# US 11,115,829 B2 · Method and apparatus for performing channel sensing in a wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,115,829 B2 - Document ID: US11115829B2 - Status: Granted - Kind: B2 - Application number: 16/600,238 - Filed: 2019-10-11 - Published: 2020-02-06 - Granted: 2021-09-07 - Earliest claimed: 2015-03-23 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Hanjun Park; Joonkui Ahn; Seonwook Kim; Hyunho Lee - Web page: https://patentgrep.com/patent/US11115829B2 ## CPC - H04W 16/14: Spectrum sharing arrangements {between different networks} - H04B 17/318: Received signal strength - H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)} - H04W 74/0808: using carrier sensing, e.g. carrier sense multiple access [CSMA] - H04J 11/004: {using regenerative subtractive interference cancellation} - 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)} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract A method for transmitting a signal by a first apparatus in a wireless communication system, includes receiving a known signal, performing, on a carrier configured in an unlicensed band, a channel sensing based on cancelling a first value from power detected during a predetermined time interval related to the channel sensing and after the carrier is determined to be idle based on the channel sensing, transmitting, on the carrier, the signal, wherein the first value is determined based on reception power of the known signal and a cancellation ratio. ## Claims ### Claim 1 A method performed by a first apparatus in a wireless communication system, the method comprising: receiving a known signal; determining whether a channel available to be used for a plurality of radio technologies is occupied based on remaining power, wherein the remaining power is obtained based on cancelling a first value from power obtained on a time duration; and transmitting a signal on the channel based on the determination, wherein the time duration is determined based on the known signal, wherein the first value is determined based on reception power of the known signal and a cancellation ratio, and wherein the cancellation ratio is equal to or higher than 0 and equal to or less than 1. ### Claim 2 (depends on 1) The method of claim 1, further comprising: transmitting, to a second apparatus, information on a range of a transmission power of the signal; and receiving, from the second apparatus, a request to reduce the transmission power in response to the information on the range, wherein the transmission power is determined based on the request as a second value within the range to enable simultaneous transmission in the channel between the first apparatus and the second apparatus. ### Claim 3 (depends on 2) The method of claim 2, wherein the first apparatus and the second apparatus are included in a predetermined group of a plurality of apparatuses configured to allow simultaneous transmission in the channel. ### Claim 4 (depends on 3) The method of claim 3, wherein the known signal comprises a sequence obtained based on an identifier on identifying whether the second apparatus is included in the predetermined group, and wherein the transmission of the signal is performed based on the identifier identifying that the second apparatus is included in the predetermined group. ### Claim 5 A first apparatus configured to operate in a wireless communication system, the first apparatus comprising: a memory; and at least one processor coupled with the memory, wherein the at least one processor is configured to: receive a known signal; determine whether a channel available to be used for a plurality of radio technologies is occupied based on remaining power, wherein the remaining power is obtained based on cancelling a first value from power obtained on a time duration; and transmit a signal on the channel based on the determination, wherein the time duration is determined based on the known signal, wherein the first value is determined based on reception power of the known signal and a cancellation ratio, and wherein the cancellation ratio is equal to or higher than 0 and equal to or less than 1. ### Claim 6 (depends on 5) The first apparatus of claim 5, wherein the at least one processor is further configured to: transmit, to a second apparatus, information on a range of a transmission power of the signal; and receive, from the second apparatus, a request to reduce the transmission power in response to the information on the range, wherein the transmission power is determined based on the request as a second value within the range to enable simultaneous transmission in the channel between the first apparatus and the second apparatus. ### Claim 7 (depends on 6) The first apparatus of claim 6, wherein the first apparatus and the second apparatus are included in a predetermined group of a plurality of apparatuses configured to allow simultaneous transmission in the channel. ### Claim 8 (depends on 7) The first apparatus of claim 7, wherein the known signal comprises a sequence obtained based on an identifier on identifying whether the second apparatus is included in the predetermined group, and wherein the transmission of the signal is performed based on the identifier identifying that the second apparatus is included in the predetermined group. ### Claim 9 (depends on 1) The method of claim 1, wherein the channel is configured in an unlicensed band. ### Claim 10 (depends on 5) The first apparatus of claim 5, wherein the channel is configured in an unlicensed band.