Low PAPR Pilot for Delay-Doppler Domain Modulation

This paper studies the low PAPR pilot design in delay-Doppler domain modulation. We adopt a sequence based pilot design instead of the conventional pulse pilot, to mitigate the PAPR issue. We develop simple channel estimation algorithm composes of two-stages which are path identification and channel coefficient estimation. The quantitative analysis on the channel estimation error model is provided. Based on which the principle of pilot sequence design in delay-Doppler domain is revealed. Experiment results shows that the proposed scheme maintains a relatively low PAPR in time domain samples, while the channel estimation performance approaches the ideal channel estimation in limited-Doppler-Shift channel model.