METHOD AND APPARATUS FOR OBTAINING UPLINK TIMING ALIGNMENT ON A SECONDARY CELL

• US 20120300715A1
• Filed: 05/10/2012
• Published: 11/29/2012
• Est. Priority Date: 05/10/2011
• Status: Abandoned Application

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Pelletier, Ghyslain, Marinier, Paul, Shin, Sung-Hyuk, Stern-Berkowitz, Janet A.
• Application Number:
  US13/468,709
• Publication Number:
  US 20120300715A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• 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 74/0891 for synchronized access

Abstract

A method for uplink timing alignment in a wireless transmit/receive unit. The method includes receiving control signaling from an evolved Node B, receiving a message for Random Access Channel on a secondary cell, and completing the RACH upon receipt of the message, wherein the message includes a medium access control (MAC) control element with at least an 11-bit time advance command.

Claims

1. A method for uplink timing alignment in a wireless transmit/receive unit (WTRU), the method comprising:

receiving control signaling from an evolved Node B (eNB);

receiving a message for Random Access Channel (RACH) on a secondary cell (SCell);

completing the RACH upon receipt of the message; and

wherein the message includes a medium access control (MAC) control element (CE) with at least an 11-bit time advance command (TAC).

2. The method of claim 1, wherein the MAC CE is scheduled by a Cell Radio Network Temporary Identifier (C-RNTI).

3. The method of claim 1, wherein the MAC CE is scheduled on any physical downlink control channel (PDCCH) in a WTRU specific search space (SS).

4. The method of claim 1, wherein the MAC CE is received using a HARQ process.

5. The method of claim 1, wherein the MAC CE is received in a MAC packet data unit (PDU) multiplexed with other data.

6. The method of claim 1, further comprising:

receiving a PDCCH order.

7. The method of claim 6, further comprising:

maintaining a count of a number of preamble retransmissions for power ramping.

8. The method of claim 7, further comprising:

resetting the count when the message is received.

9. The method of claim 7, further comprising:

resetting the count when a preamble transmission is triggered on a different SCell.

10. The method of claim 7, further comprising:

resetting the count when an activation state or a configuration state of the SCell or of a Timing Advance Group (TAG) of the SCell changes.

11. The method of claim 7, further comprising:

resetting the count when an indication that a request is for an initial preamble transmission for the SCell is received in the control signaling for the PDCCH order.

12. The method of claim 6, further comprising:

applying an amount of power ramping using a value received in control signaling in the PDCCH order.

13. The method of claim 6, further comprising:

maintaining a count when an indication is that the request is for a preamble retransmission for the SCell is received in control signaling for the PDCCH order.

14. A wireless transmit/receive unit (WTRU) for uplink timing alignment, comprising:

a receiver configured to receive control signaling from an evolved Node B (eNB);

the receiver further configured to receive a message for RACH on a secondary cell (SCell);

a processor configured to complete the RACH upon receipt of the message; and

wherein the message includes a medium access control (MAC) control element (CE) with at least an 11-bit time advance command (TAC).

15. The WTRU of claim 14, wherein the MAC CE is scheduled by a Cell Radio Network Temporary Identifier (C-RNTI).

16. The WTRU of claim 14, wherein the MAC CE is scheduled on any physical downlink control channel (PDCCH) in a WTRU specific search space (SS).

17. The WTRU of claim 14, wherein the MAC CE is received using a HARQ process.

18. The WTRU of claim 14, wherein the MAC CE is received in a MAC packet data unit (PDU) multiplexed with other data.

19. The WTRU of claim 14, wherein the receiver is further configured to receive a PDCCH order.

20. The WTRU of claim 19, wherein the processor is further configured to maintain a count of a number of preamble retransmissions for power ramping.