FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and specifically, to techniques and apparatuses for determining one or more quasi co-location (QCL) relationships based on reference signals associated with different sets of QCL properties.

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 (for example, bandwidth, or transmit power, among other examples, or a combination thereof). 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).

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipments (UEs) to communicate on a municipal, national, regional, and even global level. New Radio (NR), which may also 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 (DL), using CP-OFDM or SC-FDMA (for example, also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL), 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.

In some cases, NR and similar radio access technologies (RATs) may support multicast operations to simultaneously disseminate data, such as emergency alerts or audio or video content, among many other possibilities, to multiple UEs that may be located in the same or different cells. In general, because multicast operations enable multiple UEs to receive the same data at substantially the same time, multicast operations can reduce network overhead relative to unicast operations in which a particular transmission is received by a single UE. In LTE, multicast operations are generally supported using enhanced multimedia broadcast/multicast service (eMBMS) and single-cell point-to-multipoint (SC-PTM) services. For example, in eMBMS, multicast data is transmitted in multiple cells in a particular area and the multicast data is received by a group of UEs that are located in the particular area. In SC-PTM, multicast data is transmitted in a particular cell and the multicast data is received by a group of UEs that are located in the particular cell. However, eMBMS and SC-PTM generally enable multicast transmissions via single-frequency network (SFN) configurations, where one or more transmitters send multicast data over a particular frequency channel. This poses challenges with respect to implementing support for multicast operations in NR and similar RATs in which both SFN and non-SFN operation may be supported.

SUMMARY

In some aspects, a method of wireless communication, performed by a user equipment (UE), may include obtaining measurements related to a plurality of reference signals received by the UE, wherein each of the plurality of reference signals is associated with a different set of quasi co-location (QCL) properties. The method may include determining a QCL property based at least in part on the measurements related to the plurality of reference signals. The method may include determining, based at least in part on the determined QCL property, a QCL relationship among the plurality of reference signals and a physical downlink shared channel (PDSCH). The method may include receiving the PDSCH based at least in part on the QCL relationship.

In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to obtain measurements related to a plurality of reference signals received by the UE, wherein each of the plurality of reference signals is associated with a different set of QCL properties. The memory and the one or more processors may be configured to determine a QCL property based at least in part on the measurements related to the plurality of reference signals. The memory and the one or more processors may be configured to determine, based at least in part on the determined QCL property, a QCL relationship among the plurality of reference signals and a PDSCH. The memory and the one or more processors may be configured to receive the PDSCH based at least in part on the QCL relationship.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to obtain measurements related to a plurality of reference signals received by the UE, wherein each of the plurality of reference signals is associated with a different set of QCL properties. The one or more instructions, when executed by the one or more processors of the UE, may cause the one or more processors to determine a QCL property based at least in part on the measurements related to the plurality of reference signals. The one or more instructions, when executed by the one or more processors of the UE, may cause the one or more processors to determine, based at least in part on the determined QCL property, a QCL relationship among the plurality of reference signals and a PDSCH. The one or more instructions, when executed by the one or more processors of the UE, may cause the one or more processors to receive the PDSCH based at least in part on the QCL relationship.

In some aspects, an apparatus for wireless communication may include means for obtaining measurements related to a plurality of reference signals received by the apparatus, wherein each of the plurality of reference signals is associated with a different set of QCL properties. The apparatus may include means for determining a QCL property based at least in part on the measurements related to the plurality of reference signals. The apparatus may include means for determining, based at least in part on the determined QCL property, a QCL relationship among the plurality of reference signals and a PDSCH. The apparatus may include means for receiving the PDSCH based at least in part on the QCL relationship.

Aspects generally include a method, device, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, transmit receive point, wireless communication device, network node, or processing system as substantially described with reference to and as illustrated by the drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples in accordance with the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

