A DST precoding based uplink NOMA scheme for PAPR reduction in 5G wireless network

Non-Orthogonal Multiple Access (NOMA) has become one of the potential candidate for the upcoming 5G wireless networks due to low latency, higher spectral efficiency, system throughput, and massive connectivity. The uplink NOMA can employ Orthogonal Frequency Division Multiplexing (OFDM) modulation for the construction of its basic primary signal waveform. The major weakness of uplink NOMA employing OFDM modulation is high Peak-to-Average Power Ratio (PAPR), which makes this scheme inefficient. Therefore, in this paper the Discrete-Sine Transform (DST) matrix precoding based uplink NOMA scheme has been proposed to reduce the higher PAPR. Computer simulations indicate that the DST matrix precoding based uplink NOMA scheme has lower PAPR as compared to the Walsh-Hadamard Transform (WHT) matrix precoding based uplink NOMA scheme and non-precoded uplink NOMA scheme available in the literature.