A base station apparatus configured to communicate with a terminal apparatus (2-1, 2-2), the base station apparatus comprising: a transmission unit configured to transmit downlink data by using a physical downlink shared channel, PDSCH, and transmit downlink control information, DCI, through a physical downlink control channel, PDCCH; and a modulation unit configured to take encoded bits in the PDSCH as input and produce modulation symbols by using a first modulation mapping or a second modulation mapping, wherein in a case that a superposition coding is configured, the DCI includes first information indicating a power ratio and the modulation unit is configured to take the encoded bits in the PDSCH and a plurality of bits as input and produce the modulation symbols by using the first modulation mapping based on the first information in which the first information is generated individually for every transport block, the power ratio is a power ratio of the plurality of bits to the encoded bits for the terminal apparatus, and the plurality of bits are not for the terminal apparatus, and in a case that the superposition coding is not configured, the modulation unit is configured to take the encoded bits in the PDSCH as input and produce the modulation symbols by using the second modulation mapping. a transmission unit configured to transmit downlink data by using a physical downlink shared channel, PDSCH, and transmit downlink control information, DCI, through a physical downlink control channel, PDCCH; and a modulation unit configured to take encoded bits in the PDSCH as input and produce modulation symbols by using a first modulation mapping or a second modulation mapping, wherein in a case that a superposition coding is configured, the DCI includes first information indicating a power ratio and the modulation unit is configured to take the encoded bits in the PDSCH and a plurality of bits as input and produce the modulation symbols by using the first modulation mapping based on the first information in which the first information is generated individually for every transport block, the power ratio is a power ratio of the plurality of bits to the encoded bits for the terminal apparatus, and the plurality of bits are not for the terminal apparatus, and in a case that the superposition coding is not configured, the modulation unit is configured to take the encoded bits in the PDSCH as input and produce the modulation symbols by using the second modulation mapping. in a case that a superposition coding is configured, the DCI includes first information indicating a power ratio and the modulation unit is configured to take the encoded bits in the PDSCH and a plurality of bits as input and produce the modulation symbols by using the first modulation mapping based on the first information in which the first information is generated individually for every transport block, the power ratio is a power ratio of the plurality of bits to the encoded bits for the terminal apparatus, and the plurality of bits are not for the terminal apparatus, and in a case that the superposition coding is not configured, the modulation unit is configured to take the encoded bits in the PDSCH as input and produce the modulation symbols by using the second modulation mapping.