Method and apparatus for performing channel sensing in a wireless communication system

Patent metadata

Field	Value
Publication number	US-2016286579-A1
Application number	US-201615077353-A
Country	US
Kind code	A1
Filing date	Mar 22, 2016
Priority date	Mar 23, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

Provided is a method for performing channel sensing in an unlicensed band in a wireless communication system, performed by a node performing channel sensing, the method comprising: receiving information about a known signal to be transmitted by at least one node of a group to which the node performing the channel sensing belongs to; detecting the known signal using the information about the known signal; canceling reception power of the known signal from measured reception power, during a time period in which the known signal is detected; comparing remaining reception power except for the reception power of the known signal with a threshold; and determining whether a channel is occupied or unoccupied according to a result of the comparison, wherein the information about the known signal includes at least one of a sequence of the known signal, transmission power of the known signal, a valid duration of the reception power of the known signal, a power offset between a transmission signal and the known signal during the valid duration, or a cancelation ratio of reception power of the transmission signal during the valid duration.

First claim

What is claimed is:

1 . A method for performing channel sensing in an unlicensed band in a wireless communication system, performed by a node performing channel sensing, the method comprising:
receiving information about a known signal to be transmitted by at least one node of a group to which the node performing the channel sensing belongs to; detecting the known signal using the information about the known signal; canceling reception power of the known signal from measured reception power, during a time period in which the known signal is detected; comparing remaining reception power except for the reception power of the known signal with a threshold; and determining whether a channel is occupied or unoccupied according to a result of the comparison, wherein the information about the known signal includes at least one of a sequence of the known signal, transmission power of the known signal, a valid duration of the reception power of the known signal, a power offset between a transmission signal and the known signal during the valid duration, or a cancelation ratio of reception power of the transmission signal during the valid duration.

2 . The method according to claim 1 , wherein the valid duration includes a subframe in which the known signal is detected or a subframe in which a signal of which reception power is to be derived from the reception power of the known signal is transmitted.

3 . The method according to claim 1 , wherein the known signal includes a reservation signal or a preamble to be transmitted for channel occupation after channel sensing is successful and before transmitting a signal during a channel occupancy time, or a reference signal for channel estimation and demodulation.

4 . The method according to claim 1 , further comprising, if the information about the known signal includes information about the valid duration or the known signal indicates the valid duration, canceling the reception power of the known signal from measured reception power during the valid duration.

5 . The method according to claim 1 , wherein if the known signal is transmitted in a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the known signal is transmitted with a predetermined phase difference in different OFDM symbols to indicate remaining lengths of a transmission burst including the known signal.

6 . The method according to claim 5 , further comprising using the reception power of the known signal in calculating reception power for the channel sensing during a time period corresponding to the remaining length of the transmission burst.

7 . A node for performing channel sensing in an unlicensed band in a wireless communication system, the node comprising:
a radio frequency (RF) unit; and a processor configured to control the RF unit, wherein the processor is configured to receive information about a known signal to be transmitted by at least one node of a group which the node performing the channel sensing belongs to, detect the known signal using the information about the known signal, cancel reception power of the known signal from measured reception power, during a time period in which the known signal is detected, compare remaining reception power except for the reception power of the known signal with a threshold, and determine whether a channel is occupied or unoccupied according to a result of the comparison, and wherein the information about the known signal includes at least one of a sequence of the known signal, transmission power of the known signal, a valid duration of the reception power of the known signal, a power offset between a transmission signal and the known signal during the valid duration, or a cancelation ratio of reception power of the transmission signal during the valid duration.

8 . The node according to claim 7 , wherein the valid duration includes a subframe in which the known signal is detected or a subframe in which a signal of reception power to be derived from the reception power of the known signal is transmitted.

9 . The node according to claim 7 , wherein the known signal includes a reservation signal or a preamble to be transmitted for channel occupation after channel sensing is successful and before a signal is transmitted during a channel occupancy time, or a reference signal for channel estimation and demodulation.

10 . The node according to claim 7 , wherein if the information about the known signal includes information about the valid duration or the known signal indicates the valid duration, the processor is configured to cancel the reception power of the known signal from measured reception power during the valid duration.

11 . The node according to claim 7 , wherein if the known signal is transmitted in a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the known signal is transmitted with a predetermined phase difference in different OFDM symbols to indicate remaining lengths of a transmission burst including the known signal.

12 . The node according to claim 11 , wherein the processor is configured to use the reception power of the known signal in calculating reception power for the channel sensing during a time period corresponding to the remaining length of the transmission burst.

Assignees

• Lg Electronics Inc

Inventors

• Park Hanjun
• Ahn Joonkui
• Kim Seonwook
• Lee Hyunho

Classifications

• H04J11/004

  using regenerative subtractive interference cancellation · CPC title

• H04W74/0808 Primary

  using carrier sensing, e.g. carrier sense multiple access [CSMA] · CPC title

• H04L27/0006

  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 title

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04W16/14 Primary

  Spectrum sharing arrangements {between different networks} · CPC title