Method and apparatus for performing random access procedure

• US 10,716,149 B2
• Filed: 01/26/2017
• Issued: 07/14/2020
• Est. Priority Date: 01/29/2016
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Ahn, Joonkui, Kim, Kijun, Kim, Byounghoon, Yang, Suckchel, Park, Hanjun, Yi, Yunjung, Kim, Seonwook
• Primary Examiner(s): Phan, Man U
• Application Number:
  US16/073,449
• Publication Number:
  US 20190037607A1
• Time in Patent Office: 1,265 Days
• Field of Search: 370329
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

Provided are a method of performing a random access procedure in an unlicensed band and a device using the method. The device performs a clear channel assessment (CCA) during a random access preamble (RAP) window in the unlicensed band. If the CCA succeeds, the wireless device transmits a plurality of RAPs. The plurality of RAPs are repeatedly transmitted in a frequency domain or a time domain.

Claims

1. A method for performing a random access procedure in an unlicensed band, the method comprising:

performing, by a wireless device, a clear channel assessment (CCA) during a random access preamble (RAP) window in the unlicensed band; and

transmitting, by the wireless device, a plurality of RAPs if the CCA is successful,

wherein the plurality of RAPs are repeatedly transmitted in a frequency domain or a time domain, and

wherein the plurality of RAPs include a first RAP transmitted in a first frequency band within the unlicensed band and a second RAP transmitted in a second frequency band within the unlicensed band, and the first RAP and the second RAP are transmitted at a same time point.

2. The method of claim 1, wherein a bandwidth at which the plurality of RAPs are transmitted occupies more than half of an entire bandwidth of the unlicensed band.

3. The method of claim 1, wherein the plurality of RAPs include a third RAP transmitted at a first time point within the unlicensed band and a fourth RAP transmitted at a second time point within the unlicensed band.

4. The method of claim 3, wherein the third RAP and the fourth RAP are transmitted in different frequency bands.

5. The method of claim 3, wherein a guard time is disposed between a last part of the third RAP and a start part of the fourth RAP.

6. The method of claim 1, wherein the plurality of RAPs include different RAP sequences.

7. The method of claim 1, further comprising

receiving, by the wireless device, a RAP order instructing a transmission of the plurality of RAPs,

wherein the RAP order includes information regarding a timing advance (TA) value to be applied to the transmission of the plurality of RAPs.

8. A device for performing a random access procedure in an unlicensed band, the device comprising:

a transceiver that transmits and receives a radio signal; and

a processor that;

performs a clear channel assessment (CCA) during a random access preamble (RAP) window in the unlicensed band; and

controls the transceiver to transmit a plurality of RAPs if the CCA is successful,

wherein the plurality of RAPs are repeatedly transmitted in a frequency domain or a time domain, and

wherein the plurality of RAPs include a first RAP transmitted in a first frequency band within the unlicensed band and a second RAP transmitted in a second frequency band within the unlicensed band, and the first RAP and the second RAP are transmitted at a same time point.

9. The device of claim 8, wherein a bandwidth at which the plurality of RAPs are transmitted occupies more than half of an entire bandwidth of the unlicensed band.

10. The device of claim 8, wherein the plurality of RAPs include a third RAP transmitted at a first time point within the unlicensed band and a fourth RAP transmitted at a second time point within the unlicensed band.

11. The device of claim 10, wherein the third RAP and the fourth RAP are transmitted in different frequency bands.

12. The device of claim 10, wherein a guard time is disposed between a last part of the third RAP and a start part of the fourth RAP.