DEVICE AND METHOD FOR TRANSMITTING/RECEIVING SIGNAL IN WIRELESS COMMUNICATION SYSTEM SUPPORTING UNLICENSED BAND

• US 20180176890A1
• Filed: 05/09/2016
• Published: 06/21/2018
• Est. Priority Date: 05/07/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: MOON, Jung-Min, RYOO, Sun-Heui, PARK, Seung-Hoon, JUNG, Jung-Soo
• Granted Patent: US 11,006,390 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 1/203 Details of error rate determination, e.g. BER, FER or WER
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/365 Power headroom reporting
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]

Abstract

The present invention relates to a 5^th generation (5G) or pre-5G communication system to be provided for supporting a data transmission rate higher than that of a 4^th generation (4G) communication system such as long term evolution (LTE). According to the present invention, a method by which a transmission device transmits a signal is a wireless communication system supporting an unlicensed band comprises the steps of: detecting the need for controlling a clear channel assessment (CCA) threshold during the performance of a CCA process; and controlling the CCA threshold used in the CCA process.

Claims

1. A method of a transmitting device in a wireless communication system supporting an unlicensed band, the method comprising:

determining to control a clear channel assessment (CCA) threshold value while performing a CCA process; and

controlling the CCA threshold value used in the CCA process.

3. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if transmission delay which corresponds to a set time occurs while performing the CCA process.

4. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if a number of automatic repeat request (ARQ) acknowledgments (ACKs) for data transmitted through an unlicensed band during a set first time, or a number of ARQ non-acknowledgments (NACKs) for the data transmitted through the unlicensed band during the set first time is greater than or equal to, or less than or equal to a set first threshold value, or

determining to control the CCA threshold value if a number of hybrid automatic repeat request (HARQ) ACKs for data transmitted through an unlicensed band during a set second time, or a number of HARQ NACKs for the data transmitted through the unlicensed band during the set second time is greater than or equal to, or less than or equal to a set second threshold value.

5. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if throughput for data transmitted through a unlicensed band during a set first time is greater than or equal to, or less than or equal to a set threshold throughput, or

determining to control the CCA threshold value if average latency for data transmitted through a unlicensed band during a set second time is greater than or equal to, or less than or equal to a set threshold latency.

6. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if a number of CCA slots in a clear channel state among CCA processes performed in a unlicensed band during a set first time is greater than or equal to, or less than or equal to a set first threshold value, or

determining to control the CCA threshold value if a number of CCA slots in a busy channel state among CCA processes performed in the unlicensed band during a set second time is greater than or equal to, or less than or equal to a set second threshold value.

7. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if time during which the transmitting device occupies a unlicensed band during a set first time is longer than or equal to, or shorter than or equal to a set first threshold time, or

determining to control the CCA threshold value if time during which the transmitting device does not occupy a unlicensed band during a set second time is longer than or equal to, or shorter than or equal to a set second threshold time.

8. The method of claim 1, wherein determining to control the CCA threshold value while performing the CCA process comprises:

determining to control the CCA threshold value if average signal strength from at least one transmitting device measured in a unlicensed band during a set first time is greater than or equal to, or less than or equal to set threshold signal strength,

determining to control the CCA threshold value if an average buffer occupancy rate of a transmitting device measured in a unlicensed band during a set second time is greater than or equal to, or less than or equal to a set threshold buffer occupancy rate, or

determining to control the CCA threshold value upon receiving a predefined signal in a unlicensed band from other transmitting devices.

9. The method of claim 1, wherein controlling the CCA threshold value used in the CCA process comprises:

controlling the CCA threshold value such that a fixed CCA threshold value is used every CCA opportunity as an opportunity at which a CCA process is performable.

10. The method of claim 1, wherein controlling the CCA threshold value used in the CCA process comprises:

controlling the CCA threshold value such that a plurality of CCA threshold values are used every CCA opportunity as an opportunity at which a CCA process is performable.

