# US 12,603,741 B2 · Flexible intra-symbol multiplexing of DMRS of different antenna ports for single carrier waveform in higher bands > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,603,741 B2 - Document ID: US12603741B2 - Status: Granted - Kind: B2 - Application number: 17/316,669 - Filed: 2021-05-10 - Published: 2022-11-10 - Granted: 2026-04-14 - Earliest claimed: 2021-05-10 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Morteza Soltani; Jun Ma; Xiaoxia Zhang; Iyab Issam Sakhnini; Hemant Saggar - Web page: https://patentgrep.com/patent/US12603741B2 ## CPC - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/22: using time-division multiplexing - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for flexible intra-symbol multiplexing of DMRS of different antenna ports for single carrier waveforms. A base station may transmit one or more DMRSs within a symbol and provide an intra-symbol guard interval prior to each of the one or more DMRSs. The intra-symbol guard interval may have a duration that is based on a duration of a CP. A UE may receive the one or more demodulation reference signals DMRSs within the symbol based on the intra-symbol guard interval prior to each of the one or more DMRSs, and perform a channel estimation based on at least one of the one or more DMRSs. ## Claims ### Claim 1 An apparatus for wireless communication, comprising: a memory; and at least one processor coupled to the memory, wherein the at least one processor is configured to: transmit, within a symbol, one or more demodulation reference signals (DMRSs); and provide an intra-symbol guard interval prior to each DMRS of the one or more DMRSs, wherein the intra-symbol guard interval has a duration that is based on a duration of a cyclic prefix (CP), and wherein the intra-symbol guard interval is separate from the CP. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the at least one processor is configured to: time division multiplex (TDM) multiple DMRSs of different antenna ports with the intra-symbol guard interval between the multiple DMRSs, wherein the one or more DMRSs include the multiple DMRSs. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the at least one processor is configured to: code division multiplex (CDM) at least two of the multiple DMRSs of the different antenna ports within the symbol. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the at least one processor is configured to multiplex the one or more DMRSs with at least one physical downlink shared channel (PDSCH), and wherein the intra-symbol guard interval is positioned between the one or more DMRSs and the at least one PDSCH. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the duration of the intra-symbol guard interval for the symbol is equal to or greater than the duration of the CP for the symbol. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the duration of each of the one or more DMRSs is based on a corresponding channel condition for a user equipment (UE). ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the at least one processor is configured to: transmit a channel state information-reference signal (CSI-RS) to the UE; and receive channel estimation information from the UE, wherein the duration of at least one of the one or more DMRSs is based on the channel estimation information from the UE. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the at least one processor is configured to transmit a configuration to a user equipment (UE) for at least one of: a duration of the one or more DMRSs, a physical downlink shared channel (PDSCH) duration, the duration of the CP, or a number of antenna ports. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the at least one processor is configured to receive a sounding reference signal (SRS) from the UE, and wherein the configuration for the UE is based on the SRS. ### Claim 10 (depends on 8) The apparatus of claim 8, wherein a first duration of a first DMRS in the symbol is configured independently from a second duration of a second DMRS in the symbol. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the first duration of the first DMRS and the second duration of the second DMRS are based on respective channel conditions for each corresponding antenna port. ### Claim 12 A user equipment (UE) for wireless communication, comprising: a memory; and at least one processor coupled to the memory, wherein the at least one processor is configured to: receive a symbol, wherein the symbol includes one or more demodulation reference signals (DMRSs) and an intra-symbol guard interval prior to each DMRS of the one or more DMRSs, wherein the intra-symbol guard interval has a duration that is based on a duration of a cyclic prefix (CP), and wherein the intra-symbol guard interval is separate from the CP; and perform a channel estimation based on at least one of the one or more DMRSs. ### Claim 13 (depends on 12) The UE of claim 12, wherein the one or more DMRSs include a first DMRS and a second DMRS, wherein the first DMRS corresponds to a first antenna port and the second DMRS corresponds to a second antenna port, and wherein the intra-symbol guard interval is between the first DMRS and the second DMRS. ### Claim 14 (depends on 13) The UE of claim 13, wherein the first DMRS and the second DMRS are code division multiplexed (CDM). ### Claim 15 (depends on 12) The UE of claim 12, wherein the symbol includes the one or more DMRSs multiplexed with at least one physical downlink shared channel (PDSCH), and wherein the intra-symbol guard interval is positioned between the one or more DMRSs and the at least one PDSCH. ### Claim 16 (depends on 12) The UE of claim 12, wherein the duration of the intra-symbol guard interval for the symbol is equal to or greater than the duration of the CP for the symbol. ### Claim 17 (depends on 12) The UE of claim 12, wherein the duration of each of the one or more DMRSs is based on a corresponding channel condition associated with an antenna port. ### Claim 18 (depends on 17) The UE of claim 17, wherein the at least one processor is configured to: receive a channel state information-reference signal (CSI-RS) from a base station; and transmit channel estimation information to the base station, wherein the duration of at least one of the one or more DMRSs is based on the channel estimation information transmitted to the base station. ### Claim 19 (depends on 12) The UE of claim 12, wherein the at least one processor is configured to receive a configuration from a base station for at least one of: a duration of the one or more DMRSs, a physical downlink shared channel (PDSCH) duration, the duration of the CP, or a number of antenna ports. ### Claim 20 (depends on 19) The UE of claim 19, wherein the at least one processor is configured to transmit a sounding reference signal (SRS) to the base station, and wherein the configuration received from the base station is based on the SRS. ### Claim 21 (depends on 19) The UE of claim 19, wherein a first duration of a first DMRS in the symbol is configured independently from a second duration of a second DMRS in the symbol. ### Claim 22 (depends on 21) The UE of claim 21, wherein the first duration of the first DMRS and the second duration of the second DMRS are based on respective channel conditions for each corresponding antenna port. ### Claim 23 A method of wireless communication performed by a base station, comprising: transmitting, within a symbol, one or more demodulation reference signals (DMRSs); and providing an intra-symbol guard interval prior to each DMRS of the one or more DMRSs, wherein the intra-symbol guard interval has a duration that is based on a duration of a cyclic prefix (CP), and wherein the intra-symbol guard interval is separate from the CP. ### Claim 24 (depends on 23) The method of claim 23, further comprising time division multiplexing (TDM) multiple DMRSs of different antenna ports with the intra-symbol guard interval between the multiple DMRSs, wherein the one or more DMRSs include the multiple DMRSs. ### Claim 25 (depends on 23) The method of claim 23, further comprising multiplexing the one or more DMRSs with at least one physical downlink shared channel (PDSCH), wherein the intra-symbol guard interval is positioned between the one or more DMRSs and the at least one PDSCH. ### Claim 26 A method of wireless communication performed by a user equipment (UE), comprising: receiving a symbol, wherein the symbol includes one or more demodulation reference signals (DMRSs) and an intra-symbol guard interval prior to each DMRS of the one or more DMRSs, wherein the intra-symbol guard interval has a duration that is based on a duration of a cyclic prefix (CP), and wherein the intra-symbol guard interval is separate from the CP; and performing a channel estimation based on at least one of the one or more DMRSs. ### Claim 27 (depends on 26) The method of claim 26, further comprising receiving the one or more DMRSs within DMRSs of different antenna ports that are time division multiplexed (TDM) with the intra-symbol guard interval between the DMRSs of the different antenna ports. ### Claim 28 (depends on 26) The method of claim 26, wherein the symbol includes the one or more DMRSs multiplexed with at least one physical downlink shared channel (PDSCH), and wherein the intra-symbol guard interval is positioned between the one or more DMRSs and the at least one PDSCH.