# US 12,193,062 B2 · Reducing likelihood of RACH transmission blockages for NR-U operation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,193,062 B2 - Document ID: US12193062B2 - Status: Granted - Kind: B2 - Application number: 17/593,523 - Filed: 2020-05-15 - Published: 2022-09-29 - Granted: 2025-01-07 - Earliest claimed: 2020-05-15 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Hong He; Chunhai Yao; Chunxuan Ye; Dawei Zhang; Haitong Sun; Jie Cui; Oghenekome Oteri; Sigen Ye; Wei Zeng; Weidong Yang; Yang Tang; Yushu Zhang - Web page: https://patentgrep.com/patent/US12193062B2 ## CPC - H04L 1/0068: {by puncturing} - H04W 74/006: {in the downlink, i.e. towards the terminal} - H04W 74/0808: using carrier sensing, e.g. carrier sense multiple access [CSMA] - H04W 74/0833: Random access procedures, e.g. with 4-step access - 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 Disclosed are techniques for reducing likelihood of Random Access Channel (RACH) transmission blockages and thereby facilitate an initial access procedure for new radio (NR) unlicensed spectrum (NR-U) operation in a fifth generation (5G) wireless communication system including an NR node. In some embodiments, a parameter generated by a gNB and received by a UE indicates that, from among a set of consecutive RACH Occasions (ROs), a gap is available for performing a listen-before-talk (LBT) procedure before commencing a RACH transmission. ## Claims ### Claim 1 A method, performed by a user equipment (UE), of reducing likelihood of Random Access Channel (RACH) transmission blockages and thereby facilitate an initial access procedure for new radio (NR) unlicensed spectrum (NR-U) operation in a fifth generation (5G) wireless communication system including an NR node, the method comprising: receiving from the NR node a parameter indicating that, from among a set of consecutive RACH Occasions (ROs), a gap is available for performing a listen-before-talk (LBT) procedure before commencing a RACH transmission, in which the parameter includes a bitmask having a set of logical values corresponding to the set of consecutive ROs such that each logical value indicates whether a corresponding RO is valid or invalid for the RACH transmission; and processing the parameter to determine a temporal location of the gap. ### Claim 2 (depends on 1) The method of claim 1 in which the parameter includes a puncturing factor indicating a periodicity of a non-consecutive RO available for the RACH transmission. ### Claim 3 (depends on 2) The method of claim 2 in which the parameter includes an offset factor indicating an offset location of the non-consecutive RO within each period indicated by the puncturing factor. ### Claim 4 (depends on 1) The method of claim 1 in which the parameter indicates ROs at even-numbered RO positions are valid such that the gap is defined as odd-numbered RO positions. ### Claim 5 (depends on 1) The method of claim 1 in which the parameter indicates ROs at odd-numbered RO positions are valid such that the gap is defined as even-numbered RO positions. ### Claim 6 (depends on 1) The method of claim 1 further comprising receiving the parameter in a System Information Block 1 (SIB1). ### Claim 7 (depends on 1) The method of claim 1 in which the gap includes a punctured portion of symbols of a Physical Random Access Channel (PRACH) format. ### Claim 8 (depends on 7) The method of claim 7 in which the parameter indicates a number of symbols comprising the punctured portion. ### Claim 9 (depends on 7) The method of claim 7 in which the punctured portion is a portion of a first symbol. ### Claim 10 (depends on 7) The method of claim 7 in which the punctured portion is a portion of a last symbol. ### Claim 11 (depends on 7) The method of claim 7 in which the parameter indicates a number of symbols comprising the punctured portion. ### Claim 12 A non-transitory computer-readable storage medium for a user equipment (UE) configured to reduce likelihood of Random Access Channel (RACH) transmission blockages and thereby facilitate an initial access procedure for new radio (NR) unlicensed spectrum (NR-U) operation in a fifth generation (5G) wireless communication system including an NR node, the computer-readable storage medium including instructions that when executed by a computer, cause the computer to: receive from the NR node a parameter indicating that, from among a set of consecutive RACH Occasions (ROs), a gap is available for performing a listen-before-talk (LBT) procedure before commencing a RACH transmission, in which the parameter includes a bitmask having a set of logical values corresponding to the set of consecutive ROs such that each logical value indicates whether a corresponding RO is valid or invalid for the RACH transmission; and process the parameter to determine a temporal location of the gap. ### Claim 13 (depends on 12) The computer-readable storage medium of claim 12 in which the parameter includes a puncturing factor to indicate a periodicity of a non-consecutive RO available for the RACH transmission. ### Claim 14 (depends on 13) The computer-readable storage medium of claim 13 in which the parameter includes an offset factor to indicate an offset location of the non-consecutive RO within each period indicated by the puncturing factor. ### Claim 15 (depends on 12) The computer-readable storage medium of claim 12 in which the parameter indicates ROs at even-numbered RO positions are valid such that the gap is defined as odd-numbered RO positions. ### Claim 16 (depends on 12) The computer-readable storage medium of claim 12 in which the parameter indicates ROs at odd-numbered RO positions are valid such that the gap is defined as even-numbered RO positions. ### Claim 17 (depends on 12) The computer-readable storage medium of claim 12 wherein the instructions further configure the computer to receive the parameter in a System Information Block 1 (SIB1). ### Claim 18 (depends on 12) The computer-readable storage medium of claim 12 in which the gap includes a punctured portion of symbols of a Physical Random Access Channel (PRACH) format.