cess Physical Layer Aspects (Part 2) 515 The beamforming weights for data transmission are typically obtained from codebook-based CSI reporting. Once the codebook is specified, the beamforming capability in azimuth and elevation dimension is restricted by the codebook size, parameters, and structure. Alternatively, non-codebook-based beamforming can be extended to enable a gNB to reuse beam management procedures for acquiring the beamforming weights. In particular, a UE is configured with K > 1 CSI-RS resources, each associated with a TX beam. The beamform- ing can be performed in either digital or analog domain. However, in lower carrier frequen- cies, digital beamforming may be predominantly utilized. The UE measures the configured K CSI-RS resources and selects NCSI VI K CSI-RS resources based on their respective quali- ties and reports the NCSI CRIs. The actual CSI (e.g., CQI/PMI/RI) measured from the selected CSI-RS resources are also reported together with CRIs. As such, beam reporting and CSI reporting can be combined to acquire CSI. When a certain degree of channel reci- procity is achievable, beamforming weights can be derived at the gNB by measuring uplink signal(s) transmitted from the UE. The CSI reporting from the UE can also be utilized by the gNB to determine the beamforming weights [57]. To enable analog beamforming at the UE receiver, different reference signals within the resource set should be transmitted in different symbols, allowing the receiver-side beam to sweep over the set of reference signals. At the same time, the device can assume that different reference signals in the resource set are transmitted using the same spatial filter or alternatively the same transmit beam. In general, a configured resource set includes a repetition flag that indicates whether a device can assume that all reference signals within the resource set are transmitted using the same spatial filter. For a resource set to be used for downlink receiver-side beam adjustment, the repetition flag should be set [9]. 4.1