Channel-Aware Hybrid Precoding and Gaussianized Companding for Energy-Efficient PAPR Reduction in Next-Generation Multicarrier Waveforms

Peak-to-Average Power Ratio (PAPR) remains a major limitation in multicarrier communication because large waveform peaks reduce power-amplifier efficiency and may degrade reliability and spectral containment while increasing energy consumption. This paper presents a Channel-Aware Hybrid Precoding and Gaussianized Companding (CA-HPGC) framework for energy-efficient PAPR reduction in OFDM, UFMC, and OTFS waveforms. The framework observes channel-state information, Signal-to-Noise Ratio, Doppler condition, modulation order, power-amplifier headroom, and quality-of-service requirements to select SRC, DCT, DHT, or hybrid precoding. It then applies selective Gaussianized companding only to statistically dominant envelope samples. A multi-objective controller jointly considers PAPR, bit-error rate, error vector magnitude, out-of-band emission, energy per bit, and latency. In the simulation-based evaluation, CA-HPGC reduces PAPR to 6.50 dB for UFMC and 6.10 dB for OTFS at CCDF of 10-3. At 20 dB SNR, the proposed OTFS achieves BER of 2.8×10-4, EVM of 2.40%, and OOB power of -45.10 dBm. Energy efficiency reaches 2.17 Mbit/J with 0.46 μJ/bit. These findings indicate that adaptive signal shaping can reduce peaks while preserving reliability and transmitter energy efficiency.