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US-12627442-B2 - Demodulation reference signal resource allocation

US12627442B2US 12627442 B2US12627442 B2US 12627442B2US-12627442-B2

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit, to a network entity, demodulation reference signal (DMRS) capability information that indicates a number of orthogonal DMRS ports for DMRS communications. The UE may receive, from the network entity, information that is associated with a DMRS port mapping for the number of orthogonal DMRS ports and that indicates to restrict a resource allocation for a physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) to an integer that is a multiple of two for each contiguous physical resource block, to restrict a virtual resource block to physical resource block (VRB-to-PRB) mapping, or to restrict the number of orthogonal DMRS ports such that a legacy number of DMRS ports and an extended number of DMRS ports are not multiplexed in a same code division multiplexing (CDM) group. Numerous other aspects are described.

Inventors

  • Muhammad Sayed Khairy Abdelghaffar
  • Yi Huang
  • Yu Zhang

Assignees

  • QUALCOMM INCORPORATED

Dates

Publication Date
20260512
Application Date
20230314

Claims (20)

  1. 1 . An apparatus for wireless communication at a user equipment (UE), comprising: one or more memories; and one or more processors, coupled to the one or more memories, configured to: transmit, to a network entity, demodulation reference signal (DMRS) capability information that indicates a number of orthogonal DMRS ports for DMRS communications; and receive, from the network entity, information that is associated with a DMRS port mapping for the number of orthogonal DMRS ports and that indicates to: restrict a resource allocation for a physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) associated with the number of orthogonal DMRS ports to an integer that is a multiple of two for each contiguous physical resource block; restrict a virtual resource block to physical resource block (VRB-to-PRB) mapping for the number of orthogonal DMRS ports; or restrict the number of orthogonal DMRS ports, wherein a first number of DMRS ports and a second number of DMRS ports are not multiplexed in a same code division multiplexing (CDM) group, the first number of DMRS ports being based at least in part on a length two frequency domain orthogonal cover code (FD-OCC) and the second number of DMRS ports being based at least in part on a length four FD-OCC.
  2. 2 . The apparatus of claim 1 , wherein the first number of DMRS ports is a legacy number of DMRS ports, the second number of DMRS ports is an extended number of DMRS ports, and the UE is a multi-user UE.
  3. 3 . The apparatus of claim 1 , wherein the DMRS capability information is associated with a DMRS configuration type that uses every other resource element within one or more symbols allocated to the DMRS.
  4. 4 . The apparatus of claim 3 , wherein the number of orthogonal DMRS ports is eight ports for a single symbol DMRS for the DMRS configuration type or sixteen ports for a two symbol DMRS for the DMRS configuration type.
  5. 5 . The apparatus of claim 1 , wherein the information that indicates to restrict the VRB-to-PRB mapping for the number of orthogonal DMRS ports is included in a VRB-to-PRB mapping bitfield of downlink control information (DCI).
  6. 6 . The apparatus of claim 5 , wherein a value of the VRB-to-PRB mapping bitfield is zero or is not included in the DCI.
  7. 7 . The apparatus of claim 5 , wherein the information that indicates to restrict the VRB-to-PRB mapping for the number of orthogonal DMRS ports indicates that a plurality of PRBs associated with the number of orthogonal DMRS ports are non-interleaved or that the plurality of PRBs associated with the number of orthogonal DMRS ports are contiguous in a physical domain.
  8. 8 . The apparatus of claim 1 , wherein the information that indicates to restrict the VRB-to-PRB mapping for the number of orthogonal DMRS ports indicates that a number of VRB allocations is double a resource block bundle size.
  9. 9 . The apparatus of claim 8 , wherein the resource block bundle size is two resource blocks or four resource blocks.
  10. 10 . The apparatus of claim 1 , wherein the one or more processors, to receive the information that is associated with the DMRS port mapping, are configured to receive a PDSCH resource allocation that includes the information or a PUSCH resource allocation that includes the information.
  11. 11 . The apparatus of claim 1 , wherein the one or more processors are further configured to restrict resource allocation by scheduling PRBs for a PDSCH or PUSCH as contiguous PRBs in the frequency domain.
  12. 12 . The apparatus of claim 1 , wherein the one or more processors are further configured to determine the number of DMRS ports based on DMRS capability information transmitted by the UE.
  13. 13 . The apparatus of claim 1 , wherein the one or more processors are further configured to restrict allocation by performing a mapping between VRBs and PRBs according to an indication received from the network entity.
  14. 14 . The apparatus of claim 1 , wherein the one or more processors are further configured to, in response to receiving the information associated with the DMRS port mapping, apply a scheduling restriction that prevents assignment of DMRS ports based at least in part on a length two FD-OCC and DMRS ports based at least in part on a length four FD-OCC to the same CDM group.
  15. 15 . A method of wireless communication performed by a user equipment (UE), comprising: transmitting, to a network entity, demodulation reference signal (DMRS) capability information that indicates a number of orthogonal DMRS ports for DMRS communications; and receiving, from the network entity, information that is associated with a DMRS port mapping for the number of orthogonal DMRS ports and that indicates to: restrict a resource allocation for a physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) associated with the number of orthogonal DMRS ports to an integer that is a multiple of two for each contiguous physical resource block; restrict a virtual resource block to physical resource block (VRB-to-PRB) mapping for the number of orthogonal DMRS ports; or restrict the number of orthogonal DMRS ports, wherein a first number of DMRS ports and a second number of DMRS ports are not multiplexed in a same code division multiplexing (CDM) group, the first number of DMRS ports being based at least in part on a length two frequency domain orthogonal cover code (FD-OCC) and the second number of DMRS ports being based at least in part on a length four FD-OCC.
  16. 16 . The method of claim 15 , wherein the first number of DMRS ports is a legacy number of DMRS ports, the second number of DMRS ports is an extended number of DMRS ports, and the UE is a multi-user UE.
  17. 17 . The method of claim 15 , wherein the DMRS capability information is associated with a DMRS configuration type that uses every other resource element within one or more symbols allocated to the DMRS.
  18. 18 . The method of claim 15 , wherein the information that indicates to restrict the VRB-to-PRB mapping for the number of orthogonal DMRS ports is included in a VRB-to-PRB mapping bitfield of downlink control information (DCI).
  19. 19 . The method of claim 18 , wherein a value of the VRB-to-PRB mapping bitfield is zero or is not included in the DCI.
  20. 20 . The method of claim 18 , wherein the information that indicates to restrict the VRB-to-PRB mapping for the number of orthogonal DMRS ports indicates that a plurality of PRBs associated with the number of orthogonal DMRS ports are non-interleaved or that the plurality of PRBs associated with the number of orthogonal DMRS ports are contiguous in a physical domain.

