Abstract: Methods and apparatuses for channel state information reference signal in wireless communication systems are provided. The methods of BS comprise: identifying first information corresponding to a number of antenna ports associated with transmissions of CSI-RSs; identifying, a first size of CDM groups associated with the number of antenna ports and a first shape of the CDM groups; identifying second information from the first information; identifying a starting SC index and a starting symbol index; identifying, based on the number of antenna ports associated with a CSI-RS transmission and a predetermined frequency domain granularity of channel state information, a size of RB cluster for the resource allocation; and transmitting, to a UE, resource configuration information indicating at least one of the size of RB cluster, the first size of the CDM groups, the first shape of the CDM groups, the starting SC index, and the starting symbol index.

Abstract: Methods and apparatuses for channel state information reporting in advanced MIMO antenna systems is provided. The method comprises: receiving information for an analog beam and an R CSI-RS resources; constructing an analog beam codebook; deriving sets of PMIs corresponding to analog beams, wherein each set of R sets of PMIs corresponds to an analog beam of the analog beams associated with the R CSI-RS resources; identifying a set of digital beams corresponding to each of the analog beams; identifying a set of hybrid beams corresponding to each of the R CSI-RS resources, wherein the set of the hybrid beams comprises the set of digital beams and the analog beam, respectively; identifying a subset of the set of hybrid beams using an index to generate a PMI corresponding to the analog beams; and transmitting a CSI report including the PMI and the subset of the set of hybrid beams.

Abstract: Aspects of this disclosure relate to scheduling wireless communications based on channel estimate aging. Channel estimates can be generated based on signals wirelessly transmitted by user equipments. Aging metrics associated with the channel estimates can be determined. Wireless communications with at least some of the user equipments can be scheduled based on the aging metrics.

Abstract: A method of a base station (BS) for channel state information (CSI) estimation in a wireless communication system is provided. The method of BS comprises: receiving, from a user equipment (UE), a sounding reference signal (SRS) for the CSI estimation; determining whether the received SRS is measurable for the CSI estimation; initializing a set of uplink parameters based on a result of the determination; updating the set of uplink parameters based on SRS history stored in a buffer; and performing, using a channel prediction model and channel reciprocity, the downlink CSI estimation based on the updated parameters.

Abstract: A method of a base station (BS) for channel state information (CSI) estimation in a wireless communication system is provided. The method of BS comprises: receiving, from a user equipment (UE), a sounding reference signal (SRS) for the CSI estimation; determining whether the received SRS is measurable for the CSI estimation; initializing a set of uplink parameters based on a result of the determination; updating the set of uplink parameters based on SRS history stored in a buffer; and performing, using a channel prediction model and channel reciprocity, the downlink CSI estimation based on the updated parameters.