# US 10,374,760 B2 · Method for transmitting data in unlicensed band-secondary carrier and device for same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,760 B2 - Document ID: US10374760B2 - Status: Granted - Kind: B2 - Application number: 15/520,405 - Filed: 2015-11-05 - Published: 2017-11-02 - Granted: 2019-08-06 - Earliest claimed: 2014-11-06 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Kijun Kim; Joonkui Ahn; Hanbyul Seo; Seonwook Kim - Web page: https://patentgrep.com/patent/US10374760B2 ## CPC - H04L 5/0012: {Hopping in multicarrier systems} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 5/001: {the frequencies being arranged in component carriers} - H04W 72/12: Wireless traffic scheduling - H04W 74/08: Non-scheduled access, e.g. ALOHA (hybrid access H04W74/02) - H04L 5/005: {of common pilots, i.e. pilots destined for multiple users or terminals} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract According to one embodiment of the present invention, a method by which a terminal transmits data in an unlicensed band-secondary carrier comprises the steps of: receiving, from a base station, a channel including scheduling information of the unlicensed band-secondary carrier in a primary carrier; and starting the transmission of a data train including a plurality of data units in the unlicensed band-secondary carrier when the scheduling information is received and the channel idles during a first sensing period, wherein a transmission period of the data unit is set to match a time interval of at least one downlink sub frame of the primary carrier, and the transmission period of the data unit can include a data transmission period and a second sensing period. ## Claims ### Claim 1 A method of transmitting data in an unlicensed band-secondary carrier, the method performed by a terminal and comprising: receiving, by the terminal, scheduling information to transmit data on the unlicensed band-secondary carrier from a base station on a primary carrier; and when the scheduling information is received, a channel state on the unlicensed band-secondary carrier is idle during a first sensing period T1, an amount of the data present in a buffer is equal to or greater than a predetermined amount, the data has a predetermined type, and the amount of the data is to be transmitted over a predetermined number of data units using an expected transmission modulation and coding scheme (MCS), starting a transmission of a data train including a plurality of data units 1 to M on the unlicensed band-secondary carrier, wherein the plurality of data units 1 to M are transmitted in consecutive transmission periods T(1) to T(M), respectively, wherein a transmission period T(m) for each of the plurality of data units 1 to M is configured to be matched with a time period of one or more downlink subframes of the primary carrier, wherein T(m) is a transmission period for a data unit m among the plurality of data units, and m=1, . . . , M, wherein T(m) consists of a data transmission period T3(m) and a second sensing period T2, and wherein T3(m) increases as m increases in the data train. ### Claim 2 (depends on 1) The method of claim 1, further comprising: when the channel state on the unlicensed band-secondary carrier is idle during the second sensing period T2 for a data unit n among the plurality of data units 1 to M, wherein n denotes an integer equal to or greater than 1, and less than M, transmitting a data unit n+1. ### Claim 3 (depends on 2) The method of claim 2, further comprising: when the terminal succeeds in transmitting consecutive data units in transmission periods for the consecutive data units: increasing, by the terminal, a counter value by 1; and determining, by the terminal, whether or not the counter value reaches a maximum value, wherein when the counter value reaches the maximum value, a data unit is not transmitted in a transmission period for a next data unit irrespective of whether the channel state on the unlicensed band-secondary carrier is idle or not during the second sensing period T2. ### Claim 4 (depends on 3) The method of claim 3, wherein when the channel state on the unlicensed band-secondary carrier is busy during the second sensing period T2, the counter value is initialized. ### Claim 5 (depends on 1) The method of claim 1, further comprising: when it is determined that the channel state on the unlicensed band-secondary carrier is idle during the first sensing period T1 and a terminal-specific backoff time followed by the first sensing period T1 after the transmission of the data train is completed, starting, by the terminal, a transmission of a next data train. ### Claim 6 (depends on 1) The method of claim 1, wherein the first sensing period T1 is longer than the second sensing period T2. ### Claim 7 (depends on 1) The method of claim 1, further comprising: receiving, by the terminal from the base station, configuration information on a muted subframe of the unlicensed band-secondary carrier in which the transmission of the data train of the terminal is not performed regardless of whether the channel state on the unlicensed band-secondary carrier is idle or not, wherein the configuration information on the muted subframe comprises a period and an offset for the muted subframe. ### Claim 8 (depends on 7) The method of claim 7, wherein the period and the offset for the muted subframe are determined by a function of a physical layer cell identifier of the base station. ### Claim 9 A terminal configured to transmit data in an unlicensed band-secondary carrier, comprising: a radio frequency (RF) unit; and a processor configured to: control the RF unit; receive scheduling information to transmit data on the unlicensed band-secondary carrier from a base station on a primary carrier; and when the scheduling information is received, a channel state on the unlicensed band-secondary carrier is idle during a first sensing period T1, an amount of the data present in a buffer is equal to or greater than a predetermined amount, the data has a predetermined type, and the amount of the data is to be transmitted over a predetermined number of data units using an expected transmission modulation and coding scheme (MCS), start a transmission of a data train including a plurality of data units 1 to M on the unlicensed band-secondary carrier, wherein the plurality of data units 1 to M are transmitted in consecutive transmission periods T(1) to T(M), respectively, wherein a transmission period T(m) for each of the plurality of data units 1 to M is configured to be matched with a time period of one or more downlink subframes of the primary carrier, wherein T(m) is a transmission period for a data unit m among the plurality of data units, and m=1, . . . , M, wherein T(m) consists of a data transmission period T3(m) and a second sensing period T2, and wherein T3(m) increases as m increases in the data train. ### Claim 10 (depends on 9) The terminal of claim 9, wherein when the channel state on the unlicensed band-secondary carrier is idle during the second sensing period T2 for a data unit n among the plurality of data units 1 to M, wherein n denotes an integer equal to or greater than 1, and less than M, the processor controls the RF unit to transmit a data unit n+1. ### Claim 11 (depends on 10) The terminal of claim 10, wherein when the terminal succeeds in transmitting consecutive data units in transmission periods for the consecutive data units, the processor increases a counter value by 1, and determines whether or not the counter value reaches a maximum value, and wherein when the counter value reaches the maximum value, a data unit is not transmitted in a transmission period for a next data unit irrespective of whether the channel state on the unlicensed band-secondary carrier is idle or not during the second sensing period T2. ### Claim 12 (depends on 11) The terminal of claim 11, wherein when the channel state on the unlicensed band-secondary carrier is busy during the second sensing period T2, the counter value is initialized. ### Claim 13 (depends on 9) The terminal of claim 9, wherein when it is determined that the channel state on the unlicensed band-secondary carrier is idle during the first sensing period T1 and a terminal-specific backoff time followed by the first sensing period T1 after the transmission of the data train is completed, the processor starts a transmission of a next data train. ### Claim 14 (depends on 9) The terminal of claim 9, wherein the first sensing period T1 is longer than the second sensing period T2. ### Claim 15 (depends on 9) The terminal of claim 9, wherein the processor further controls the RF unit to receive, from the base station, configuration information on a muted subframe of the unlicensed band-secondary carrier in which the transmission of the data train of the terminal is not performed regardless of whether the channel state on the unlicensed band-secondary carrier is idle or not, wherein the configuration information on the muted subframe comprises a period and an offset for the muted subframe. ### Claim 16 (depends on 15) The terminal of claim 15, wherein the period and the offset for the muted subframe are determined by a function of a physical layer cell identifier of the base station.