Low-PAPR Layered/Enhanced ACO-SCFDM for Optical-Wireless Communications

Abstract

In this letter, we propose layered/enhanced asymmetrically clipped optical single-carrier frequency-division multiplexing (L/E-ACO-SCFDM) for optical-wireless communications. L/E-ACO-SCFDM has a lower computational complexity and peak-to-average power ratio (PAPR) than L/E-ACO orthogonal frequency-division multiplexing (L/E-ACO-OFDM). The computational complexity of the simplified transmitter in L/EACO-SCFDM with R layers is (2 - 2/2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sup> )O(N), which is lower than the computational complexity of (2 - 2/2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sup> )O(Nlog <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> N) in L/E-ACO-OFDM. At a complementary cumulative distribution function of 10-3, the PAPR of L/E-ACO-SCFDM is approximately 4.2, 3.4, and 2.7 dB lower than that of L/E-ACO-OFDM for 2, 3, and 4 layers, respectively. The simulation results indicate that L/E-ACO-SCFDM has better performance than L/E-ACOOFDM under the transmitter nonlinearity and multipath fading.