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arXiv · 2306.07765

Affine Frequency Division Multiplexing For Communications on Sparse Time-Varying Channels

Wissal Benzine·Ali Bemani·Nassar Ksairi·Dirk Slock
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Abstract

This paper addresses channel estimation for linear time-varying (LTV) wireless propagation links under the assumption of double sparsity i.e., sparsity in both the delay and the Doppler domains. Affine frequency division multiplexing (AFDM), a recently proposed waveform, is shown to be optimal (in a sense that we make explicit) for this problem. With both mathematical analysis and numerical results, the minimal pilot and guard overhead needed for achieving a target mean squared error (MSE) while performing channel estimation is shown to be the smallest when AFDM is employed instead of both conventional and recently proposed waveforms.

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Wissal Benzine, Ali Bemani, Nassar Ksairi, Dirk Slock. 2023-06-13. Affine Frequency Division Multiplexing For Communications on Sparse Time-Varying Channels. https://arxiv.org/abs/2306.07765

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