Method and apparatus for group-based multi-beam operation

A base station (BS) comprising:

• a transceiver configured to:
• transmit a medium access control-control element (MAC-CE) activation command activating K groups of transmission configuration indicator (TCI) states, each group comprising multiple TCI states, where K>1, and
• transmit a downlink control information (DCI) field indicating a group of TCI states from the K groups of TCI states;
• and
• a processor operably coupled to the transceiver, the processor configured to identify multiple TCI states included in the indicated group of TCI states,
• wherein the transceiver is further configured to transmit a radio resource control (RRC) parameter,
• wherein the processor is further configured to determine, in accordance with the RRC parameter, at least one TCI state from the multiple TCI states, and
• wherein the transceiver is further configured to receive uplink (UL) channels/signals or transmit downlink (DL) channels/signals based on the at least one TCI state.

A method performed by a user equipment (UE), the method comprising:

• receiving a medium access control-control element (MAC-CE) activation command activating K groups of transmission configuration indicator (TCI) states, each group comprising multiple TCI states, where K>1;
• receiving a downlink control information (DCI) field indicating a group of TCI states from the K groups of TCI states;
• decoding the DCI field indicating the group of TCI states;
• identifying multiple TCI states included in the indicated group of TCI states;
• receiving a radio resource control (RRC) parameter;
• determining, based on the RRC parameter, at least one TCI state from the multiple TCI states;
• and
• transmitting uplink (UL) channels/signals or receive downlink (DL) channels/signals based on the at least one TCI state.