Data transmission method and data transmission device

A user equipment receiving control data in a wireless communication system, the user equipment comprising a processor,

• wherein the processor is configured to demodulate downlink control information (DCI) including an assignment flag and a downlink (DL) resource allocation and
• to demodulate PDSCH (physical downlink shared channel) data by using the DL resource allocation,
• wherein when the PDSCH data is demodulated based on a demodulation reference signal (DM-RS), the assignment flag indicates information on a reference signal (RS) used for demodulating the PDSCH data or information on a transmit antenna port of the PDSCH,
• wherein when the PDSCH data is demodulated based on a cell-specific RS, the assignment flag indicates a localized virtual resource block (LVRB) assignment or a distributed virtual resource block (DVRB) assignment for a PDSCH,
• wherein the LVRB assignment indicates at least one physical resource block (PRB) at a same position on a frequency domain,
• wherein the DVRB assignment indicates at least one PRB at a distributed positions on the frequency domain,
• wherein the assignment flag has one bit,
• wherein the DM-RS is generated from a pseudo-random sequence initialized by a scramble identifier,
• wherein the scramble identifier is given by a base station, and
• wherein the cell-specific RS is generated from a pseudo-random sequence initialized by a cell identifier.