PAPR Performance Analysis of SC-FDMA and SC-FDMA-DSCDMA

Orthogonal Frequency Division Multiple Access (OFDMA) is a new version of OFDM that allows multi-user access based on orthogonal frequency division by allocating time-frequency sub-channels to distinct users. OFDMA has numerous advantages, including increased power spectrum efficiency and reduced effect of the multipath channel. Despite the many advantages offered by OFDMA technology, which made it widely used, the OFDMA suffers from a high Peak-Average-powerRatio (PAPR) problem. SC-FDMA is one of the approaches proposed by 3GPP to reduce PAPR and is now used in 4G uplink. There is still a need to improve the SC-FDMA system’s performance by lowering the PAPR value. SC-FDMA-DSCDMA technology is proposed in this work, which is a hybrid technology that combines SC-FDMA with DS-CDMA technology. The proposed system was done upon multiple users, up to 128, using two modulation types (QPSK and 16PSK) with two kinds of subcarriers mapping (localized and interleaved). The simulation results proved that SC-FDMA-DS-CDMA has a better PAPR than SC-FDMA.