Energy-Efficient 6G Wireless Waveforms: Leveraging Delay-Doppler Alignment Modulation

Energy efficiency is vital for sustainable 6G, especially in high-mobility, low-power applications. This paper evaluates the energy efficiency of three 6G waveforms: Delay-Doppler Alignment Modulation (DDAM), Orthogonal Time-Frequency Space (OTFS), and Orthogonal Frequency Division Multiplexing (OFDM). Energy efficiency is derived as the ratio of spectral efficiency to total power consumption, including transmission and processing power. Results show DDAM outperforms OTFS and OFDM due to its absence of cyclic prefix (CP), lower complexity, and efficient beamforming. OTFS has the highest power consumption due to CP overhead, high peak-to-average power ratio (PAPR), and complex equalization. While OTFS offers delay-Doppler resilience, it demands more processing power than DDAM. Simulations confirm DDAM's superior energy efficiency, especially in high-mobility scenarios where reduced equalization complexity enhances performance.