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

TL;DR

This paper introduces a new framework for LoS delay-Doppler estimation using specially designed TF domain pilot sequences and a twisted convolution method, outperforming traditional approaches in simulations.

Contribution

The paper proposes a novel TF domain pilot sequence design and a twisted convolution-based estimation method that directly estimates LoS DD from received signals, avoiding extra transformations.

Findings

Significantly improved delay and Doppler estimation accuracy in simulations.

Outperforms traditional Zadoff-Chu sequences across various SNR and fading conditions.

Demonstrates robustness of the proposed method in dense scattering environments.

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.