NOMA NOMA SYSTEM USING USER GROUPING AND RECEIVER DIVERSITY AND SIGNAL TRANSMISSION METHOD THEREOF

摘要

The present invention relates to a non-orthogonal multiple access (NOMA) system using a user grouping and a receiving diversity and a signal transmitting method using the same. According to the present invention, the NOMA system using a user grouping and a receiving diversity comprises: a transmitting end which modulates each data signal to be transmitted to a plurality of user terminals, receives feedbacks on channel states from the plurality of user terminals to allocate power of the data signal according to the channel state, matches a data signal having the most power allocation with a data signal having the lest power allocation to make a group by subcarrier, and synthesizes grouped data signals to simultaneously transmit the same to each of user terminals; and a receiving end which receives the transmitted synthesized data signal to compensate channels, then demodulates the data signal having the most power allocation to extract the same, and extracts the data signal having the lest power allocation by using a successive interference cancellation (SIC) operations and maximal ration combining (MRC) techniques. According to the present invention, in a power-based NOMA system, user data is grouped for each subcarrier according to the channel states, and a subcarrier receiving diversity is used to improve a signal transmission performance.