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arXiv · 2604.22478

Time-Frequency Pilot Sequence Design and LoS Delay-Doppler Estimation

Aadarsh Devanand·Praful D. Mankar
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Abstract

We present a novel framework for line-of-sight (LoS) delay-Doppler (DD) estimation in dense scattering propagation environments. We present two time-frequency (TF) domain pilot sequences inspired by the Zadoff-Chu sequence that exhibit desirable autocorrelation properties. Further, we present a twisted convolution-based approach for LoS DD estimation directly from the TF-domain received signal, avoiding an additional TF to DD transformation, which is commonly found in literature. Numerical results from simulations demonstrate that the proposed framework significantly outperforms traditional single-carrier Zadoff-Chu sequences in both delay and Doppler estimation over a wide range of Rician fading factor and SNR values.

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Aadarsh Devanand, Praful D. Mankar. 2026-04-24. Time-Frequency Pilot Sequence Design and LoS Delay-Doppler Estimation. https://arxiv.org/abs/2604.22478

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