# US 12,010,640 B2 · Method for transmitting/receiving synchronization signal for D2D communication in wireless communication system, and apparatus therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,010,640 B2 - Document ID: US12010640B2 - Status: Granted - Kind: B2 - Application number: 18/152,692 - Filed: 2023-01-10 - Published: 2023-05-25 - Granted: 2024-06-11 - Earliest claimed: 2014-02-13 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Hakseong Kim; Inkwon Seo; Hanbyul Seo; Daewon Seo; Youngtae Kim; Hyukjin Chae - Web page: https://patentgrep.com/patent/US12010640B2 ## CPC - H04W 56/0015: {one node acting as a reference for the others} - 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)} - 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} - H04L 27/26035: {Maintenance of orthogonality, e.g. for signals exchanged between cells or users, or by using covering codes or sequences (using different training sequence per antenna H04B7/0684; code allocation H04J13/16)} - H04L 27/2613: {Structure of the reference signals} - H04L 27/2692: {with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver} - H04W 76/14: Direct-mode setup - 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 The present invention relates to a method and an apparatus which enable a terminal to transmit a signal for device-to-device (D2D) communication in a wireless communication system. Specifically, the present invention transmits a synchronization signal for D2D communication and a demodulation reference signal (DM-RS) for demodulation of the synchronization signal, wherein the base sequence of the demodulation reference signal is generated using a synchronization reference ID. ## Claims ### Claim 1 A method of transmitting a signal by a user equipment (UE) via a communication between the UE and another UE, the method comprising: generating a plurality of bits for a physical channel including synchronization related information for the communication; generating a demodulation reference signal (DM-RS) related to the physical channel, based on an orthogonal code, a cyclic shift, and a sequence; and transmitting the physical channel and the DM-RS to the other UE, wherein each of the orthogonal code, the cyclic shift, and the sequence is determined based on a synchronization identity for the communication. ### Claim 2 (depends on 1) The method according to claim 1, wherein the plurality of bits for the physical channel is scrambled based on the synchronization identity. ### Claim 3 (depends on 1) The method according to claim 1, wherein the physical channel is a physical broadcast channel for the communication. ### Claim 4 (depends on 1) The method according to claim 1, wherein the orthogonal code is determined based on a first part related with some lower bits of the synchronization identity, wherein the cyclic shift is determined based on a second part of the synchronization identity, which is related with remaining lower bits except for the first part among bits of the synchronization identity, and wherein the sequence is determined based on a third part related with remaining bits except for the first and second parts among the bits of the synchronization identity. ### Claim 5 (depends on 4) The method according to claim 4, wherein the first part is one least significant bit of the synchronization identity, and wherein the second part is remaining three lower bits except for the one least significant bit among four lower bits of the synchronization identity. ### Claim 6 (depends on 1) The method according to claim 1, wherein the orthogonal code is determined based on a modulo 2 operation performed upon the synchronization identity, and wherein the cyclic shift is determined by applying a modulo 8 operation to a floor function of a value obtained by dividing the synchronization identity by 2. ### Claim 7 A device for a user equipment (UE) in a communication between the UE and another UE, the device comprising: at least one processor; and at least one memory storing instructions that, when executed, cause the at least one processor to perform operations comprising: generating a plurality of bits for a physical channel including synchronization related information for the communication; generating a demodulation reference signal (DM-RS) related to the physical channel, based on an orthogonal code, a cyclic shift, and a sequence; and transmitting the physical channel and the DM-RS to the other UE, wherein each of the orthogonal code, the cyclic shift, and the sequence is determined based on a synchronization identity for the communication. ### Claim 8 (depends on 7) The device according to claim 7, wherein the plurality of bits for the physical channel is scrambled based on the synchronization identity. ### Claim 9 (depends on 7) The device according to claim 7, wherein the physical channel is a physical broadcast channel for the communication. ### Claim 10 (depends on 7) The device according to claim 7, wherein the orthogonal code is determined based on a first part related with some lower bits of the synchronization identity, wherein the cyclic shift is determined based on a second part of the synchronization identity, which is related with remaining lower bits except for the first part among bits of the synchronization identity, and wherein the sequence is determined based on a third part related with remaining bits except for the first and second parts among the bits of the synchronization identity. ### Claim 11 (depends on 10) The device according to claim 10, wherein the first part is one least significant bit of the synchronization identity, and wherein the second part is remaining three lower bits except for the one least significant bit among four lower bits of the synchronization identity. ### Claim 12 (depends on 7) The device according to claim 7, wherein the orthogonal code is determined based on a modulo 2 operation performed upon the synchronization identity, and wherein the cyclic shift is determined by applying a modulo 8 operation to a floor function of a value obtained by dividing the synchronization identity by 2. ### Claim 13 A computer-readable non-transitory storage medium storing instructions that, when executed, cause at least one processor for a user equipment (UE) to perform operations for communication between the UE and another UE, the operations comprising: generating a plurality of bits for a physical channel including synchronization related information for the communication; generating a demodulation reference signal (DM-RS) related to the physical channel, based on an orthogonal code, a cyclic shift, and a sequence; and transmitting the physical channel and the DM-RS to the other UE, wherein each of the orthogonal code, the cyclic shift, and the sequence is determined based on a synchronization identity for the communication. ### Claim 14 (depends on 13) The computer-readable non-transitory storage medium according to claim 13, wherein the plurality of bits for the physical channel is scrambled based on the synchronization identity. ### Claim 15 (depends on 13) The computer-readable non-transitory storage medium according to claim 13, wherein the physical channel is a physical broadcast channel for the communication. ### Claim 16 (depends on 13) The computer-readable non-transitory storage medium according to claim 13, wherein the orthogonal code is determined based on a first part related with some lower bits of the synchronization identity, wherein the cyclic shift is determined based on a second part of the synchronization identity, which is related with remaining lower bits except for the first part among bits of the synchronization identity, and wherein the sequence is determined based on a third part related with remaining bits except for the first and second parts among the bits of the synchronization identity. ### Claim 17 (depends on 16) The computer-readable non-transitory storage medium according to claim 16, wherein the first part is one least significant bit of the synchronization identity, and wherein the second part is remaining three lower bits except for the one least significant bit among four lower bits of the synchronization identity. ### Claim 18 (depends on 13) The computer-readable non-transitory storage medium according to claim 13, wherein the orthogonal code is determined based on a modulo 2 operation performed upon the synchronization identity, and wherein the cyclic shift is determined by applying a modulo 8 operation to a floor function of a value obtained by dividing the synchronization identity by 2.