METHOD AND APPARATUS FOR MANAGING MULTIPLE TIMING ADVANCE GROUPS IN MOBILE COMMUNICATION SYSTEM SUPPORTING CARRIER AGGREGATION

• US 20120257601A1
• Filed: 04/05/2012
• Published: 10/11/2012
• Est. Priority Date: 04/05/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: KIM, Sangbum, JEONG, Kyeongin
• Granted Patent: US 9,491,782 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• 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 and apparatus for managing multiple Timing Advance Groups (TAGs) operating with different timings are provided for use in a Long Term Evolution (LTE) system. The method for managing multiple TAGs at a base station of a wireless communication system supporting carrier aggregation according to an exemplary embodiment of the present invention includes categorizing a plurality of carriers into at least one TAG according to a predetermined rule, assigning a TAG index to each TAG, transmitting the TAG index to a terminal, generating a Timing Advance Command (TAC) for synchronization, and transmitting the TAC to the terminal in a random access process. The method and apparatus for managing TAGs according to exemplary embodiments of the present invention is capable of informing of the timing advance group to which each carrier belongs and managing multiple timing advance groups efficiently without signaling overhead.

Claims

1. A method for managing multiple Timing Advance Groups (TAGs) at a base station of a wireless communication system supporting carrier aggregation, the method comprising:

categorizing a plurality of carriers into at least one TAG according to a predetermined rule;

assigning a TAG index to each TAG;

transmitting the TAG index to a terminal;

generating a Timing Advance Command (TAC) for synchronization; and

transmitting the TAC to the terminal in a random access process.

2. The method of claim 1, wherein the assigning of the TAG index to each TAG comprises:

allocating a highest TAG index to a primary cell (PCell);

determining whether a secondary cell (SCell) belongs to the same TAG as the PCell; and

skipping, when the SCell belongs to the same TAG as the PCell, assignment of a TAG index to the SCell.

3. The method of claim 2, wherein the assigning of the TAG index to each TAG comprises:

determining, when the SCell does not belong to the same TAG as the PCell, whether another secondary carrier exists in the same TAG; and

assigning, when no other secondary carrier exists in the same TAG, a new TAG index to the secondary carrier.

4. The method of claim 3, wherein the assigning of the TAG index to each TAG comprises skipping, when another second carrier exists in the same TAG, assignment of the new TAG index to the SCell.

5. The method of claim 1, wherein the assigning of the TAG index to each TAG comprises allocating the TAG indices to all of the carriers, respectively.

6. The method of claim 1, wherein the categorizing of the plurality of carriers into at least one TAG comprises grouping the carriers having uplink timings in a predetermined range into a TAG.

7. A method for managing multiple Timing Advance Groups (TAGs) at a terminal of a wireless communication system supporting a carrier aggregation technique, the method comprising:

receiving a TAG index per TAG according to a predetermined rule;

applying the received TAG indices;

receiving timing advance command from a base station in random access process; and

acquiring synchronization according to the received timing advance command.

8. The method of claim 7, wherein the applying of the received TAG indices comprises:

applying the TAG index allocated to a primary carrier;

determining whether a TAG index is allocated to a secondary carrier; and

applying, when a TAG index is allocated to a secondary carrier, the TAG index.

9. The method of claim 8, wherein the applying of the received TAG indices comprises applying, when no TAG index is allocated to the secondary carrier, the TAG index of another secondary carrier belonged to the corresponding TAG and having a TAG index.

10. The method of claim 7, wherein the acquiring of synchronization according to the received timing advance command comprises configuring uplink timings according to the timing advance command.

11. A base station for managing multiple Timing Advance Groups (TAGs) in a wireless communication system supporting a carrier aggregation technique, the base station comprising:

a transceiver which transmits and receives data; and

a controller which controls categorizing a plurality of carriers into at least one TAG according to a predetermined rule, assigning a TAG index to each TAG, transmitting the TAG index to a terminal, generating a Timing Advance Command (TAC) for synchronization, and transmitting the TAC to the terminal in a random access process.

12. The base station of claim 11, wherein the controller allocates a highest TAG index to a primary cell (PCell), determines whether a secondary cell (SCell) belongs to the same TAG as the PCell, and skips, when the SCell belongs to the same TAG as the PCell, assignment of a TAG index to the SCell.

13. The base station of claim 12, wherein the controller determines, when the SCell does not belong to the same TAG as the PCell, whether another secondary carrier exists in the same TAG and assigns, when no other secondary carrier exists in the same TAG, a new TAG index to the secondary carrier.

14. The base station of claim 13, wherein the controller skips, when another second carrier exists in the same TAG, assignment of TAG index to the SCell.

15. The base station of claim 11, wherein the controller assigns the TAG indices to all of the carriers, respectively.

16. The base station of claim 11, wherein the controller groups the carriers having uplink timings in a predetermined range into a TAG.

17. A terminal for managing multiple Timing Advance Groups (TAGs) in a wireless communication system supporting a carrier aggregation technique, the terminal comprising:

a transceiver which transmits and receives data; and

a controller which controls receiving a TAG index per TAG according to a predetermined rule, applying the received TAG indices, receiving timing advance command from a base station in random access process, and acquiring synchronization according to the received timing advance command.

18. The terminal of claim 17, wherein the controller controls applying the TAG index allocated to a primary carrier, determining whether a TAG index is allocated to a secondary carrier, and applying, when a TAG index is allocated to a secondary carrier, the TAG index.

19. The terminal of claim 18, wherein the controller controls applying, when no TAG index is allocated to the secondary carrier, the TAG index of another secondary carrier belonged to the corresponding TAG and having a TAG index.

20. The terminal of claim 17, wherein the controller controls configuring uplink timings according to the timing advance command in acquiring synchronization according to the received timing advance command.