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arXiv · 2005.07900

Reconstruction of Multi-user Binary Subspace Chirps

Tefjol Pllaha·Olav Tirkkonen·Robert Calderbank
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Abstract

We consider codebooks of Complex Grassmannian Lines consisting of Binary Subspace Chirps (BSSCs) in $N = 2^m$ dimensions. BSSCs are generalizations of Binary Chirps (BCs), their entries are either fourth-roots of unity, or zero. BSSCs consist of a BC in a non-zero subspace, described by an on-off pattern. Exploring the underlying binary symplectic geometry, we provide a unified framework for BSSC reconstruction---both on-off pattern and BC identification are related to stabilizer states of the underlying Heisenberg-Weyl algebra. In a multi-user random access scenario we show feasibility of reliable reconstruction of multiple simultaneously transmitted BSSCs with low complexity.

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Tefjol Pllaha, Olav Tirkkonen, Robert Calderbank. 2020-05-16. Reconstruction of Multi-user Binary Subspace Chirps. https://arxiv.org/abs/2005.07900

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