Improving the peak-to-average power ratio of single-carrier frequency division multiple access systems by using an improved constellation extension scheme with error correction

Abstract

Single-carrier frequency division multiple access (SC-FDMA) is currently a widely used transmission technology that has been designated as the uplink transmission technology for the 4G mobile communications standard. SC-FDMA also has a lower peak-to-average power ratio (PAPR) compared with orthogonal frequency division multiple access (OFDMA), where OFDMA is the downlink transmission technology in the 4G standard. However, the PAPR of SC-FDMA increases with the M value in an M-ary modulation scheme, causing a decrease in the efficiency of high-power amplifiers at the transmission end. This study proposes a technique for minimizing the PAPR in SC-FDMA systems by dividing a 16-QAM product code (PC) into two subblocks, one of which is dedicated to encoding transmission data for enhanced error correction, and the other is for generating PAPR-reduction signals. Moreover, this study employed the constellation extension scheme to generate PAPR reduction signals because it can prevent additional data loss caused by the generated PAPR reduction signals. Simulation results show that the proposed technique not only reduces PAPR in SC-FDMA system, but its transmission signals also outperform conventional SC-FDMA signals in error correction because of the incorporated PCs.