METHOD AND APPARATUS FOR ACTIVATING OR DEACTIVATING SECONDARY CARRIERS IN TIME DIVISION DUPLEX MOBILE COMMUNICATION SYSTEM USING CARRIER AGGREGATION

• US 20120213129A1
• Filed: 02/21/2012
• Published: 08/23/2012
• Est. Priority Date: 02/21/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: JANG, Jaehyuk, KIM, Soenghun
• Granted Patent: US 8,867,466 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• 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 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0078 Timing of allocation
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• 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

Abstract

A method and an apparatus for activating or deactivating a primary carrier and secondary carriers in a Time Division Duplex Long Term Evolution (TDD LTE) system using carrier aggregation are provided. An apparatus includes an User Equipment employing the method corresponding the operation associated with the activation and deactivation of SCells, which thereby performs communication with eNBs without errors.

Claims

1. A method for controlling secondary carriers for User Equipment (UE) in Time Division duplex (TDD) mobile communication system using Carrier Aggregation (CA), the method comprising:

receiving, by the UE, a secondary carrier control message for activating or deactivating the secondary carriers from Evolved Node Bs (eNBs);

operating a timer if the secondary carrier control message corresponds to a message for activating a particular secondary carrier; and

activating the forward direction of the particular secondary carrier in a downlink sub-frame arrived first after the timer has expired.

2. The method of claim 1, further comprising:

determining, after the timer has expired, whether a special sub-frame existed during the operation of the timer; and

activating, if a special sub-frame existed during the operation of the timer, the reverse direction of the particular secondary carrier in a sub-frame without a Physical Downlink Channel (PHDCH) arrived first after the timer has expired, or in the special sub-frame.

3. The method of claim 2, further comprising:

activating, if the special sub-frame did not exist during the operation of the timer, the reverse direction of the particular secondary carrier in a special sub-frame arrived first after the timer has expired, or in a sub-frame following the first special sub-frame.

4. The method of claim 3, wherein the activation of the reverse direction of a secondary carrier comprises at least one of:

reporting Channel State Information (CSI); and

transmitting Sounding Reference Symbols (SRS).

5. The method of claim 2, further comprising:

performing, if the special sub-frame did not exist during the operation of the timer, a first operation in a special sub-frame arrived first after the timer has expired; and

performing a second operation in a sub-frame following the special sub-frame arrived first after the timer has expired.

6. The method of claim 5, wherein:

the first operation comprises transmitting symbols in the reverse direction; and

the second operation comprises transmission via Physical Uplink Shared Channel (PUSCH).

7. The method of claim 1, further comprising:

operating the timer if the secondary carrier control message corresponds to a message for deactivating a particular secondary carrier; and

deactivating the forward direction of the particular secondary carrier in a downlink sub-frame arrived first after the timer has expired.

8. The method of claim 7, further comprising:

determining, after the timer has expired, whether a special sub-frame existed during the operation of the timer; and

deactivating, if a special sub-frame existed during the operation of the timer, the reverse direction of the particular secondary carrier in a sub-frame without a Physical Downlink Channel (PHDCH) arrived first after the timer has expired, or in the special sub-frame.

9. The method of claim 8, further comprising:

deactivating, if the special sub-frame did not exist during the operation of the timer, the reverse direction of the particular secondary carrier in a special sub-frame arrived first after the timer has expired, or in a sub-frame following the first special sub-frame.

10. The method of claim 1, wherein a preset time interval of the timer is a time corresponding to 8 sub-frames.

11. User Equipment (UE) for controlling secondary carriers in a Time Division Duplex (TDD) mobile communication system using Carrier Aggregation (CA), the User Equipment comprising:

a transceiver for transmitting to or for receiving symbols from an Evolved Node B (eNB); and

a controller for receiving a secondary carrier control message for activating or for deactivating the secondary carriers from the eNB, for operating a timer if the secondary carrier control message corresponds to a message for activating a particular secondary carrier, and for activating the forward direction of the particular secondary carrier in a downlink sub-frame arrived first after the timer has expired.

12. The User Equipment of claim 11, wherein the controller is configured to:

determine, after the timer has expired, whether a special sub-frame existed during the operation of the timer; and

activate, if a special sub-frame existed during the operation of the timer, the reverse direction of the particular secondary carrier in a sub-frame without a Physical Downlink Channel (PHDCH) arrived first after the timer has expired or in the special sub-frame.

13. The User Equipment of claim 12, wherein the controller the controller is configured to activate, if the special sub-frame did not exist during the operation of the timer, the reverse direction of the particular secondary carrier in a special sub-frame arrived first after the timer has expired or in a sub-frame following the first special sub-frame.

14. The User Equipment of claim 13, wherein the controller is configured to activate the reverse direction of a secondary carrier in order to perform at least one of reporting Channel State Information (CSI), and transmitting Sounding Reference Symbols (SRS).

15. The User Equipment of claim 11, wherein the controller is configured to perform a first operation in a special sub-frame arrived first after the timer has expired if the special sub-frame did not exist during the operation of the timer, and a second operation in a sub-frame following the special sub-frame arrived first after the timer has expired.

16. The User Equipment of claim 15, wherein:

the first operation comprises transmitting symbols in the reverse direction; and

the second operation comprises transmission via a Physical Uplink Shared Channel (PUSCH).

17. The User Equipment of claim 11, wherein the controller is configured to:

operate the timer if the secondary carrier control message corresponds to a message for deactivating a particular secondary carrier; and

deactivate the forward direction of the particular secondary carrier in a downlink sub-frame arrived first after the timer has expired.

18. The User Equipment of claim 17, wherein the controller is configured to:

determine, after the timer has expired, whether a special sub-frame existed during the operation of the timer; and

deactivate, if a special sub-frame existed during the operation of the timer, the reverse direction of the particular secondary carrier in a sub-frame without a Physical Downlink Channel (PHDCH) arrived first after the timer has expired, or in the special sub-frame.

19. The User Equipment of claim 18, wherein the controller deactivates, if the special sub-frame did not exist during the operation of the timer, the reverse direction of the particular secondary carrier in a special sub-frame arrived first after the timer has expired or in a sub-frame following the first special sub-frame.

20. The User Equipment of claim 11, wherein a preset time interval of the timer is a time corresponding to 8 sub-frames.