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arXiv · 2111.12382

Compressed Sensing Channel Estimation for OTFS Modulation in Non-Integer Delay-Doppler Domain

Felipe Gómez-Cuba
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Abstract

This paper introduces a Compressed Sensing (CS) estimation scheme for Orthogonal Time Frequency Space (OTFS) channels with sparse multipath. The OTFS waveform represents signals in a two dimensional Delay-Doppler (DD) orthonormal basis. The proposed model does not require the assumption that the delays are integer multiples of the sampling period. The analysis shows that non-integer delay and Doppler shifts in the channel cannot be accurately modelled by integer approximations. An Orthogonal Matching Pursuit with Binary-division Refinement (OMPBR) estimation algorithm is proposed. The proposed estimator finds the best channel approximation over a continuous DD dictionary without integer approximations. This results in a significant reduction of the estimation normalized mean squared error with reasonable computational complexity.

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BibTeXRIS

Felipe Gómez-Cuba. 2021-11-24. Compressed Sensing Channel Estimation for OTFS Modulation in Non-Integer Delay-Doppler Domain. https://arxiv.org/abs/2111.12382

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