A Novel Delay-Doppler Domain Channel Sounding Method for 6G High-Mobility Scenarios

TL;DR

This paper introduces a new delay-Doppler domain channel sounding method tailored for 6G high-mobility scenarios, enabling accurate characterization of propagation environments with high mobility.

Contribution

The paper proposes a novel DD domain channel sounding technique, including waveform design, synchronization, CSF estimation, and an enhancement algorithm, specifically for 6G high-mobility environments.

Findings

Effective measurement of CSF and Doppler characteristics in urban V2I scenarios.

Demonstrated improved measurement precision over existing methods.

Confirmed the method's capability to characterize high-mobility propagation environments.

Abstract

Channel measurements are the prerequisite for applying emerging transmission technologies and designing communication systems. In sixth-generation (6G) system, conventional time or frequency domain channel sounding methods cannot directly obtain Doppler information induced by high-mobility scenarios. The channel spreading function (CSF) simultaneously captures delay and Doppler information, while naturally characterizing the propagation environment in the delay-Doppler (DD) domain. However, DD domain channel sounding methods remain underexplored. This paper presents a novel DD domain channel sounding method for 6G high-mobility scenarios. First, we introduce the waveform design for the sounding signal and analyze its sounding capability. Next, the methodology of DD domain channel sounding, including synchronization and CSF estimation, is thoroughly detailed. Additionally, an algorithm for enhancing measurement precision is proposed. The performance of the proposed method is rigorously evaluated. Subsequently, a DD domain channel sounding system competent for 6G high-mobility scenarios is established. Finally, DD domain channel measurements are conducted for a vehicle-to-infrastructure scenario in urban environments. Measurement results, including CSF, power delay profile, Doppler power spectral density, number of multipath components, and other characteristics, are derived, which confirm the effectiveness of the proposed method and offer helpful insights for advancing research on 6G high-mobility communications.