Terminal, radio communication method, base station, and system to prevent deterioration of communication quality

A base station comprising:

• a transmitter that transmits, to a terminal, a medium access control-control element (MAC CE) activating one or more transmission configuration indicator (TCI) states among one or more TCI states configured by higher layer signaling;
• and
• a processor that determines a number of physical downlink shared channels (PDSCHs) to which receiving processing is performed by the terminal, based on higher layer signaling associated with time domain resource assignment for PDSCH,
• wherein the processor determines that the number of PDSCHs to which the receiving processing is performed is one if a number of TCI states indicated by downlink control information (DCI) among the one or more TCI states activated by the MAC CE is one, and determines that the number of PDSCHs to which the receiving processing is performed is two if a number of TCI states indicated by the DCI among the one or more TCI states activated by the MAC CE is two.

A system comprising a terminal and a base station:

• wherein
• the terminal comprises:
• a receiver that receives a medium access control-control element (MAC CE) activating one or more transmission configuration indicator (TCI) states among one or more TCI states configured by higher layer signaling;
• and
• a first processor that determines a number of physical downlink shared channels (PDSCHs) to which receiving processing is performed, based on higher layer signaling associated with time domain resource assignment for PDSCH,
• wherein the first processor determines that the number of PDSCHs to which the receiving processing is performed is one if a number of TCI states indicated by downlink control information (DCI) among the one or more TCI states activated by the MAC CE is one, and determines that the number of PDSCHs to which the receiving processing is performed is two if a number of TCI states indicated by the DCI among the one or more TCI states activated by the MAC CE is two;
• the base station comprises:
• a transmitter that transmits the MAC CE to the terminal;
• and
• a second processor that determines the number of PDSCH to which receiving processing is performed by the terminal.