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arXiv · 1910.14412

Geometric Sequence Decomposition with $k$-simplexes Transform

Woong-Hee Lee·Jong-Ho Lee·Ki Won Sung
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Abstract

This paper presents a computationally efficient technique for decomposing non-orthogonally superposed $k$ geometric sequences. The method, which is named as geometric sequence decomposition with $k$-simplexes transform (GSD-ST), is based on the concept of transforming an observed sequence to multiple $k$-simplexes in a virtual $k$-dimensional space and correlating the volumes of the transformed simplexes. Hence, GSD-ST turns the problem of decomposing $k$ geometric sequences into one of solving a $k$-th order polynomial equation. Our technique has significance for wireless communications because sampled points of a radio wave comprise a geometric sequence. This implies that GSD-ST is capable of demodulating randomly combined radio waves, thereby eliminating the effect of interference. To exemplify the potential of GSD-ST, we propose a new radio access scheme, namely non-orthogonal interference-free radio access (No-INFRA). Herein, GSD-ST enables the collision-free reception of uncoordinated access requests. Numerical results show that No-INFRA effectively resolves the colliding access requests when the interference is dominant.

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Woong-Hee Lee, Jong-Ho Lee, Ki Won Sung. 2019-10-31. Geometric Sequence Decomposition with $k$-simplexes Transform. https://doi.org/10.1109/tcomm.2020.3028876

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