Wireless communication systems for selecting one or more antenna ports for downlink transmission

A base station (BS) that selects one or more antennas in a wireless communication system, the BS comprising:

• memory;
• at least one transceiver;
• and
• at least one processor, coupled to the memory and the transceiver, the at least one processor configured to:
• transmit, to one or more user equipment (UE), one or more initial synchronization signal blocks (SSB) and one or more initial channel state information-reference signals (CSI-RS) using a plurality of antenna ports;
• transmit a demodulation reference signal (DMRS) to the one or more UE,
• receive, from the one or more UE, signals including at least one parameter indicative of corresponding operating conditions at the one or more UE in response to (i) the transmitted one or more initial SSB and CSI-RS and (ii) the transmitted DMRS, the at least one parameter including signal to interference and noise ratio (SINR) measurements generated based on the DMRS;
• select one or more antenna ports among the plurality of antenna ports based on the received at least one parameter;
• adjust transmission power of a SSB and a CSI-RS based on the SINR;
• and
• transmit the SSB and the CSI-RS based on the adjusted SSB and CSI-RS transmission power using the selected one or more antenna ports.