Low-complexity PAPR reduction scheme selective mapping cascading improved μ Law companding in CO-OFDM system

In this paper, a hybrid technique using a low complexity selective mapping (LCSLM) cascading an improved mu law companding scheme (LCSLM-mu) is proposed to reduce the peak-to-average power ratio (PAPR) and complexity in coherent optical orthogonal frequency division multiplexing system. The simulation results show that at the complementary cumulative distribution function of 10(-4), the PAPRs of the scheme LCSLM-mu(D = 4,m = 3, mu = 1) are optimized by 1.488 dB and 1.166 dB compared those of LCSLM (D = 4) and companding(mu = 1) schemes, respectively. Meanwhile, when the bit error rate (BER) is 10(-3), the optical signal to noise ratios (OSNRs) of the LCSLM-mu(D = 4,m = 3, mu = 1) scheme are optimized by 6.61 dB and 7.31 dB compared with those of companding (mu = 1) and improved mu law companding (m = 3, mu = 1) schemes, respectively. The computational complexity and PAPR reduction performance of various schemes, such as traditional SLM, LCSLM, improved law companding and LCSLM-mu schemes are analyzed respectively. The simulation results show that the LCSLM-mu (D = 4, m = 3, mu = 1) provides better PAPR reduction performance. When the alternative signal is 16, compared with the traditional SLM algorithm, the LCSLM-mu (D = 4, m = 3, mu = 1) scheme reduces the computational complexity of complex addition and complex multiplication by 53.1% and 45%, respectively. This paper provides a choice for a trade-off among PAPR reduction, BER and reduced complexity.