# US 9,438,323 B2 · Method and device for sending user-specific reference signal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,323 B2 - Document ID: US9438323B2 - Status: Granted - Kind: B2 - Application number: 14/933,763 - Filed: 2015-11-05 - Published: 2016-02-25 - Granted: 2016-09-06 - Earliest claimed: 2013-05-10 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Tingjian Tian; Hua Yan; Lei Chen - Web page: https://patentgrep.com/patent/US9438323B2 ## CPC - H04B 7/024: Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems - H04B 1/0475: {with means for limiting noise, interference or distortion (H04B1/0483 takes precedence)} - H04B 7/0421: {utilizing implicit feedback, e.g. steered pilot signals} - H04B 7/0617: {for beam forming} - H04L 5/0023: {Time-frequency-space} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 9/40: Network security protocols - H04B 7/0413: MIMO systems - H04B 7/0456: Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting - H04L 5/0062: {Avoidance of ingress interference, e.g. ham radio channels} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Disclosed are a method and device for sending a user-specific reference signal. The method provided in the present invention includes: determining a modulus identification, and performing interference elimination processing on a user-specific reference signal according to the modulus identification to obtain the user-specific reference signal after the interference elimination processing; performing beamforming processing on the user-specific reference signal after the interference elimination processing to obtain a beamforming reference signal; and performing inverse fast fourier transform (IFFT) and digital-analog conversion on the beamforming reference signal to obtain an analog signal of the user-specific reference signal, and sending the analog signal to a user terminal. ## Claims ### Claim 1 A method for transmitting a user-specific reference signal, comprising: determining a modulus identification, and performing an interference elimination processing on the user-specific reference signal based on the modulus identification to obtain an interference-eliminated user-specific reference signal; performing a beamforming processing on the interference-eliminated user-specific reference signal to obtain a beamformed reference signal; and performing an inverse fast fourier transform (IFFT) and a digital-to-analogue conversion on the beamformed reference signal to obtain an analogue signal for the user-specific reference signal, and transmitting the analogue signal to a user terminal. ### Claim 2 (depends on 1) The method according to claim 1, wherein before the determining the modulus identification, the method further comprises: determining a modulus loss based on a difference between a signal-to-noise ratio obtained in a case that a modulus operation is performed on a data symbol and a signal-to-noise ratio obtained in a case that no modulus operation is performed on the data symbol; and determining a power loss based on a preset power factor. ### Claim 3 (depends on 2) The method according to claim 2, wherein the determining the modulus identification comprises: determining the modulus identification as 1 for instructing a modulus unit to perform the modulus operation on the data symbol, in a case that the modulus loss is less than the power loss; and the performing the interference elimination processing on the user-specific reference signal based on the modulus identification comprises: determining an interference elimination amount as 0, and performing no interference elimination processing on the user-specific reference signal, in a case that the modulus identification is 1. ### Claim 4 (depends on 2) The method according to claim 2, wherein the determining the modulus identification comprises: determining the modulus identification as 0 for instructing a modulus unit to perform no modulus operation on the data symbol, in a case that the modulus loss is greater than the power loss; and the performing the interference elimination processing on the user-specific reference signal based on the modulus identification comprises: determining an interference elimination amount with a preset approach, and performing the interference elimination processing on the user-specific reference signal according to the interference elimination amount, in a case that the modulus identification is 0. ### Claim 5 (depends on 4) The method according to claim 4, wherein before the performing the interference elimination processing on the user-specific reference signal based on the modulus identification, the method further comprises: performing power control on the user-specific reference signal based on the preset power factor, in a case that the modulus identification is 0. ### Claim 6 A base station, comprising: a processor; and a non-transitory processor-readable medium having processor-executable instructions stored thereon that, when executed by the processor, cause the base station to: determine a modulus identification; perform an interference elimination processing on a user-specific reference signal based on the modulus identification to obtain an interference-eliminated user-specific reference signal; perform a beamforming processing on the interference-eliminated user-specific reference signal to obtain a beamformed reference signal; perform an inverse fast fourier transform (IFFT) and a digital-to-analogue conversion on the beamformed reference signal to obtain