BER-Conscious PAPR Mitigation Techniques for Downlink CP-OFDM System

The advent of Release-20 meetings in 3rdGeneration Partnership Project (3GPP) saw a mutual agreement among various participants on the use of cyclic-prefix orthogonal frequency domain multiplexing (CP-OFDM) and Discrete Fourier Transform-spread Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) as the baseline for waveforms study in 6thGeneration (6G). This article compares several peak-to-average-power-ratio (PAPR) reduction strategies for CP-OFDM, such as clipping, Selected Mapping (SLM), and Tone Reservation (TR). The simulation looks into bit error rate (BER) and PAPR performances to find efficient trade-offs between signal fidelity and power efficiency. According to the results, clipping reduces PAPR the most, followed by SLM, whereas TR very slightly improves PAPR. SLM and TR continue to perform similarly to the baseline OFDM in terms of BER, whereas clipping introduces a minor deterioration because of nonlinear distortion. Further parametric simulations show that while increasing the number of SLM phase candidates efficiently lowers PAPR without compromising BER, decreasing the clipping softness factor improves BER but increases PAPR. Overall, the study shows that by carefully choosing and fine-tuning reduction techniques, a reasonable balance between PAPR reduction and error performance may be achieved.