# US 12,120,667 B2 · Reference signal transmission method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,667 B2 - Document ID: US12120667B2 - Status: Granted - Kind: B2 - Application number: 17/737,526 - Filed: 2022-05-05 - Published: 2022-08-25 - Granted: 2024-10-15 - Earliest claimed: 2019-11-08 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Xianda Liu; Kunpeng Liu; Liuliu Ji - Web page: https://patentgrep.com/patent/US12120667B2 ## CPC - 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)} - H04W 72/1263: Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows - H04L 5/0035: {Resource allocation in a cooperative multipoint environment} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/0094: {Indication of how sub-channels of the path are allocated} - H04W 16/28: using beam steering - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - 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 This application provides a reference signal transmission method and an apparatus, used in a multipoint coordination transmission scenario. In one example method, a frequency domain resource that carries a target reference signal in a frequency domain resource or a time domain resource that is associated with each QCL assumption may be separately determined, and then the target reference signal carried on the frequency domain resource that is associated with the QCL assumption is separately received by using the corresponding QCL assumption. ## Claims ### Claim 1 A reference signal transmission method, comprising: determining a frequency domain density K of a target reference signal based on a quantity MRB of frequency domain resources; determining, based on the frequency domain density K, at least one of a third frequency domain resource that carries the target reference signal in a first frequency domain resource, or a fourth frequency domain resource that carries the target reference signal in a second frequency domain resource, wherein the quantity MRB of frequency domain resources is greater than zero and less than NRB, NRB is a quantity of scheduled frequency domain resources, and the scheduled frequency domain resources comprise the first frequency domain resource and the second frequency domain resource; and the first frequency domain resource is associated with a first quasi co-location (QCL) assumption, and the second frequency domain resource is associated with a second QCL assumption; and receiving, by using the first QCL assumption, the target reference signal carried on the third frequency domain resource, or receiving, by using the second QCL assumption, the target reference signal carried on the fourth frequency domain resource. ### Claim 2 (depends on 1) The method according to claim 1, wherein a target reference signal port corresponding to the target reference signal carried on the third frequency domain resource is associated with a demodulation reference signal (DMRS) port corresponding to a DMRS carried on the first frequency domain resource; or a target reference signal port corresponding to the target reference signal carried on the fourth frequency domain resource is associated with a DMRS port corresponding to a DMRS carried on the second frequency domain resource. ### Claim 3 (depends on 1) The method according to claim 1, wherein MRB is obtained by dividing NRB by NQCL and performing a ceiling operation, or is obtained by dividing NRB by NQCL and performing a floor operation; and NQCL is a total quantity of QCL assumptions associated with the scheduled frequency domain resources. ### Claim 4 (depends on 1) The method according to claim 1, wherein MRB is equal to a quantity of first frequency domain resources, or is equal to a quantity of second frequency domain resources. ### Claim 5 (depends on 1) The method according to claim 1, wherein the determining, based on the frequency domain density K, at least one of a third frequency domain resource that carries the target reference signal in a first frequency domain resource, or a fourth frequency domain resource that carries the target reference signal in a second frequency domain resource comprises: mapping a phase tracking reference signal (PTRS) once starting from a reference frequency domain resource block in the first frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the third frequency domain resource; or mapping a PTRS once starting from a reference frequency domain resource block in the second frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the fourth frequency domain resource. ### Claim 6 (depends on 1) The method according to claim 1, wherein the target reference signal is a reference signal used to perform channel estimation or used with a DMRS in performing channel estimation. ### Claim 7 (depends on 6) The method according to claim 6, wherein the target reference signal comprises a PTRS. ### Claim 8 A reference signal transmission method, comprising: determining a frequency domain density K of a target reference signal based on a quantity MRB of frequency domain resources; determining, based on the frequency domain density K, at least one of a third frequency domain resource that carries the target reference signal in a first frequency domain resource, or a fourth frequency domain resource that carries the target reference signal in a second frequency domain resource, wherein the quantity MRB of frequency domain resources is greater than zero and less than NRB, NRB is a quantity of scheduled frequency domain resources, and the scheduled frequency domain resources comprise the first frequency domain resource and the second frequency domain resource; and the first frequency domain resource is associated with a