# US 12,191,958 B2 · Methods and apparatuses for phase tracking reference signal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,958 B2 - Document ID: US12191958B2 - Status: Granted - Kind: B2 - Application number: 17/641,334 - Filed: 2019-09-26 - Published: 2022-09-22 - Granted: 2025-01-07 - Earliest claimed: 2019-09-26 - Assignees: Lenovo (Beijing) Limited - Applicants: Lenovo (Beijing) Ltd. - Inventors: Bingchao Liu; Chenxi Zhu; Wei Ling; Lingling Xiao - Web page: https://patentgrep.com/patent/US12191958B2 ## CPC - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04B 7/0632: {Channel quality parameters, e.g. channel quality indicator [CQI]} - H04B 7/0639: {Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection} - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Methods and apparatuses for phase tracking reference signal are disclosed. A method comprises configuring a PT-RS with N PT-RS antenna ports when a ‘Transmission Configuration Indication (TCI)’ field in DCI indicates N TCI states, wherein N is 2 or more; associating each PT-RS antenna port with one DM-RS antenna port; and transmitting the PT-RS with the N PT-RS antenna ports. ## Claims ### Claim 1 A method comprising: configuring a phase tracking reference signal (PT-RS) with N PT-RS antenna ports when a ‘Transmission Configuration Indication (TCI)’ field in downlink control information (DCI) indicates N transmission configuration indication (TCI) states, wherein N is 2 or more; associating each PT-RS antenna port with one demodulation reference signal (DM-RS) antenna port, wherein each PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a different TCI state indicated by the TCI field in the DCI; and transmitting the PT-RS with the N PT-RS antenna ports. ### Claim 2 (depends on 1) The method of claim 1, further comprising: configuring a user equipment (UE) to report N layer indicators (LIs); and receiving the reported N LIs, wherein each of the N LIs indicates a strongest layer among layers reported by one of N precoding matrix indicators (PMI). ### Claim 3 (depends on 2) The method of claim 2, wherein, each of the strongest layers is assigned to one of the DM-RS antenna ports associated with the PT-RS antenna ports. ### Claim 4 (depends on 1) The method of claim 1, wherein, N is equal to 2, a first PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a first TCI state indicated by the TCI field in the DCI, and a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a second TCI state indicated by the TCI field in the DCI. ### Claim 5 A base unit for wireless communication, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the base unit to: configure a phase tracking reference signal (PT-RS) with N PT-RS antenna ports when a ‘Transmission Configuration Indication (TCI)’ field in downlink control information (DCI) indicates N transmission configuration indication (TCI) states, and associates each PT-RS antenna port with one demodulation reference signal (DM-RS) antenna port, wherein N is 2 or more, wherein each PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a different TCI state indicated by the TCI field in the DCI; and transmit the PT-RS with the N PT-RS antenna ports. ### Claim 6 (depends on 5) The base unit of claim 5, wherein the at least one processor is configured to cause the base unit to: configure a user equipment (UE) to report N layer indicators (LIs); and receive the reported N LIS, wherein each of the N LIs indicates a strongest layer among layers reported by one of N precoding matrix indicators (PMI). ### Claim 7 (depends on 6) The base unit of claim 6, wherein, each of the strongest layers is assigned to one of the DM-RS antenna ports associated with the PT-RS antenna ports. ### Claim 8 (depends on 6) The base unit of claim 6, wherein, two PMIs and single channel quality indicator (CQI) and two LIs are reported, a first LI indicates which column of the precoder matrix of a first reported PMI corresponds to the strongest layer, and a second LI indicates which column of the precoder matrix of a second reported PMI corresponds to the strongest layer. ### Claim 9 (depends on 6) The base unit of claim 6, wherein, two PMIs and two channel quality indicators (CQI) and two LIs are reported, a first LI indicates which column of the precoder matrix of the reported PMI corresponds to the strongest layer corresponding to a larger reported CQI, and a second LI indicates which column of the precoder matrix of the reported PMI corresponds to the strongest layer corresponding to another reported CQI. ### Claim 10 (depends on 6) The base unit of claim 6, wherein, two PMIs and two channel quality indicators (CQI) and two LIs are reported, a first LI indicates which column of the precoder matrix of the first reported PMI corresponds to the strongest layer, and a second LI indicates which column of the precoder matrix of the second reported PMI corresponds to the strongest layer. ### Claim 11 (depends on 10) The base unit of claim 10, wherein, two reported CQIs have equal value. ### Claim 12 (depends on 5) The base unit of claim 5, wherein, N is equal to 2, a first PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a first TCI state indicated by the TCI field in the DCI, and a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a second TCI state indicated by the TCI field in the DCI. ### Claim 13 (depends on 5) The base unit of claim 5, wherein, N is equal to 2, DM-RS type 1 or DM-RS type 2 is configured and two CDM groups are indicated by ‘antenna port(s)’ field in the DCI, a first PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a first indicated CDM group, and a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a second indicated CDM group. ### Claim 14 (depends on 5) The base unit of claim 5, wherein, N is equal to 2, DM-RS type 2 is configured and three code division multiplexing (CDM) groups are indicated by ‘antenna port(s)’ field in the DCI, a first PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a first indicated CDM group, and a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within two or more other indicated CDM groups. ### Claim 15 (depends on 5) The base unit of claim 5, wherein, N is equal to 3, DM-RS type 2 is configured and three code division multiplexing (CDM) groups are indicated by ‘antenna port(s)’ field in the DCI, a first PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a first indicated CDM group, a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a second indicated CDM group, and a third PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports within a third indicated CDM group. ### Claim 16 (depends on 5) The base unit of claim 5, wherein, N is equal to 2, two codewords are scheduled by the DCI, a first PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports assigned for a first codeword, and a second PT-RS antenna port is associated with the lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports assigned for a second codeword. ### Claim 17 A remote unit for wireless communications, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the remote unit to: receive a phase tracking reference signal (PT-RS) with N PT-RS antenna ports, wherein N is 2 or more, wherein the N PT-RS antenna ports is configured when a ‘Transmission Configuration Indication (TCI)’ field in downlink control information (DCI) indicates N transmission configuration indication (TCI) states, and each PT-RS antenna port is associated with a demodulation reference signal (DM-RS) antenna port, and wherein each PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a different TCI state indicated by the TCI field in the DCI. ### Claim 18 (depends on 17) The remote unit of claim 17, wherein the receiver further receives a configuration to report N layer indicators (LIs), and the remote unit further comprising a transmitter that reports N LIs, wherein each of the N LIs indicates a strongest layer among layers reported by one of N precoding matrix indicators (PMI). ### Claim 19 A processor for wireless communication, comprising: at least one controller coupled with at least one memory and configured to cause the processor to: receive a phase tracking reference signal (PT-RS) with N PT-RS antenna ports, wherein N is 2 or more, wherein the N PT-RS antenna ports is configured when a ‘Transmission Configuration Indication (TCI)’ field in downlink control information (DCI) indicates N transmission configuration indication (TCI) states, and each PT-RS antenna port is associated with a demodulation reference signal (DM-RS) antenna port, and wherein each PT-RS antenna port is associated with a lowest indexed DM-RS antenna port among the indicated DM-RS antenna ports associated with a different TCI state indicated by the TCI field in the DCI. ### Claim 20 (depends on 19) The processor of claim 19, wherein the at least one controller is configured to cause the processor to receive a configuration to report N layer indicators (LIs), and report N LIs, wherein each of the N LIs indicates a strongest layer among layers reported by one of N precoding matrix indicators (PMI).