# US 2019/0174546 A1 · Devices and methods for elaa multi-carrier lbt > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174546 A1 - Document ID: US20190174546A1 - Status: Published application - Kind: A1 - Application number: 16/321,812 - Filed: 2017-05-10 - Published: 2019-06-06 - Earliest claimed: 2016-08-22 - Assignees: Intel IP Corporation - Applicants: Intel IP Corporation - Inventors: Jeongho Jeon; Abhijeet Bhorhar; Seunghee Han; Hawan-Joon Kwon - Web page: https://patentgrep.com/patent/US20190174546A1 ## CPC - H04W 74/0816: with collision avoidance - H04W 74/006: {in the downlink, i.e. towards the terminal} - H04L 1/1812: Hybrid protocols; Hybrid automatic repeat request [HARQ] - H04W 74/0808: using carrier sensing, e.g. carrier sense multiple access [CSMA] - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Devices, methods, user equipment (UE), evolved node B (eNB), and storage media are described suitable for coexistence operations for uplink communications on multiple unlicensed carriers. Various embodiments are implemented in LTE systems with license-assisted access (LAA) associated communications. In one embodiment, a UE processes one or more uplink grants from an eNB scheduling transmissions on multiple unlicensed carriers at a first time, and indicating a first channel access procedure. The UE then selects a first unlicensed carrier and performs the first channel access procedure, and performs a second channel access procedure on a second unlicensed carrier of the multiple unlicensed carriers. ## Claims ### Claim 1 An apparatus of a user equipment for uplink channel access in license-assisted access (LAA), the apparatus comprising: a memory; and processing circuitry coupled to the memory and configured to: process one or more uplink (UL) grants from an evolved node B (eNB) scheduling a plurality of physical uplink shared channel (PUSCH) transmissions on a plurality of unlicensed carriers at a first PUSCH starting position, the one or more UL grants indicating a first channel access procedure for the plurality of PUSCH transmissions; select a first unlicensed carrier of the plurality of unlicensed carriers for the first channel access procedure associated with the first PUSCH starting position; and select at least a second unlicensed carrier of the plurality of unlicensed carriers other than the first unlicensed carrier for a second channel access procedure associated with the first PUSCH starting position. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein the memory is configured to store one or more channel access indications from the one or more uplink (UL) grants from the eNB scheduling the plurality of PUSCH transmissions on the plurality of unlicensed carriers at the first PUSCH starting position. ### Claim 3 (depends on 1) The apparatus of claim 1 wherein the first channel access procedure comprises a category-4 listen-before-talk (LBT) procedure. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein the first channel access procedure comprises a random backoff counter. ### Claim 5 (depends on 1) The apparatus of claim 1 wherein the second channel access procedure comprises a fixed LBT sensing interval. ### Claim 6 (depends on 5) The apparatus of claim 5 wherein the fixed LBT sensing interval is set to 25 microseconds. ### Claim 7 (depends on 1) The apparatus of claim 1 wherein the processing circuitry is further configured to initiate a first PUSCH transmission on the first unlicensed carrier following successful completion of the first channel access procedure. ### Claim 8 (depends on 7) The apparatus of claim 7 wherein the processing circuitry is further configured to initiate an additional PUSCH transmission on each of the remaining unlicensed carriers of the plurality of unlicensed carriers that has succeeded with the second channel access procedure immediately before the first PUSCH transmission on the first unlicensed carrier. ### Claim 9 (depends on 2) The apparatus of claim 2 wherein the processing circuitry is configured to select the first unlicensed carrier randomly from the plurality of unlicensed carriers. ### Claim 10 (depends on 1) The apparatus of claim 1 wherein the apparatus comprises an integrated circuit, wherein the processing circuitry comprises baseband circuitry disposed in the integrated circuit, and wherein the integrated circuit further comprises the memory. ### Claim 11 (depends on 1) The apparatus of claim 1 further comprising: one or more antennas coupled to the processing circuitry via radio frequency front-end circuitry, wherein the one or more antennas are configured to transmit the plurality of PUSCH transmissions; application circuitry coupled to the processing circuitry; and a display coupled to the application circuitry. ### Claim 12 A computer-readable storage medium comprising instructions for license-assisted access (LAA) uplink communication operations that, when executed by processing circuitry of an apparatus, configure the apparatus to: process one or more uplink (UL) grants from an evolved node B (eNB) scheduling