Method and apparatus for controlling random access in wireless communication system supporting carrier aggregation

• US 8,824,310 B2
• Filed: 04/05/2012
• Issued: 09/02/2014
• Est. Priority Date: 04/05/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jeong, Kyeong In, Van Lieshout, Gert-Jan
• Primary Examiner(s): Zhou, Yong
• Application Number:
  US13/440,152
• Publication Number:
  US 20120257510A1
• Time in Patent Office: 880 Days
• US Class Current: 370/242
• 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 random access procedure control method and apparatus is provided for controlling a random access procedure efficiently in a mobile communication system supporting carrier aggregation. The method for controlling random access procedure of a terminal in a wireless communication system having a primary cell and at least one secondary cell includes initiating a random access procedure in the primary cell and the at least one secondary cells, detecting a random access failure of a terminal performing the random access procedure, determining whether the random access failure is detected in the primary cell or the at least one secondary cell, and determining whether to continue the random access procedure according to a result of the determining of whether the random access failure is detected.

Claims

1. A method for controlling a random access procedure by a terminal in a wireless communication system, the method comprising:

transmitting a random access preamble to a base station;

determining whether the random access preamble is transmitted on a primary cell or a secondary cell if a random access problem is detected;

indicating the random access problem to upper layers if the random access preamble is transmitted on the primary cell; and

stopping the random access procedure if the random access preamble is transmitted on the secondary cell.

2. The method of claim 1, further comprising executing, if the random access problem is detected on the primary cell, a radio resource control (RRC) connection re-establishment procedure.

3. The method of claim 2, further comprising:

executing the RRC connection re-establishment procedure if the random access problem is detected on the primary cell and is not solved.

4. The method of claim 3, wherein the executing of the RRC connection re-establishment further comprises:

starting a timer if the random access problem is detected on the primary cell; and

stopping the executing of the RRC connection re-establishment procedure upon expiration of the timer.

5. The method of claim 1, wherein the determining of whether the random access problem is detected comprises determining that the random access has failed if the number of transmissions of the random access preamble reaches to a predetermined value.

6. The method of claim 1, wherein the random access problem is detected if a random access response is not received from the base station.

7. A terminal for attempting random access to a base station in a wireless communication system having a primary cell and at least one secondary cell, the terminal comprising:

a transceiver for communicating signals with the base station; and

a controller for transmitting a random access preamble to a base station, for determining whether the random access preamble is transmitted on a primary cell or a secondary cell if random access problem is detected, indicating the random access problem to upper layers if the random access preamble is transmitted on the primary cell, and for stopping the random access procedure if the random access preamble is transmitted on the secondary cell.

8. The terminal of claim 7, wherein the controller executes, if the random access problem is detected on the primary cell and is not solved, a radio resource control (RRC) connection re-establishment procedure.

9. The terminal of claim 8, wherein the controller starts a timer if the random access problem is detected on the primary cell and executes, if the random access problem is not solved, the RRC connection re-establishment procedure.

10. The method of claim 9, wherein the controller stops the execution of the RRC connection re-establishment procedure upon expiration of the timer.

11. The terminal of claim 7, wherein the controller determines that the random access has failed if the number of transmissions of the random access preamble reaches to predetermined value.

12. The terminal of claim 7, wherein the random access problem is detected if a random access response is not received from the base station.