first quasi co-location (QCL) assumption, and the second frequency domain resource is associated with a second QCL assumption; and sending, by using the first QCL assumption, the target reference signal carried on the third frequency domain resource, or sending, by using the second QCL assumption, the target reference signal carried on the fourth frequency domain resource. ### Claim 9 (depends on 8) The method according to claim 8, wherein a target reference signal port corresponding to the target reference signal carried on the third frequency domain resource is associated with a DMRS port corresponding to a demodulation reference signal DMRS carried on the first frequency domain resource; and/or a target reference signal port corresponding to the target reference signal carried on the fourth frequency domain resource is associated with a DMRS port corresponding to a DMRS carried on the second frequency domain resource. ### Claim 10 (depends on 8) The method according to claim 8, wherein MRB is obtained by dividing NRB by NQCL and performing a ceiling operation, or is obtained by dividing NRB by NQCL and performing a floor operation; and NQCL is a total quantity of QCL assumptions associated with the scheduled frequency domain resources. ### Claim 11 (depends on 8) The method according to claim 8, wherein MRB is equal to a quantity of first frequency domain resources, or is equal to a quantity of second frequency domain resources. ### Claim 12 (depends on 8) The method according to claim 8, wherein the determining, based on the frequency domain density K, at least one of a third frequency domain resource that carries the target reference signal in a first frequency domain resource, or a fourth frequency domain resource that carries the target reference signal in a second frequency domain resource comprises: mapping a phase tracking reference signal (PTRS) once starting from a reference frequency domain resource block in the first frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the third frequency domain resource; or mapping a PTRS once starting from a reference frequency domain resource block in the second frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the fourth frequency domain resource. ### Claim 13 (depends on 8) The method according to claim 8, wherein the target reference signal is a reference signal used to perform channel estimation or used with a DMRS in performing channel estimation. ### Claim 14 (depends on 13) The method according to claim 13, wherein the target reference signal comprises a PTRS. ### Claim 15 An apparatus, comprising: a receiver; at least one processor; and one or more memories coupled to the at least one processor and storing programming instructions for execution by the at least one processor to cause the apparatus to: determine a frequency domain density K of a target reference signal based on a quantity MRB of frequency domain resources; determine based on the frequency domain density K, a third frequency domain resource that carries the target reference signal in a first frequency domain resource, or a fourth frequency domain resource that carries the target reference signal in a second frequency domain resource, wherein the quantity MRB of frequency domain resources is greater than zero and less than NRB, NRB is a quantity of scheduled frequency domain resources, and the scheduled frequency domain resources comprise the first frequency domain resource and the second frequency domain resource; and the first frequency domain resource is associated with a first quasi co-location (QCL) assumption, and the second frequency domain resource is associated with a second QCL assumption; and receive by using the first QCL assumption, the target reference signal carried on the third frequency domain resource, or receive, by using the second QCL assumption, the target reference signal carried on the fourth frequency domain resource. ### Claim 16 (depends on 15) The apparatus according to claim 15, wherein a target reference signal port corresponding to the target reference signal carried on the third frequency domain resource is associated with a demodulation reference signal (DMRS) port corresponding to a DMRS carried on the first frequency domain resource; or a target reference signal port corresponding to the target reference signal carried on the fourth frequency domain resource is associated with a DMRS port corresponding to a DMRS carried on the second frequency domain resource. ### Claim 17 (depends on 15) The apparatus according to claim 15, wherein MRB is equal to a quantity of first frequency domain resources, or is equal to a quantity of second frequency domain resources. ### Claim 18 (depends on 15) The apparatus according to claim 15, wherein the programming instructions, when executed by the at least one processor, cause the apparatus to: map a phase tracking reference signal (PTRS) once starting from a reference frequency domain resource block in the first frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the third frequency domain resource; or map a PTRS once starting from a reference frequency domain resource block in the second frequency domain resource at an interval of K frequency domain resource blocks, to obtain frequency domain resource blocks that carry the target reference signal as the fourth frequency domain resource. ### Claim 19 (depends on 15) The apparatus according to claim 15, wherein the target reference signal is a reference signal used to perform channel estimation or used with a DMRS in performing channel estimation. ### Claim 20 (depends on 19) The apparatus according to claim 19, wherein the target reference signal comprises a PTRS.