an analogue signal for the user-specific reference signal; and transmit the analogue signal to a user terminal. ### Claim 7 (depends on 6) The base station according to claim 6, wherein the instructions further cause the base station to: determine values of a modulus loss and a power loss; wherein determining the modulus loss is based on a difference between a signal-to-noise ratio obtained in a case that a modulus operation is performed on a data symbol and a signal-to-noise ratio obtained in a case that no modulus operation is performed on the data symbol, and wherein determining the power loss is based on a preset power factor. ### Claim 8 (depends on 7) The base station according to claim 7, wherein: determining the modulus identification comprises: determining the modulus identification as 1 for instructing a modulus unit to perform the modulus operation on the data symbol, in a case that the modulus loss is less than the power loss; and performing the interference elimination processing comprises: determining an interference elimination amount as 0, and performing no interference elimination processing on the user-specific reference signal, in a case that the modulus identification is determined as 1. ### Claim 9 (depends on 7) The base station according to claim 7, wherein: determining the modulus identification comprises determining the modulus identification as 0 for instructing a modulus unit to perform no modulus operation on the data symbol, in a case that the modulus loss is greater than the power loss; and performing the interference elimination processing comprises determining an interference elimination amount with a preset approach, and performing an interference elimination processing on the user-specific reference signal according to the interference elimination amount, in a case that the modulus identification is determined as 0. ### Claim 10 (depends on 9) The base station according to claim 9, wherein the instructions further cause the base station to: perform power control on the user-specific reference signal based on the preset power factor, in a case that the modulus identification is determined as 0. ### Claim 11 A non-transitory computer-readable medium storing therein a set of processor-executable instructions that, when executed by a processor, cause the processor to execute the steps of: determining a modulus identification, and performing an interference elimination processing on a user-specific reference signal based on the modulus identification to obtain an interference-eliminated user-specific reference signal; performing a beamforming processing on the interference-eliminated user-specific reference signal to obtain a beamformed reference signal; and performing an inverse fast fourier transform (IFFT) and a digital-analogue conversion on the beamformed reference signal to obtain an analogue signal for the user-specific reference signal, and transmitting the analogue signal to a user terminal. ### Claim 12 (depends on 11) The non-transitory computer-readable medium according to claim 11, wherein the processor-executable instructions stored in the computer-readable medium further cause the processor to execute, before the determining the modulus identification, the steps of: determining a modulus loss based on a difference between a signal-to-noise ratio obtained in a case that a modulus operation is performed on a data symbol and a signal-to-noise ratio obtained in a case that no modulus operation is performed on the data symbol; and determining a power loss based on a preset power factor. ### Claim 13 (depends on 12) The non-transitory computer-readable medium according to claim 12, wherein the determining the modulus identification comprises: determining the modulus identification as 1 for instructing a modulus unit to perform the modulus operation on the data symbol, in a case that the modulus loss is less than the power loss; and the performing the interference elimination processing on the user-specific reference signal based on the modulus identification comprises: determining an interference elimination amount as 0, and performing no interference elimination processing on the user-specific reference signal, in a case that the modulus identification is 1. ### Claim 14 (depends on 12) The non-transitory computer-readable medium according to claim 12, wherein the determining the modulus identification comprises: determining the modulus identification as 0 for instructing a modulus unit to perform no modulus operation on the data symbol, in a case that the modulus loss is greater than the power loss; and the performing the interference elimination processing on the user-specific reference signal based on the modulus identification comprises: determining an interference elimination amount with a preset approach, and performing the interference elimination processing on the user-specific reference signal according to the interference elimination amount, in a case that the modulus identification is 0. ### Claim 15 (depends on 14) The non-transitory computer-readable medium according to claim 14, wherein the processor-executable instructions stored in the computer-readable medium further cause the processor to execute, before the performing the interference elimination processing on the user-specific reference signal based on the modulus identification, the steps of: performing power control on the user-specific reference signal based on the preset power factor, in a case that the modulus identification is 0.