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arXiv · 2407.21400

Low-Coherence Sequence Design Under PAPR Constraints

Gangle Sun·Wenjin Wang·Wei Xu·Christoph Studer
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Abstract

Low-coherence sequences with low peak-to-average power ratio (PAPR) are crucial for multi-carrier wireless communication systems and are used for pilots, spreading sequences, and so on. This letter proposes an efficient low-coherence sequence design algorithm (LOCEDA) that can generate any number of sequences of any length that satisfy user-defined PAPR constraints while supporting flexible subcarrier assignments in orthogonal frequency-division multiple access (OFDMA) systems. We first visualize the low-coherence sequence design problem under PAPR constraints as resolving collisions between hyperspheres. By iteratively adjusting the radii and positions of these hyperspheres, we effectively generate low-coherence sequences that strictly satisfy the imposed PAPR constraints. Simulation results (i) confirm that LOCEDA outperforms existing methods, (ii) demonstrate its flexibility, and (iii) highlight its potential for various applications.

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Gangle Sun, Wenjin Wang, Wei Xu, Christoph Studer. 2024-07-31. Low-Coherence Sequence Design Under PAPR Constraints. https://arxiv.org/abs/2407.21400

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