A data transmission method, wherein the method comprises: receiving (S101, S201) a downlink channel quality indicator fed back by first user equipment, and determining a first downlink modulation and coding scheme of the first user equipment according to the downlink channel quality indicator fed back by the first user equipment; allocating (S102, S202) a transmission resource of a first cell to the first user equipment according to the first downlink modulation and coding scheme of the first user equipment, wherein the first cell is a serving cell of the first user equipment; characterized in that: acquiring (S103, S203) an uplink channel matrix of a sub-bandwidth level of each cell in a measurement set of the first user equipment, wherein the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment is determined according to a sounding reference signal sent by the first user equipment to a first base station, and the first base station is a base station to which each cell in the measurement set of the first user equipment belongs; determining (S104, S204), according to the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment, a signal to interference plus noise ratio of a downlink transmission stream to be sent by each cell in a transmission set of the first user equipment, wherein the transmission set of the first user equipment is a subset of the measurement set of the first user equipment; and determining (S105, S205) a second downlink modulation and coding scheme of the first user equipment according to the signal to interference plus noise ratio of the downlink transmission stream to be sent. receiving (S101, S201) a downlink channel quality indicator fed back by first user equipment, and determining a first downlink modulation and coding scheme of the first user equipment according to the downlink channel quality indicator fed back by the first user equipment; allocating (S102, S202) a transmission resource of a first cell to the first user equipment according to the first downlink modulation and coding scheme of the first user equipment, wherein the first cell is a serving cell of the first user equipment; characterized in that: acquiring (S103, S203) an uplink channel matrix of a sub-bandwidth level of each cell in a measurement set of the first user equipment, wherein the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment is determined according to a sounding reference signal sent by the first user equipment to a first base station, and the first base station is a base station to which each cell in the measurement set of the first user equipment belongs; determining (S104, S204), according to the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment, a signal to interference plus noise ratio of a downlink transmission stream to be sent by each cell in a transmission set of the first user equipment, wherein the transmission set of the first user equipment is a subset of the measurement set of the first user equipment; and determining (S105, S205) a second downlink modulation and coding scheme of the first user equipment according to the signal to interference plus noise ratio of the downlink transmission stream to be sent. acquiring (S103, S203) an uplink channel matrix of a sub-bandwidth level of each cell in a measurement set of the first user equipment, wherein the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment is determined according to a sounding reference signal sent by the first user equipment to a first base station, and the first base station is a base station to which each cell in the measurement set of the first user equipment belongs; determining (S104, S204), according to the uplink channel matrix of the sub-bandwidth level of each cell in the measurement set of the first user equipment, a signal to interference plus noise ratio of a downlink transmission stream to be sent by each cell in a transmission set of the first user equipment, wherein the transmission set of the first user equipment is a subset of the measurement set of the first user equipment; and determining (S105, S205) a second downlink modulation and coding scheme of the first user equipment according to the signal to interference plus noise ratio of the downlink transmission stream to be sent.