METHOD FOR PERFORMING A RANDOM ACCESS PROCEDURE IN A CARRIER AGGREGATION WITH AT LEAST ONE SCELL OPERATING IN AN UNLICENSED SPECTRUM AND A DEVICE THEREFOR

• US 20180049243A1
• Filed: 04/06/2016
• Published: 02/15/2018
• Est. Priority Date: 04/10/2015
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: LEE, Sunyoung, YI, Seungjune
• Granted Patent: US 10,455,622 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

The present invention relates to a wireless communication system. More specifically, the present invention relates to a method and a device for performing a random access procedure in a carrier aggregation with at least one SCell operating in an unlicensed spectrum, the method comprising: configuring a timer; starting the timer when the UE initiates a Random Access Preamble (RAP) transmission procedure on a first cell; stopping the RAP transmission procedure on the first cell if a Random Access Response (RAR) for the RAP transmission procedure on the first cell is not received until the timer expires.

Claims

1. A method for a User Equipment (UE) operating in a wireless communication system, the method comprising:

configuring a timer;

starting the timer when the UE initiates a Random Access Preamble (RAP) transmission procedure on a first cell;

stopping the RAP transmission procedure on the first cell if a Random Access Response (RAR) for the RAP transmission procedure on the first cell is not received until the timer expires; and

transmitting an indication to an eNB indicating that the UE stops the RAP transmission procedure on the first cell through a second cell configured for the UE.

2. The method according to claim 1, wherein the RAP transmission includes that the UE transmits a RAP, monitors a RAR for the RAP during a RAR window, and retransmits the RAP if the RAR is not received during the RAR window.

4. The method according to claim 2, wherein the RAR for the RAP transmission procedure contains a RAP ID corresponding to the RAP the UE transmits.

5. The method according to claim 1, wherein the first cell is an unlicensed cell.

6. The method according to claim 1, wherein the UE initiates the RAP transmission procedure on the first cell when a PDCCH order is received from the eNB.

7. The method according to claim 1, wherein the timer is configured per a cell or a UE.

8. The method according to claim 2, wherein the timer stops, when the RAR containing a RAP ID corresponding to the RAP is received from the eNB, or a maximum number of RAP transmission is reached, or a random access procedure on the first cell is stopped by the UE, or another random access procedure on the first cell is started by the UE.

9. The method according to claim 1, wherein the indication includes an identification of the first cell on which the RAP transmission procedure is stopped, or an identification of the RAP of which the transmission on the first cell is stopped.

3. (canceled)

10. A method for a User Equipment (UE) operating in a wireless communication system, the method comprising:

initiating a Random Access Preamble (RAP) transmission procedure on a first cell;

stopping the RAP transmission procedure on the first cell when a certain condition is met; and

transmitting an indication to an eNB indicating that the UE stops the RAP transmission procedure on the first cell through a second cell configured for the UE when the RAP transmission procedure on the first cell is stopped.

11. The method according to claim 10, wherein the first cell is an unlicensed cell.

12. The method according to claim 10, wherein the second cell is a PCell, or a PSCell, or any cell among the cells on a licensed spectrum, or any cell among the cells on an unlicensed spectrum and not occupied by other transmitters.

13. The method according to claim 10, wherein the indication is transmitted via Physical layer (PHY), Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), or Radio Resource Control (RRC) signal.

14. The method according to claim 10, wherein the indication includes an identification of the first cell on which the RAP transmission procedure is stopped, or an identification of the RAP of which the transmission on the first cell is stopped.

15. The method according to claim 10, wherein the UE initiates the RAP transmission procedure on the first cell when a PDCCH order is received from the eNB.

16. A User Equipment (UE) operating in a wireless communication system, the UE comprising:

a Radio Frequency (RF) module; and

a processor operably coupled with the RF module and configured to;

initiate a Random Access Preamble (RAP) transmission procedure on a first cell;

stop the RAP transmission procedure on the first cell when a certain condition is met; and

transmit an indication to an eNB indicating that the UE stops the RAP transmission procedure on the first cell through a second cell configured for the UE when the RAP transmission procedure on the first cell is stopped.

17. The UE according to claim 16, wherein the first cell is an unlicensed cell.

18. The UE according to claim 16, wherein the second cell is a PCell, or a PSCell, or any cell among the cells on a licensed spectrum, or any cell among the cells on an unlicensed spectrum and not occupied by other transmitters.

19. The UE according to claim 16, wherein the indication includes an identification of the first cell on which the RAP transmission procedure is stopped, or an identification of the RAP of which the transmission on the first cell is stopped.

20. The UE according to claim 16, wherein the UE initiates the RAP transmission procedure on the first cell when a PDCCH order is received from the eNB.