Method and apparatus of operating multiple time alignment timers in mobile communication system supporting carrier aggregation

• US 10,582,480 B2
• Filed: 04/05/2012
• Issued: 03/03/2020
• Est. Priority Date: 04/05/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jang, Jaehyuk, Jeong, Kyeong In
• Primary Examiner(s): Young, Steve R
• Application Number:
  US13/440,216
• Publication Number:
  US 20120257570A1
• Time in Patent Office: 2,889 Days
• Field of Search: None
• CPC Class Codes: H04L 1/1835 Buffer management
• CPC Class Codes: H04L 1/1851 using multiple timers
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/1883 using multiple timers
• CPC Class Codes: H04L 27/2662 Symbol synchronisation
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 56/005 : compensating for timing error by adjustment in the receiver
• CPC Class Codes: H04W 72/00 : Local resource management
• CPC Class Codes: H04W 72/04 : Wireless resource allocation
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/21 : in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• 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 74/085 : collision avoidance
• CPC Class Codes: H04W 74/0858 : collision detection
• CPC Class Codes: H04W 74/0891 : for synchronized access
• CPC Class Codes: H04W 76/19 : Connection re-establishment
• CPC Class Codes: H04W 76/38 : triggered by timers
• CPC Class Codes: H04W 84/042 : Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A method of operating multiple time alignment timers (TimeAlignmentTimer) is provided for facilitating communication between and evolved Node B (eNB) and a User Equipment (UE) in a Long Term Evolution (LTE) system supporting multiple carriers. The method includes starting a first TAT of a first group including the primary cell, starting a second TAT when Timing Advance (TA) information on a second group not including the primary cell is received; and determining transmission of at least one of a Hybrid Automatic Repeat Request Acknowledgement/Negative-acknowledgement (HARQ ACK/NACK), a physical uplink control channel, and a sounding reference signal according to a start and an expiration of at least one of the first and second TATs.

Claims

1. A method for operating time alignment timers (TATs) of a user equipment (UE) transmitting/receiving data to/from an evolved node B (eNB) on a primary cell (PCell) and at least one secondary cell (SCell), the method comprising:

receiving, from the eNB, first timing advance (TA) information associated with a primary timing advance group (PTAG) which is a group of serving cells having a same uplink timing and includes the PCell;

starting or restarting a first TAT associated with the PTAG based on the first TA information;

receiving, from the eNB, second TA information associated with a secondary timing advance group (STAG) which is a group of serving cells having a same uplink timing and does not include the PCell;

starting or restarting a second TAT associated with the STAG based on the second TA information;

receiving downlink data on at least one serving cell in the STAG;

identifying whether the first TAT associated with the PTAG is running and whether the second TAT associated with the STAG is running;

delivering hybrid automatic repeat request (HARQ) positive or negative acknowledgement (ACK/NACK) information corresponding to the downlink data received on the at least one serving cell in the STAG to a physical (PHY) layer of the UE, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running; and

flushing all HARQ buffers for all serving cells in the PTAG and the STAG, in case that the first TAT associated with the PTAG expires and the second TAT associated with the STAG is running or expires.

2. The method of claim 1, wherein the first TA information and the second TA information is received in a timing advance command media access control (MAC) control element or in a random access response message.

3. The method of claim 2, wherein the random access response message is transmitted from the eNB, in response to a transmission of random access preamble by the UE according to a physical downlink control channel (PDCCH) order from the eNB.

4. The method of claim 1, further comprising:

notifying a radio resource control (RRC) to release a sounding reference signal (SRS) for serving cells belonging to the STAG, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running.

5. The method of claim 1, further comprising:

suspending delivery of HARQ ACK/NACK information to the PHY layer, in case that the first TAT associated with the PTAG expires.

6. The method of claim 1, further comprising:

suspending delivery of HARQ ACK/NACK information to the PHY layer, in case that the first TAT associated with the PTAG expires and the second TAT associated with the STAG expires.

7. The method of claim 4, wherein the notifying of the RRC to release the SRS comprises delivering an identifier (ID) of the STAG.

8. The method of claim 1, further comprising:

transmitting a HARQ ACK/NACK, corresponding to data received on the at least one serving cell in the STAG, to the eNB through the PCell, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running.

9. The method of claim 1, further comprising:

suspending uplink data transmission, in case that the first TAT associated with the PTAG expires.

10. The method of claim 1, further comprising:

notifying a radio resource control (RRC) to release a physical uplink control channel (PUCCH)/a sounding reference signal (SRS) for all serving cells, in case that the first TAT associated with the PTAG expires.

11. A user equipment (UE) operating time alignment timers (TATs), the UE comprising:

a transceiver; and

a controller configured to;

control the transceiver to receive, from an evolved node B (eNB), first timing advance (TA) information associated with a primary timing advance group (PTAG) which is a group of serving cells having a same uplink timing and includes a primary cell (PCell),

start or restart a first TAT associated with the PTAG based on the first TA information,

control the transceiver to receive, from the eNB, second TA information associated with a secondary timing advance group (STAG) which is a group of serving cells having a same uplink timing and does not include the PCell,

start or restart a second TAT associated with the STAG based on the second TA information,

control the transceiver to receive downlink data on at least one serving cell in the STAG,

identify whether the first TAT associated with the PTAG is running and whether the second TAT associated with the STAG is running,

deliver hybrid automatic repeat request (HARQ) positive or negative acknowledgement (ACK/NACK) information corresponding to the downlink data received on the at least one serving cell in the STAG to a physical (PHY) layer of the UE, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running, and

flush all HARQ buffers for all serving cells, in case that the first TAT associated with the PTAG expires and the second TAT associated with the STAG is running or expires.

12. The UE of claim 11, wherein the controller is further configured to control the transceiver to receive the first TA information and the second TA information in a timing advance command media access control (MAC) control element or in a random access response message.

13. The UE of claim 12, wherein the random access response message is transmitted from the eNB, in response to a transmission of a random access preamble by the UE according to a physical downlink control channel (PDCCH) order from the eNB.

14. The UE of claim 11, wherein the controller is further configured to notify a radio resource control (RRC) to release a sounding reference signal (SRS) for serving cells belonging to the STAG, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running.

15. The UE of claim 11, wherein the controller is further configured to suspend delivery of HARQ ACK/NACK information to the PHY layer, in case that the first TAT associated with the PTAG expires.

16. The UE of claim 11, wherein the controller is further configured to suspend delivery of HARQ ACK/NACK information to the PHY layer, in case that the first TAT associated with the PTAG expires and the second TAT associated with the STAG expires.

17. The UE of claim 14, wherein the notifying of the RRC to release the SRS comprises delivering an identifier (ID) of the STAG.

18. The UE of claim 11, wherein the controller is further configured to control the transceiver to transmit a HARQ ACK/NACK, corresponding to data received on the at least one serving cell in the STAG, to the eNB through the PCell, in case that the second TAT associated with the STAG expires and the first TAT associated with the PTAG is running.

19. The UE of claim 11, wherein the controller is further configured to suspend uplink data transmission, in case that the first TAT associated with the PTAG expires.

20. The UE of claim 11, wherein the controller is further configured to notify a radio resource control (RRC) to release a physical uplink control channel (PUCCH)/a sounding reference signal (SRS) for all serving cells, in case that the first TAT associated with the PTAG expires.