Description

CROSS-REFERENCE TO RELATED APPLICATION This Patent Application claims priority to U.S. Provisional Patent Application No. 63/363,849, filed on Apr. 29, 2022, entitled “DEMODULATION REFERENCE SIGNAL RESOURCE ALLOCATION,” and assigned to the assignee hereof. The disclosure of the prior Application is considered part of and is incorporated by reference into this Patent Application. FIELD OF THE DISCLOSURE Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for demodulation reference signal resource allocation. BACKGROUND Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP). A wireless network may include one or more base stations that support communication for a user equipment (UE) or multiple UEs. A UE may communicate with a base station via downlink communications and uplink communications. “Downlink” (or “DL”) refers to a communication link from the base station to the UE, and “uplink” (or “UL”) refers to a communication link from the UE to the base station. The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different UEs to communicate on a municipal, national, regional, and/or global level. New Radio (NR), which may be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the 3GPP. NR is designed to better support mobile broadband internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink, using CP-OFDM and/or single-carrier frequency division multiplexing (SC-FDM) (also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink, as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR, and other radio access technologies remain useful. SUMMARY Some aspects described herein relate to a method of wireless communication performed by a user equipment (UE). The method may include transmitting, to a network entity, demodulation reference signal (DMRS) capability information that indicates a number of orthogonal DMRS ports for DMRS communications. The method may include receiving, from the network entity, information that is associated with a DMRS port mapping for the number of orthogonal DMRS ports and that indicates to restrict a resource allocation for a physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) associated with the number of orthogonal DMRS ports to an integer that is a multiple of two for each contiguous physical resource block, to restrict a virtual resource block to physical resource block (VRB-to-PRB) mapping for the number of orthogonal DMRS ports, or to restrict the number of orthogonal DMRS ports such that a first number of DMRS ports and a second number of DMRS ports are not multiplexed in a same code division multiplexing (CDM) group, wherein the first number of DMRS ports is based at least in part on a length two frequency domain orthogonal cover code (FD-OCC) and the second number of DMRS ports is based at least in part on a length four FD-OCC. Some aspects described herein relate to a method of wireless communication performed by a UE. The method may include transmitting, to a network entity, information associated with a VRB-to-PRB mapping for a DMRS. The method may include receiving, from the network entity, an indication to apply a FD-OCC to the DMRS for every three resource elements of the DMRS or every six resource elements of the DMRS. Some aspects described herein relate to an apparatus for wireless communication performed by a UE. The apparatus may include a memory and one or more processors, coupled to the memory. The one or more processors may be configured to transmit, to