Anyone worked over refined beam for 5G FR1 if enabled in any network?
In that scenario does UE select best refined beam on the basis of CSI-RS or any change in mechanism?
Beam refinement mechanism is based on SSB (mandatory) or CSI-RS(optional) up to UE capability. However, most of the infravendors currently support both approaches.
In the case of DL Tx (gNB) Beam refinement (used to be called by P2 procedure), the eNB must configure TCI States (QCL Type, ReferenceSignal, TCI state ID, etc) through RRC signaling, on top of that, the UE must be configured with L1-RSRP reports. Only after receiving the L1 measurements reports the gNB might change the Beam through DCI or MAC-CE.
On the other hand, if the device is configured with DL UE Rx beam refinement (used to be called by P3 procedure), there is no need to report L1-RSRP and the decision is done autonomously by the UE.