APPARATUS AND METHOD FOR PERFORMING RANDOM ACCESS IN MULTI-CARRIER SYSTEM

• US 20110249641A1
• Filed: 04/08/2011
• Published: 10/13/2011
• Est. Priority Date: 04/09/2010
• Status: Abandoned Application

• Current Assignee: Pantech Corporation (Ideahub, Inc.)
• Original Assignee: Pantech Corporation (Ideahub, Inc.)
• Inventors: JUNG, Myung Cheul, KWON, Ki Bum
• Application Number:
  US13/083,037
• Publication Number:
  US 20110249641A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0858 collision detection

Abstract

A method for performing a random access in a multi-carrier system includes transmitting a random access preamble on an uplink component carrier to a base station, and receiving a random access response on a first downlink component carrier. The random access response includes information regarding a second downlink component carrier used to transmit a contention resolution message indicating that a random access collision with other mobile stations are resolved. A base station to perform the method includes a preamble reception unit to receive the random access preamble, a response generation unit to generate the random access response, and a response transmission unit to transmit the random access response. A mobile station to perform the method includes a preamble transmission unit, a response reception unit, a carrier configuration unit, and a message reception unit.

Claims

1. A method for performing a random access by a mobile station in a multi-carrier system, the method comprising:

transmitting a first random access preamble on a first uplink (UL) component carrier (CC) to a base station (BS); and

receiving a random access response (RAR) on a first downlink (DL) CC linked to the first UL CC,

wherein the RAR comprises information regarding a second DL CC, and the second DL CC is used to transmit a contention resolution (CR) message indicating that a random access collision with other mobile stations are resolved.

2. The method of claim 1, wherein the second DL CC is a primary CC (PCC) and the first DL CC is a secondary CC (SCC).

3. The method of claim 1, wherein the RAR comprises information regarding a random access suspension, and the information regarding the random access suspension comprises alternative carrier information indicating the second UL CC.

4. The method of claim 3, wherein the information regarding the random access suspension further comprises one of a suspending parameter, a type discrimination indicator indicating whether a random access preamble identifier is includes or not, and an access suspension indicator indicating whether the random access suspension includes or not;

and

wherein the information regarding the random access suspension is configured as a medium access control (MAC) message subheader.

5. The method of claim 4, wherein the suspending parameter comprises information regarding a suspending time or information regarding a combination of the suspending time and a suspending object, and the suspending time indicates a duration for suspending the second random access,

wherein the suspending object indicates a CC or a cell in which the second random access is suspended, and

wherein each of the information regarding the combination of the suspending time and the suspending object and the information regarding the suspending time is configured specifically to a CC or to the mobile station.

6. The method of claim 4, wherein each of the information regarding the combination of the suspending time and the suspending object and the information regarding the suspending time is configured specifically to a primary CC (PCC).

7. The method of claim 4, wherein each of the information regarding the combination of the suspending time and the suspending object and the information regarding the suspending time is configured specifically to a secondary CC (SCC).

8. The method of claim 4, wherein the information regarding the random access suspending further comprises a suspending parameter, and the suspending parameter is configured Cell-specific linked CC.

9. The method of claim 4, wherein the information regarding the suspension of the random access further comprises a suspending parameter, and the suspending parameter is configured UE-specific linked CC.

10. The method of claim 4, further comprising:

checking if a triggering condition for triggering a second random access is met; and

if the triggering condition is met, transmitting a second random access preamble to the BS through a second UL CC.

11. A method for performing a random access by a base station (BS) in a multi-carrier system, the method comprising:

receiving a first random access preamble on an uplink (UL) component carrier (CC) from a first mobile station (MS);

transmitting a random access response (RAR) on a first downlink (DL) CC linked to the UL CC;

receiving an uplink message from the first MS on a UL resource indicated by the RAR; and

transmitting a contention resolution (CR) message on a second DL CC, the CR message indicating that a collision of the first random access preamble and a second random access preamble of other MSs are resolved,

wherein the RAR comprises information regarding the second DL CC.

12. The method of claim 11, wherein the RAR comprises timing advance (TA) information and an uplink grant, and the uplink message is received based on the TA information and the uplink grant.

13. A base station (BS) to perform a random access in a multi-carrier system, the BS comprising:

a preamble reception unit to receive a first random access preamble on a first uplink (UL) component carrier (CC) from a first mobile station (MS) performing a first random access;

a response generation unit to generate a random access response (RAR) comprising first information and second information, the first information to suspend a second random access if the first random access is not successful, the second information identifying a second UL CC to perform the second random access if the second random access is triggered; and

a response transmission unit to transmit the RAR to the first MS by using a first downlink (DL) CC linked to the first UL CC.

14. The base station of claim 13, wherein the preamble reception unit receives a second random access preamble from the first MS if the second random access is triggered.

15. The base station of claim 13, wherein the base station sends a contention resolution (CR) message on the second DL CC if a collision of the first random access preamble and a third random access preamble of a second MS is resolved.

16. A first mobile station (MS) to perform a random access in a multi-carrier system, the first MS comprising:

a preamble transmission unit to transmit a first random access preamble on a first uplink (UL) component carrier (CC) to a base station (BS);

a response reception unit to receive a random access response (RAR) on a first downlink (DL) CC linked to the first UL CC;

a carrier configuration unit to configure a second DL CC; and

a message reception unit to receive a contention resolution (CR) message on the second DL CC, the CR message indicating a resolution of a collision of the first random access preamble and a second random access preamble of a second MS, wherein the RAR comprises information regarding the second DL CC.

17. The first MS of claim 16, wherein if a triggering condition for triggering a third random access is met, the preamble transmission unit transmits a third random access preamble to the BS through a third UL CC.

18. The first MS of claim 16, wherein the RAR comprises a suspending parameter indicating a suspending time of the third random access, and further comprises alternative carrier information indicating the third UL CC.