Analysis of nonlinear companding schemes for papr reduction of SC-FDMA signals

Abstract

The 3rd generation partnership project (3GPP) long term evolution (LTE) standard uses orthogonal frequency division multiplexing access (OFDMA) in downlink and single carrier frequency division multiple access (SC-FDMA) scheme for the uplink transmissions, which utilizes single carrier modulation and frequency domain equalization. In this paper, we compared and analyzed the performance of the nonlinear companding schemes, i.e., Raised-Cosine-like scheme and power function scheme, to reduce the peak-to-average power ratio (PAPR) of SC-FDMA signals, and summarized the nonlinear features that the schemes should have. Both the nonlinear schemes could transform the original SC-FDMA signals into nonlinear-distributed. Moreover, the schemes can compress the large input signals, while maintaining the average power constant. Computer simulation results show that the PAPR reduction performance of the power function scheme is better than that of the Raised-Cosine-like scheme.