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arXiv · 2606.16750

Data-Aided Channel and Doppler Estimation for mMIMO LEO SatComs with Uncompensated Doppler

Abdollah Masoud Darya·Saeed Abdallah
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Abstract

This paper presents a framework for estimating and tracking massive multiple-input multiple-output (mMIMO) low-Earth-orbit (LEO) satellite channels under uncompensated Doppler. The approach begins with a pilot-based minimum mean square error (MMSE) estimate, followed by Doppler estimation and data-aided channel estimation using either a decision-directed MMSE (DD-MMSE) or an expectation-maximization (EM)-based estimator. The proposed framework achieves improved channel and Doppler estimation accuracy compared to existing methods. Results demonstrate that the DD-MMSE variant offers lower complexity, while the EM variant provides higher estimation accuracy.

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Abdollah Masoud Darya, Saeed Abdallah. 2026-06-15. Data-Aided Channel and Doppler Estimation for mMIMO LEO SatComs with Uncompensated Doppler. https://doi.org/10.1109/lwc.2026.3704614

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