A transmitting apparatus, comprising: an encoder, configured to encode data for a plurality of user equipments into corresponding encoded signals, respectively; a modulator, configured to perform a joint modulation on the encoded signals for the plurality of user equipments to generate modulated signals, where the modulator performs the joint modulation by mapping bits of the encoded signals for the plurality of user equipments to a symbol corresponding to each constellation point of a constellation map of the modulated signals so that respective constellation points of the constellation map satisfy a Gray mapping rule; and a transmitter, configured to transmit the modulated signals, the transmitting apparatus is characterized in that the modulator determines a number of the bits of the encoded signals for the user equipments that are mapped to the symbol corresponding to each constellation point of the constellation map of the modulated signals according to a modulation and coding scheme assigned to each user equipment, wherein the transmitter is further configured to transmit control information for demodulating the modulated signals, the control information includes information indicating the modulation and coding scheme of each user equipment and information indicating an interference cancellation order of each user equipment, the information indicating the modulation and coding scheme of each user equipment is used to determine the number of bits of the encoded signals for the user equipment that are mapped to the symbol corresponding to each constellation point of the constellation map, and the information indicating the interference cancellation order of each user equipment is used to determine positions of the bits of the encoded signals for the user equipment that are mapped to the symbol corresponding to each constellation point of the constellation map. an encoder, configured to encode data for a plurality of user equipments into corresponding encoded signals, respectively; a modulator, configured to perform a joint modulation on the encoded signals for the plurality of user equipments to generate modulated signals, where the modulator performs the joint modulation by mapping bits of the encoded signals for the plurality of user equipments to a symbol corresponding to each constellation point of a constellation map of the modulated signals so that respective constellation points of the constellation map satisfy a Gray mapping rule; and a transmitter, configured to transmit the modulated signals, the transmitting apparatus is characterized in that the modulator determines a number of the bits of the encoded signals for the user equipments that are mapped to the symbol corresponding to each constellation point of the constellation map of the modulated signals according to a modulation and coding scheme assigned to each user equipment, wherein the transmitter is further configured to transmit control information for demodulating the modulated signals, the control information includes information indicating the modulation and coding scheme of each user equipment and information indicating an interference cancellation order of each user equipment, the information indicating the modulation and coding scheme of each user equipment is used to determine the number of bits of the encoded signals for the user equipment that are mapped to the symbol corresponding to each constellation point of the constellation map, and the information indicating the interference cancellation order of each user equipment is used to determine positions of the bits of the encoded signals for the user equipment that are mapped to the symbol corresponding to each constellation point of the constellation map.