Method and device for performing communication by using non-orthogonal code multiple access scheme in wireless communication system

A UE performing communication based on a non-orthogonal coded multiple access scheme in a wireless communication system, the UE comprising:

• transmitter and a receiver for transmitting and receiving a radio signal;
• and
• a processor operatively coupled to the transmitter and the receiver, wherein the processor is configured to:
• receive control information from a base station;
• modulate or demodulate a UE specific NCC based on the control information;
• perform the non-orthogonal coded multiple access scheme based on the UE specific NCC,
• wherein the control information comprises information on a codeword configured in a Grassmannian sequence,
• wherein the codeword is included in a codebook predefined for the non-orthogonal coded multiple access scheme,
• wherein each coefficient of the Grassmannian sequence is quantized based on an M-QAM constellation, where M is a quantization level, and
• wherein, before being quantized with the M-QAM constellation, the Grassmannian sequence is scaled with a mean value of a magnitude of the M-QAM constellation and is normalized with a mean value of a magnitude of each coefficient of the codeword.