METHOD OF PERFORMING UPLINK TIME ALIGNMENT IN WIRELESS COMMUNICATION SYSTEM

• US 20100195640A1
• Filed: 09/26/2008
• Published: 08/05/2010
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Sung Jun, Lee, Young Dae, Yi, Seung June, Chun, Sung Duck
• Granted Patent: US 8,432,811 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

A method of performing uplink time alignment in wireless communication system includes transmitting a random access preamble, receiving a random access response, the random access response comprising a random access preamble identifier corresponding to the random access preamble but no time alignment value, and restarting a time alignment timer according to receiving the random access response.

Claims

1. A method of performing uplink time alignment in wireless communication system, the method comprising:

transmitting a random access preamble;

receiving a random access response, the random access response comprising a random access preamble identifier corresponding to the random access preamble but no time alignment value; and

restarting a time alignment timer according to receiving the random access response.

2. The method of claim 1, wherein the random access preamble is a dedicated random access preamble which is previously assigned by a base station.

3. The method of claim 1, wherein the time alignment timer is running before the random access preamble is transmitted.

4. The method of claim 1, further comprising:

receiving the value of the time alignment timer and the random access preamble from a base station.

5. The method of claim 4, further comprising:

starting the time alignment timer after applying the value of the time alignment timer.

6. The method of claim 4, wherein the value of the time alignment timer and the random access preamble are received as a part of system information.

7. The method of claim 4, wherein the value of the time alignment timer and the random access preamble are received through a handover command message.

8. The method of claim 4, wherein the value of the time alignment timer is set to infinity.

9. The method of claim 1, wherein the random access response is a MAC (medium access control) PDU (protocol data unit), the MAC PDU comprising a MAC header and at least one MAC random access response (RAR), the MAC header comprising at least MAC subheader, each MAC subheader corresponding to a MAC RAR, a MAC subheader comprising the random access preamble identifier.

10. The method of claim 9, wherein the MAC RAR comprises an uplink resource assignment and a temporary Cell-Radio Network Temporary Identity (C-RNTI).

11. A method of performing uplink time alignment in wireless communication system, the method comprising:

transmitting a dedicated random access preamble;

receiving a random access response, the random access response comprising a random access preamble identifier corresponding to the dedicated random access preamble; and

restarting a time alignment timer according to receiving the random access response.

12. The method of claim 11, further comprising:

receiving information on the dedicated random access preamble from a base station.

13. The method of claim 11, further comprising:

starting the time alignment timer before the dedicated random access preamble is transmitted.

14. The method of claim 13, further comprising:

receiving a time alignment value, wherein the time alignment timer is started after applying the time alignment value.