METHOD FOR SIGNALING BACK-OFF INFORMATION IN RANDOM ACCESS

• US 20110216706A1
• Filed: 05/13/2011
• Published: 09/08/2011
• Est. Priority Date: 01/31/2008
• Status: Active Grant

• Current Assignee: Park Sung Jun, Seung-June Yi, Sung-Duck Chun, Young-Dae Lee
• Original Assignee: Park Sung Jun, Seung-June Yi, Sung-Duck Chun, Young-Dae Lee
• Inventors: Park, Sung Jun, Lee, Young Dae, Yi, Seung June, Chun, Sung Duck
• Granted Patent: US 8,532,135 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A method for performing random access in a wireless communication system is provided. The method includes transmitting a preamble for random access in uplink, receiving a random access response message including back-off information as a response to the preamble, and performing back-off using the back-off information when the random access has failed.

Claims

1. A method for performing a random access procedure in a wireless communication system, the method comprising:

transmitting a preamble for random access from a mobile station to a base station; and

receiving by the mobile station a random access response message from the base station as a response to the preamble, the random access response message having a MAC (Medium Access Control) header and zero or more MAC random access responses (RARs),

wherein the MAC header comprises a MAC sub-header, wherein the MAC sub-header consists of 8 bits including a first bit directly followed by a second bit, and the MAC sub-header starts with the first bit,

wherein the first bit indicates whether or not more fields are included in the MAC header,

wherein the second bit indicates a backoff parameter, and

wherein, when the second bit indicates the MAC sub-header has the backoff parameter, the random access response message has no MAC RAR.

2. The method of claim 1, further comprising:

performing backoff using the backoff parameter in the random access response message.

3. The method of claim 1, wherein the backoff parameter is a common backoff parameter or an exclusive backoff parameter to be used exclusively by the mobile terminal.

4. The method of claim 1, wherein the second bit indicating the backoff parameter is directly followed by the backoff parameter.

5. A method for performing a random access procedure by a base station in a wireless communication system, the method comprising:

receiving, by the base station, a preamble for random access from a mobile station; and

transmitting, by the base station, to the mobile station a random access response message as a response to the preamble, the random access response message having a MAC (Medium Access Control) header and zero or more MAC random access responses (RARs),

wherein the MAC header comprises a MAC sub-header, wherein the MAC sub-header consists of 8 bits including a first bit directly followed by a second bit, and the MAC sub-header starts with the first bit,

wherein the first bit indicates whether or not more fields are included in the MAC header,

wherein the second bit indicates a backoff parameter, and

wherein, when the second bit indicates the MAC sub-header has the backoff parameter, the random access response message has no MAC RAR.

6. The method of claim 5, wherein the backoff parameter in the random access response message is configured to enable the mobile terminal to perform backoff using the backoff parameter.

7. The method of claim 5, wherein the backoff parameter is a common backoff parameter or an exclusive backoff parameter to be used exclusively by the mobile terminal.

8. The method of claim 5, wherein the second bit indicating the backoff parameter is directly followed by the backoff parameter.

9. A mobile terminal configured to perform a random access procedure in a wireless communication system, comprising:

a processor configured to cause the mobile terminal to

transmit a preamble for random access to a base station, and

receive a random access response message from the base station as a response to the preamble, the random access response message having a MAC (Medium Access Control) header and zero or more MAC random access responses (RARs),

wherein the MAC header comprises a MAC sub-header, wherein the MAC sub-header consists of 8 bits including a first bit directly followed by a second bit, and the MAC sub-header starts with the first bit,

wherein the first bit indicates whether or not more fields are included in the MAC header,

wherein the second bit indicates a backoff parameter, and

wherein, when the second bit indicates the MAC sub-header has the backoff parameter, the random access response message has no MAC RAR.

10. The mobile terminal of claim 9, wherein the processor is configured to cause the mobile terminal to perform backoff using the backoff parameter in the random access response message.

11. The mobile terminal of claim 9, wherein the backoff parameter is a common backoff parameter or an exclusive backoff parameter to be used exclusively by the mobile terminal.

12. The mobile terminal of claim 9, wherein the second bit indicating the backoff parameter is directly followed by the backoff parameter.

13. A network configured to perform a random access procedure in a wireless communication system, comprising:

a processor configured to

receive a preamble for random access from a mobile station, and

transmit to the mobile station a random access response message as a response to the preamble, the random access response message having a MAC (Medium Access Control) header and zero or more MAC random access responses (RARs),

wherein the MAC header comprises a MAC sub-header, wherein the MAC sub-header consists of 8 bits including a first bit directly followed by a second bit, and the MAC sub-header starts with the first bit,

wherein the first bit indicates whether or not more fields are included in the MAC header,

wherein the second bit indicates a backoff parameter, and

wherein, when the second bit indicates the MAC sub-header has the backoff parameter, the random access response message has no MAC RAR.

14. The network of claim 13, wherein the backoff parameter in the random access response message is configured to enable the mobile terminal to perform backoff using the backoff parameter.

15. The network of claim 13, wherein the backoff parameter is a common backoff parameter or an exclusive backoff parameter to be used exclusively by the mobile terminal.

16. The network of claim 13, wherein the second bit indicating the backoff parameter is directly followed by the backoff parameter.