If the UL-based DL beam association is supported at operation 557, the terminal performs UL BM along with the base station at operation 571. At operation 573, the terminal receives UL BM-based DL BPL indication and UL BM-based UL BPL indication from the base station. At operation 575, the terminal may receive a DL signal, a channel, data or control information from the base station based on the UL BM-based DL BPL indication, and may transmit an UL signal, a channel, data or control information to the base station based on the UL BM-based UL BPL indication.

If the DL-based UL beam association is supported at operation 555, the terminal may perform DL BM along with the base station at operation 581. At operation 583, the terminal may receive DL BM-based DL BPL indication and DL BM-based UL BPL indication from the base station. At operation 585, the terminal may receive a DL signal, a channel, data or control information from the base station based on the DL BM-based DL BPL indication, and may transmit an UL signal, a channel, data or control information to the base station based on the DL BM-based UL BPL indication.

The third embodiment is an embodiment in which a BPL established through UL BM is applied DL transmission. A representative scenario of the third embodiment includes a case where a BPL established through an UL SRS (used in UL BM) is used for a DL CSI-RS/DL DMRS/PDCCH/PDSCH. For the third embodiment, a base station may provide a terminal with the following two indications (i.e., indication for an UL-based DL beam association and a DL BPL indication).

1. Indication for UL-Based DL Beam Association.