PAPR Reduction Using Discrete Forest Optimization Algorithm Based on SLM Technique in Intensity Modulated Direct Detection Optical OFDM Communication Systems

In intensity-modulated direct detection optical orthogonal frequency division multiplexing (IM/DD-OOFDM) communication systems, a lower peak-to-average power ratio (PAPR) is essential for improving system performance. In order to reduce the high PAPR, a discrete forest optimization algorithm (DFOA) is integrated with the classical selective mapping (SLM) method in IM/DD-OFDM system. This approach successfully optimizes the values of phase factors, minimizes the search numbers, and reduces computational complexity. To evaluate the impact of the DFOA-SLM method on PAPR reduction, the parameters of the DFOA-SLM method play a crucial role in decreasing the PAPR in an IM/DD optical OFDM system. The DFOA-SLM method demonstrates improved bit error rate (BER) performance, power spectral density (PSD), and power saving performance compared with other PAPR reduction methods. Numerical results indicate that the proposed PAPR reduction method outperforms existing other methods for optical OFDM signals. Specifically, by implementing this technique in the IM/DD optical OFDM communication system, we achieved a decrease in PAPR from 10.68 to 4.88 dB at a complementary cumulative distribution function (CCDF) of 10⁻³, resulting in a reduction of 5.8 dB. Additionally, the computational complexity of the DFOA-SLM method shows a 73.63% improvement over the classical SLM method when the search number is set to 512.