PERFORMING RANDOM ACCESS PROCEDURES USING EXTENDED RANDOM ACCESS RESPONSE

• US 20110170503A1
• Filed: 08/05/2009
• Published: 07/14/2011
• Est. Priority Date: 08/07/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Yi, Seung-June, Park, Sung-Jun, Lee, Young-Dae, Chun, Sung-Duck
• Granted Patent: US 8,761,096 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• 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 74/0838 using contention-free random access [CFRA]

Abstract

A random access procedure is performed by receiving information related to a random access preamble, the information indicating a first random access preamble related to a first format and a second random access preamble related to a second format; selecting a random access preamble according to the received information; transmitting the selected random access preamble; receiving a random access response; and decoding the received random access response according to the format associated with the selected random access preamble.

Claims

1. A method of random access procedure, comprising:

receiving information related to a random access preamble, the information indicating a first random access preamble related to a first format and a second random access preamble related to a second format;

selecting a random access preamble according to the received information;

transmitting the selected random access preamble;

receiving a random access response; and

decoding the received random access response according to the format associated with the selected random access preamble.

2. The method of claim 1, wherein the information is received via a system information block (SIB).

3. The method of claim 1, wherein the first format is associated with mobile terminals supporting Rel-8 or mobile terminals supporting LTE.

4. The method of claim 1, wherein the second format is associated with mobile terminals supporting Rel-9 or mobile terminals supporting LTE-Advanced.

5. The method of claim 1, wherein the random access response is received as a MAC PDU having a MAC header and MAC payload.

6. The method of claim 5, wherein the MAC payload comprises at least one MAC random access response (RAR), each MAC RAR comprising information about an uplink grant and a Temporary C-RNTI.

7. The method of claim 6, wherein the MAC RAR further includes an R bit used for indicating the first format or the second format associated with the selected random access preamble.

8. The method of claim 1, wherein the received random access response comprises one or more first messages having a Random Access RNTI1 (RA-RNTI1) related to the first format, and one or more second messages having a Random Access RNTI2 (RA-RNTI2) related to the second format.

9. The method of claim 1, wherein the received random access response comprises a single message containing at least one Random Access RNTI1 (RA-RNTI1) and at least one Random Access RNTI2 (RA-RNTI2).

10. The method of claim 1, wherein the received random access response comprises one or more Normal RAR elements and one or more Extended RAR elements.

11. The method of claim 10, wherein each Normal RAR element and each Extended RAR element has a length of 6 bytes.

12. The method of claim 10, wherein the received random access response further comprises a length field to indicate a length of at least one of the Extended RAR elements.

13. The method of claim 10, wherein the Extended RAR elements are positioned after all of the Normal RAR elements.

14. A mobile terminal comprising:

means for receiving information related to a random access preamble, the information indicating a first random access preamble related to a first format and a second random access preamble related to a second format;

means for selecting a random access preamble according to the received information;

means for transmitting the selected random access preamble;

means for receiving a random access response; and

means for decoding the received random access response according to the format associated with the selected random access preamble.

15. A network that performs a method of random access procedure, comprising:

means for transmitting information related to a random access preamble, the information indicating a first random access preamble related to a first format and a second random access preamble related to a second format;

means for receiving a particular random access preamble that was selected according to the transmitted information; and

means for transmitting a random access response to be decoded according to the first format or the second format associated with the selected random access preamble.