# US 11,310,837 B2 · Network access node and a client device for generating and using randoms access sequences > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,837 B2 - Document ID: US11310837B2 - Status: Granted - Kind: B2 - Application number: 16/950,159 - Filed: 2020-11-17 - Published: 2021-03-11 - Granted: 2022-04-19 - Earliest claimed: 2018-05-23 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Renaud-Alexandre Pitaval; Branislav M. Popovic - Web page: https://patentgrep.com/patent/US11310837B2 ## CPC - H04J 13/0062: {Zadoff-Chu} - H04J 13/14: Generation of codes with a zero correlation zone - H04L 27/2607: {Cyclic extensions} - H04L 27/2613: {Structure of the reference signals} - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 27/2614: {Peak power aspects} - H04W 74/0833: Random access procedures, e.g. with 4-step access - 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) - 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 A network access node and a client device for generating and using cubic phase polynomial sequences (si, sj) of length L with a third order coefficient value a3 belonging to the subset of sequences () are described. The network access node transmits a control message to the client device, wherein the control message indicates the cyclical shift value NCS and the third order coefficient value a3. The client device receives the control message and determines a cubic polynomial phase sequence (si) belonging to the subset of sequences () based on the cyclical shift value NCS and the third order coefficient value a3. The client device thereafter transmits the determined cubic polynomial phase sequence (si) as a random access preamble to the network access node. ## Claims ### Claim 1 An apparatus, comprising: at least one processor; a memory coupled to the at least one processor, wherein the memory stores a program to be executed by the at least one processor, and wherein the program comprises instructions which, when executed by the at least one processor, instruct the at least one processor to perform operations comprising: generating a subset of sequences (k) belonging to a set of sequences (), wherein: the subset of sequences (k) comprises a plurality of cubic phase polynomial sequences (si, sj) of length L with a third order coefficient value a3; an auto-correlation for a sequence (si) in the generated subset of sequences with a cyclically shifted version of itself (s′i) is less than or equal to √{square root over (L)} when the cyclically shifted version (s′i) is cyclically shifted less than a cyclical shift value NCS; a cross-correlation between a first sequence (si) and a second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)}; and a cross-correlation between the first sequence (si) and the second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)} when one of the first sequence (si) and the second sequence (sj) is cyclically shifted less than the cyclical shift value NCS; and transmitting a control message to a client device, wherein the control message indicates the cyclical shift value NCS and the third order coefficient value a3. ### Claim 2 (depends on 1) The apparatus according to claim 1, wherein a cross-correlation between two sequences belonging to two different subsets of sequences is less than or equal to 2√{square root over (L)}. ### Claim 3 (depends on 1) The apparatus according to claim 1, wherein third order coefficients of sequences belonging to different subsets of sequences are different. ### Claim 4 (depends on 1) The apparatus according to claim 1, wherein each sequence belonging to the set of sequences () has a non-zero third order coefficient value a3. ### Claim 5 (depends on 1) The apparatus according to claim 1, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of a Zadoff-Chu sequence with an Alltop sequence. ### Claim 6 (depends on 5) The apparatus according to claim 5, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of the Zadoff-Chu sequence cyclically shifted by a multiple of the cyclical shift value NCS with any cyclically-shifted version of the Alltop sequence. ### Claim 7 (depends on 5) The apparatus according to claim 5, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of any cyclically shifted version of the Zadoff-Chu sequence with the Alltop sequence cyclically shifted by a multiple of the cyclical shift value NCS. ### Claim 8 (depends on 1) The apparatus according to claim 1, wherein a second order coefficient value a2 is a product of the third order coefficient value a3 and the cyclical shift value NCS. ### Claim 9 An apparatus, comprising: at least one processor; a memory coupled to the at least one processor, wherein the memory stores a program to be executed by the at least one processor, and wherein the program comprises instructions which, when executed by the at least one processor, instruct the at least one processor to perform operations comprising: receiving a control message from a network access node, wherein the control message indicates a cyclical shift value NCS and a third order coefficient value a3 of a subset of sequences (k); determining a cubic polynomial phase sequence (si) belonging to the subset of sequences (k) based on the cyclical shift value NCS and the third order coefficient value a3; transmitting the determined cubic polynomial phase sequence (si) as a random access preamble to the network access node. ### Claim 10 (depends on 9) The apparatus according to claim 9, wherein determining the cubic polynomial phase sequence comprises: determining a first order coefficient value a1 based on the third order coefficient value a3 and the cyclical shift value NCS; and determining a second order coefficient value a2 based on the third order coefficient value a3. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein determining the cubic polynomial phase sequence comprises: determining a first order coefficient value a1 as an arbitrary value; and determining a second order coefficient value a2 based on the third order coefficient value a3 and the cyclical shift value NCS. ### Claim 12 (depends on 9) The apparatus according to claim 9, wherein the subset of sequences (k) is a subset belonging to a set of sequences (), wherein: the subset of sequences (k) comprises a plurality of cubic phase polynomial sequences (si, sj, . . . ) of length L with a third order coefficient value a3; an auto-correlation for a sequence (si) in the generated subset of sequences with a cyclically shifted version of itself (s′i) is less than or equal to √{square root over (L)} when the cyclically shifted version (s′i) is cyclically shifted less than a cyclical shift value NCS; a cross-correlation between a first sequence (si) and a second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)}; and a cross-correlation between the first sequence (k) and the second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)} when one of the first sequence (si) and the second sequence (sj) is cyclically shifted less than the cyclical shift value NCS. ### Claim 13 A method, comprising: generating a subset of sequences (k) belonging to a set of sequences (), wherein: the subset of sequences (k) comprises a plurality of cubic phase polynomial sequences (si, sj) of length L with a third order coefficient value a3; an auto-correlation for a sequence (si) in the generated subset of sequences with a cyclically shifted version of itself (s′i) is less than or equal to √{square root over (L)} when the cyclically shifted version (s′i) is cyclically shifted less than a cyclical shift value NCS; a cross-correlation between a first sequence (si) and a second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)}; and a cross-correlation between the first sequence (si) and the second sequence (sj) in the generated subset of sequences (k) is less than or equal to √{square root over (L)} when one of the first sequence (si) and the second sequence (sj) is cyclically shifted less than the cyclical shift value NCS; and transmitting a control message to a client device, wherein the control message indicates the cyclical shift value NCS and the third order coefficient value a3. ### Claim 14 (depends on 13) The method according to claim 13, wherein a cross-correlation between two sequences belonging to two different subsets of sequences is less than or equal to 2√{square root over (L)}. ### Claim 15 (depends on 13) The method according to claim 13, wherein third order coefficients of sequences belonging to different subsets of sequences are different. ### Claim 16 (depends on 13) The method according to claim 13, wherein each sequence belonging to the set of sequences () has a non-zero third order coefficient value a3. ### Claim 17 (depends on 13) The method according to claim 13, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of a Zadoff-Chu sequence with an Alltop sequence. ### Claim 18 (depends on 17) The method according to claim 17, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of the Zadoff-Chu sequence cyclically shifted by a multiple of the cyclical shift value NCS with any cyclically-shifted version of the Alltop sequence. ### Claim 19 (depends on 17) The method according to claim 17, wherein generating the subset of sequences (k) comprises: element-by-element multiplication of any cyclically shifted version of the Zadoff-Chu sequence with the Alltop sequence cyclically shifted by a multiple of the cyclical shift value NCS. ### Claim 20 (depends on 13) The method according to claim 13, wherein a second order coefficient value a2 is a product of the third order coefficient value a3 times the cyclical shift value NCS.