Patent attributes
High transmission efficiency is realized by allowing extension to a number of ports greater than the conventional number of ports through efficient signaling. In a communication system, the highest number of ranks that is the number of spatial multiplex of transmission data transmitted to a terminal device from a base station is 8. The base station generates control information including 3-bit rank information indicating the rank of transmission data, and transmits the transmission data, a reference signal used for demodulating a physical downlink shared channel having the transmission data mapped, and the control information. The terminal device receives the transmission data, the reference signal, and the control information to identify the reference signal using the control information.
