested by the lower RS, values determined by considering the Tx/Rx operation switch information requested by the lower RS, and overheads according to the Tx/Rx operation switch information of the lower RS.

7. The upper node operation method of claim 6, wherein the confirm message for the Tx/Rx operation switch information requested by the lower RS comprises at least one of identical information as the Tx/Rx operation switch information requested by the lower RS and an acknowledge message for the Tx/Rx operation switch information requested by the lower RS.

8. The upper node operation method of claim 6, wherein an overhead for changing from the Tx mode to the Rx mode of the overheads according to the Tx/Rx operation switch of the lower RS is calculated based on:

R-TTG=┌

OFDMsymbolunit(RSTTG−

RTD/2)┐

where R-TTG denotes the overhead according to the operation switch of the RS in a subframe, RSTTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a DownLink Delay (DLD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one Orthogonal Frequency Division Multiple (OFDM) symbol length.

9. The upper node operation method of claim 6, wherein an overhead for changing from the Rx mode to the Tx mode of the overheads according to the Tx/Rx operation switch of the lower RS is calculated based on:

R-RTG=┌

OFDMsymbolunit(RSRTG+RTD/2)┐

where R-RTG denotes the overhead according to the operation switch of the RS in a subframe, RSRTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a UpLink Delay (ULD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one OFDM symbol length.

10. A Relay Station (RS) operation method in a wireless communication system using a relay scheme, the method comprising the steps of:

confirming signal delay times with an upper node;

exchanging Transmit (Tx) and Receive (Rx) operation switch time information with the upper node;

calculating overheads according to the Tx/Rx operation switch using the Tx/Rx operation switch time information and the signal delay times; and

communicating in accordance with the overheads.

11. The RS operation method of claim 10, wherein the signal delay times are acquired in the process of an initial access or a random access to the upper node.

12. The RS operation method of claim 10, wherein exchanging the Tx/Rx operation switch time information comprises:

determining Tx/Rx operation switch times; and

sending the determined Tx/Rx operation switch times to the upper node in a process of a capability negotiation with the upper node.

13. The RS operation method of claim 12, wherein exchanging the Tx/Rx operation switch time information further comprises:

after sending the determined Tx/Rx operation switch times to the upper node, receiving an acknowledge message for the sent Tx/Rx operation switch times from the upper node or Tx/Rx operation switch time information determined at the upper node.

14. The RS operation method of claim 12, wherein the determined Tx/Rx operation switch times are smaller than or equal to maximum values of the Tx/Rx operation switch times.

15. The RS operation method of claim 14, wherein the maximum values of the Tx/Rx operation switch time are set by system common information or provided from the upper node.

16. The RS operation method of claim 10, wherein an overhead for changing from a Tx mode to a Rx mode of overheads according to the Tx/Rx operation switch is calculated based on:

R-RTG=┌

OFDMsymbolunit(RSTTG−

RTD/2)┐

where R-TTG denotes the overhead according to the operation switch of the RS in a subframe, RSTTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a DownLink Delay (DLD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one OFDM symbol length.

17. The RS operation method of claim 10, wherein an overhead for changing from a Rx mode to a Tx mode of overheads according to the Tx/Rx operation switch is calculated based on:

R-RTG=┌

OFDMsymbolunit(RSRTG+RTD/2)┐

where R-RTG denotes the overhead according to the operation switch of the RS in a subframe, RSRTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a UpLink Delay (ULD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one OFDM symbol length.

18. The RS operation method of claim 10, wherein the upper node is a Base Station (BS) or an upper RS.

19. A Relay Station (RS) in a wireless communication system using a relay scheme, the RS comprising:

a timing controller for issuing a timing signal for a Transmit (Tx) and Receive (Rx) operation switch;

a transmitter for generating a frame according to a frame construction and sending the frame via an antenna when the RS enters a Tx mode according to the timing signal; and

a receiver for detecting and confirming a corresponding subframe from the frame received on the antenna when the RS enters a Rx mode according to the timing signal.

20. The RS of claim 19, wherein the timing controller calculates overheads for Tx/Rx operation switch times determined in a process of a capability negotiation with an upper node and transmitted to the upper node or calculates Tx/Rx operation switch times determined by negotiating with the upper node, and issues a timing signal according to the overheads.

21. The RS of claim 20, wherein the timing controller calculates an overhead for changing from a Tx mode to a Rx mode of the overheads for Tx/Rx operation switch times based on:

R-TTG=┌

OFDMsymbolunit(RSTTG−

RTD/2)┐

where R-TTG denotes the overhead according to the operation switch of the RS in the subframe, RSTTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a DownLink Delay (DLD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one OFDM symbol length.

22. The RS of claim 20, wherein the timing controller calculates an overhead for changing from a Rx mode to a Tx mode of the overheads for the Tx/Rx operation switch based on:

R-RTG=┌

OFDMsymbolunit(RSRTG+RTD/2)┐

where R-RTG denotes the overhead according to the operation switch of the RS in the subframe, RSRTG denotes a Tx/Rx operation switch region of the RS, RTD/2 denotes a UpLink Delay (ULD) time of a signal, and OFDMsymbolunit(x) denotes a function which divides the value x by one OFDM symbol length.

23. The RS of claim 19, wherein the upper node is a Base Station (BS) or an upper RS.