Orthogonal time frequency space as a sixth generation enabler: A comprehensive analysis in high-mobility vehicular networks

Abstract

The sixth generation (6G) of wireless communication envisions a diverse range of use cases, including high-mobility vehicular networks, non-terrestrial satellite links, and ultra-reliable low-latency communication scenarios. Conventional multicarrier waveforms, such as orthogonal frequency division multiplexing (OFDM), demonstrate constraints in highly dynamic and Doppler-rich settings, presenting difficulties in achieving 6G performance standards. In this context, orthogonal time frequency space (OTFS) modulation has emerged as a promising candidate due to its delay-Doppler domain processing and robustness to time-variant channel impairments. This paper provides a unified performance evaluation of OTFS for 6G, investigating its bit error rate (BER), energy efficiency (EE), and peak-to-average power ratio (PAPR) under realistic channel models. EE analysis reveals a strong dependency on circuit power consumption and hardware efficiency, where OTFS maintains superior EE across mobility regimes, particularly in vital vehicular-to-everything (V2X) links. Finally, PAPR evaluations highlight the trade-off between transmit efficiency and signal quality, with OTFS offering a manageable PAPR profile that can be optimized through pulse shaping and power control techniques. Evaluating BER, EE, and PAPR for OTFS under realistic 6G channel models provides a unified perspective on its practical deployment potential. These results underline OTFS as a promising modulation candidate for 6G systems, balancing reliability, energy sustainability, and hardware feasibility in high-speed vehicular networks.