# US 11,121,748 B2 · Synchronizing devices in a wireless communication network > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,121,748 B2 - Document ID: US11121748B2 - Status: Granted - Kind: B2 - Application number: 16/346,480 - Filed: 2017-11-03 - Published: 2019-09-12 - Granted: 2021-09-14 - Earliest claimed: 2016-11-04 - Assignees: Sony Group Corporation - Applicants: Sony Mobile Communications Inc. - Inventors: Erik Bengtsson; Basuki Priyanto; Olof Zander - Web page: https://patentgrep.com/patent/US11121748B2 ## CPC - H04B 7/0456: Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting - H04B 7/0617: {for beam forming} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04W 56/0005: {synchronizing of arrival of multiple uplinks} - H04W 56/001: {Synchronization between nodes} - H04W 72/0473: {the resource being transmission power} - H04W 72/535: {based on resource usage policies} - H04B: TRANSMISSION - 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 The present disclosure relates to a method for operating a base station of a wireless communication network. Precoding information for concentrating a radio-frequency power of a transmitted radio-frequency signal to a group of terminal devices arranged in a sub area of a coverage area of the base station is determined and applied to an antenna array of the base station. A synchronization signal is transmitted from the base station to the group of terminal devices using the precoding information. ## Claims ### Claim 1 A method for operating a base station of a wireless communication network, the base station comprising an antenna array having a plurality of antennas configured to communicate wirelessly with terminal devices positioned within a coverage area of the base station, a spatial transmission characteristic of the antenna array being configurable by applying precoding information, the method comprising: determining the precoding information for concentrating a radio frequency power of a transmitted radio frequency signal to a group of terminal devices arranged in a sub area of the coverage area of the base station, applying the determined precoding information to the antenna array, transmitting, from the base station to the group of terminal devices, a synchronization signal using the precoding information, receiving time interval information from at least one terminal device of the group of terminal devices, the time interval information indicating a required maximum time interval for synchronizing the at least one terminal device, and determining schedule information indicating a schedule for transmitting the synchronization signal using the precoding information. ### Claim 2 (depends on 1) The method according to claim 1, wherein determining the precoding information comprises at least one of: determining the precoding information based on corresponding position information of each terminal device of the group of terminal devices, determining the precoding information based on corresponding previous precoding information, which has been used during previous communications between the base station and each terminal device of the group of terminal devices, selecting the precoding information from a predefined set of precoding information based on a pilot signal received from a terminal device, wherein the terminal device is assigned to the group of terminal devices, or selecting the precoding information from a predefined set of precoding information based on a report received from a terminal device of the group of terminal device, wherein the report indicates which precoding information provides a synchronization signal having the strongest level in the sub area in which the corresponding terminal device resides. ### Claim 3 (depends on 2) The method according to claim 2, wherein the position information comprises at least one of: a geographical position of the terminal device, a velocity of the terminal device, or a moving direction of the terminal device. ### Claim 4 (depends on 1) The method according to claim 1, further comprising: transmitting the schedule information from the base station to the group of terminal devices. ### Claim 5 (depends on 1) The method according to claim 1, further comprising: acquiring, at a terminal device of the group of terminal devices, timing and/or frequency information of the base station based on the synchronization signal transmitted from the base station, and transmitting a pilot signal from the terminal device to the base station based on the acquired timing and/or frequency information, the pilot signal being configured for a channel sounding of a radio frequency channel between the terminal device and base station for determining characteristics of the radio frequency channel. ### Claim 6 (depends on 5) The method according to claim 5, further comprising: receiving the pilot signal from the terminal device at the base station, determining further precoding information based on the pilot signal received from the terminal device, applying the further precoding information to the antenna array, and transmitting, from the base station to the terminal device, the synchronization signal using the further precoding information. ### Claim 7 (depends on 6) The method according to claim 6, further comprising: receiving, from the terminal device, time interval information, the time interval information indicating a required maximum time interval for synchronizing the terminal device, and determining further schedule information indicating a schedule for transmitting the synchronization signal using the further precoding information. ### Claim 8 (depends on 7) The method according to claim 7, further comprising: transmitting the further schedule information from the base station to the terminal device. ### Claim 9 (depends on 1) The method according to claim 1 corresponding transceiver is assigned, wherein applying the precoding information comprises at least one of: applying to each transceiver corresponding gain information provided by the precoding information, or applying to each transceiver corresponding phase information provided by the precoding information. ### Claim 10 (depends on 1) The method according to claim 1, wherein the synchronization signal comprises a sequence of synchronization signals. ### Claim 11 A base station, comprising: an antenna array having a plurality of antennas configured to communicate wirelessly with terminal devices positioned within a coverage area of the base station, a spatial transmission characteristic of the antenna array being configurable by applying precoding information, and a control unit configured to determine precoding information for concentrating a radio frequency power of a transmitted radio frequency signal to a group of terminal devices arranged in a sub area of the coverage area of the base station, to apply the determined precoding information to the antenna array, to transmit a synchronization signal using the precoding information, to receive time interval information from at least one terminal device of the group of terminal devices, the time interval information indicating a required maximum time interval for synchronizing the at least one terminal device, and to determine schedule information indicating a schedule for transmitting the synchronization signal using the precoding information. ### Claim 12 A terminal device, comprising at least one antenna configured to wirelessly communicate with a base station of a wireless communication network, a synchronization control unit configured to receive a sequence of synchronization signals from the base station, to acquire timing and/or frequency information of the base station based on the synchronization signals, and to transmit time interval information to the base station, the time interval information indicating a required maximum time interval for synchronizing the terminal device. ### Claim 13 (depends on 12) The terminal device according to claim 12, wherein the synchronization control unit is configured to receive schedule information from the base station, and to automatically change from an inactive state into an active state based on the received schedule information.