a plurality of physical uplink shared channel (PUSCH) transmissions on a plurality of unlicensed carriers at a first PUSCH starting position, the one or more UL grants indicating a first channel access procedure for the plurality of PUSCH transmissions; autonomously select a first unlicensed carrier of the plurality of unlicensed carriers for the first channel access procedure associated with the first PUSCH starting position; and select remaining unlicensed carriers of the plurality of unlicensed carriers other than the first unlicensed carrier for a second channel access procedure associated with the first PUSCH starting position. ### Claim 13 (depends on 12) The computer-readable storage medium of claim 12 wherein the first channel access procedure comprises a listen-before-talk (LBT) procedure associated with a variable contention window (CW) updated based on hybrid automatic repeat request (HARQ) feedback for all carriers of the plurality of unlicensed carriers. ### Claim 14 (depends on 12) The computer-readable storage medium of claim 12 wherein the first channel access procedure comprises a random backoff counter. ### Claim 15 (depends on 12) The computer-readable storage medium of claim 12 wherein the second channel access procedure comprises a fixed LBT sensing interval. ### Claim 16 (depends on 15) The computer-readable storage medium of claim 15 wherein the fixed LBT sensing interval is set to 25 microseconds. ### Claim 17 (depends on 12) The computer-readable storage medium of claim 12 wherein the instructions further configure the apparatus to: initiate a first PUSCH transmission on the first unlicensed carrier following successful completion of the first channel access procedure. ### Claim 18 (depends on 17) The computer-readable storage medium of claim 17 wherein the instructions further configure the apparatus to: initiate an additional PUSCH transmission on each of the remaining unlicensed carriers of the plurality of unlicensed carriers that has succeeded with the second channel access procedure immediately before the first PUSCH transmission on the first unlicensed carrier. ### Claim 19 (depends on 13) The computer-readable storage medium of claim 13 wherein the instructions further configure the apparatus to: select the first unlicensed carrier randomly from the plurality of unlicensed carriers. ### Claim 20 An apparatus of a user equipment (UE) configured to operate using a plurality of unlicensed carriers in a license-assisted access (LAA) system, the apparatus comprising: a communication interface configured to receive one or more channel access indications from one or more uplink (UL) grants from an evolved node B (eNB) scheduling a plurality of physical uplink shared channel (PUSCH) transmissions on the plurality of unlicensed carriers at a first PUSCH starting position; and processing circuitry coupled to the communication interface and configured to: process the one or more UL grants to identify the first PUSCH starting position for the plurality of PUSCH transmissions on the plurality of unlicensed carriers; process the one or more UL grants to identify a Type 1 channel access procedure for the plurality of PUSCH transmissions on the plurality of unlicensed carriers; select a first carrier of the plurality of unlicensed carriers; initiate the Type 1 channel access procedure on the first carrier in response to selection of the first carrier; initiate a first PUSCH transmission of the plurality of PUSCH transmissions on the first carrier of the plurality of unlicensed carriers in response to the Type 1 channel access procedure; and initiate Type 2 channel access procedures on one or more second carriers of the plurality of unlicensed carriers, wherein the one or more second carriers do not include the first carrier, and wherein the Type 2 channel access procedures are performed immediately before the first PUSCH transmission on the first carrier. ### Claim 21 (depends on 20) The apparatus of claim 20 wherein the Type 1 channel access procedure comprises a listen-before-talk (LBT) procedure associated with a variable contention window (CW) calculated independently for each carrier of the plurality of unlicensed carriers and a backup counter based on a largest CW of the variable CWs calculated for each carrier of the plurality of unlicensed carriers. ### Claim 22 (depends on 20) The apparatus of claim 20 wherein the Type 1 channel access procedure comprises a random backoff counter. ### Claim 23 (depends on 20) The apparatus of claim 20 wherein the Type 2 channel access procedure comprises a fixed LBT sensing interval. ### Claim 24 (depends on 23) The apparatus of claim 23 wherein the fixed LBT sensing interval is set to 25 microseconds. ### Claim 25 (depends on 20) The apparatus of claim 20 further comprising a memory coupled to the processing circuitry and configured to store the one or more channel access indications; and wherein the processing circuitry of the UE is configured to select the first carrier randomly from the plurality of unlicensed carriers.