11. The method of claim 1, wherein controlling the CCA threshold value used in the CCA process comprises:

controlling the CCA threshold value such that a CCA threshold value which is less than a CCA threshold value used at a current CCA opportunity is used at a next CCA opportunity, or controlling the CCA threshold value such that a CCA threshold value which is greater than the CCA threshold value used at the current CCA opportunity is used at the next CCA opportunity, and

wherein a CCA opportunity denotes an opportunity at which a CCA process is performable.

2. (canceled)

12-15. -15. (canceled)

16. A transmitting device in a wireless communication system, the transmitting device comprising:

a transceiver configured to transmit or receive a signal; and

at least one processor coupled with the transceiver and configured to;

determine to control a clear channel assessment (CCA) threshold value while performing a CCA process; and

control the CCA threshold value used in the CCA process.

17. The transmitting device of claim 16, wherein the at least one processor is configured to determine to control the CCA threshold value if transmission delay which corresponds to set time occurs while performing the CCA process.

18. The transmitting device of claim 16, wherein the at least one processor is configured to:

determine to control the CCA threshold value if a number of automatic repeat request (ARQ) acknowledgments (ACKs) for data transmitted through an unlicensed band during a set first time, or a number of ARQ non-acknowledgments (NACKs) for the data transmitted through the unlicensed band during the set first time is greater than or equal to, or less than or equal to a set first threshold value, or

determine to control the CCA threshold value if a number of hybrid automatic repeat request (HARQ) ACKs for data transmitted through an unlicensed band during a set second time, or a number of HARQ NACKs for the data transmitted through the unlicensed band during the set second time is greater than or equal to, or less than or equal to a set second threshold value.

19. The transmitting device of claim 16, wherein the at least one processor is configured to:

determine to control the CCA threshold value if throughput for data transmitted through a unlicensed band during a set first time is greater than or equal to, or less than or equal to a set threshold throughput, or

determine to control the CCA threshold value if average latency for data transmitted through a unlicensed band during a set second time is greater than or equal to, or less than or equal to a set threshold latency.

20. The transmitting device of claim 16, wherein the at least one processor is configured to:

determine to control the CCA threshold value if a number of CCA slots in a clear channel state among CCA processes performed in a unlicensed band during a set first time is greater than or equal to, or less than or equal to a set first threshold value, or

determine to control the CCA threshold value if a number of CCA slots in a busy channel state among CCA processes performed in the unlicensed band during a set second time is greater than or equal to, or less than or equal to a set second threshold value.

21. The transmitting device of claim 16, wherein the at least one processor is configured to:

determine to control the CCA threshold value if time during which the transmitting device occupies a unlicensed band during a set first time is longer than or equal to, or shorter than or equal to a set first threshold time, or

determine to control the CCA threshold value if time during which the transmitting device does not occupy a unlicensed band during a set second time is longer than or equal to, or shorter than or equal to a set second threshold time.

22. The transmitting device of claim 16, wherein the at least one processor is configured to:

determine to control the CCA threshold value if average signal strength from at least one transmitting device measured in a unlicensed band during a set first time is greater than or equal to, or less than or equal to a set threshold signal strength,

determine to control the CCA threshold value if an average buffer occupancy rate of a transmitting device measured in a unlicensed band during a set second time is greater than or equal to, or less than or equal to a set threshold buffer occupancy rate, or

determine to control the CCA threshold value upon receiving a predefined signal in a unlicensed band from other transmitting devices.

23. The transmitting device of claim 16, wherein the at least one processor is configured to control the CCA threshold value such that a fixed CCA threshold value is used every CCA opportunity as an opportunity at which a CCA process is performable.

24. The transmitting device of claim 16, wherein the at least one processor is configured to control the CCA threshold value such that a plurality of CCA threshold values are used every CCA opportunity as an opportunity at which a CCA process is performable.

25. The transmitting device of claim 16, wherein the at least one processor is configured to control the CCA threshold value such that a CCA threshold value which is less than a CCA threshold value used at a current CCA opportunity is used at a next CCA opportunity, or controlling the CCA threshold value such that a CCA threshold value which is greater than the CCA threshold value used at the current CCA opportunity is used at the next CCA opportunity, and

wherein a CCA opportunity denotes an opportunity at which a CCA process is performable.