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arXiv · 2502.05853

Zak-Transform-Induced Optimal Sequences and Their Applications in OTFS

Xiuping Peng·Congying Wu·Zilong Liu·Chunlei Li·Jianye Zhang·Xiangjun Li·Pingzhi Fan
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Abstract

This paper introduces a novel finite Zak transform (FZT)-aided framework for constructing multiple zero-correlation zone (ZCZ) sequence sets with optimal correlation properties. Specifically, each sequence is perfect with zero auto-correlation sidelobes, each ZCZ sequence set meets the Tang-Fan-Matsufuji bound with equality, and the maximum inter-set cross-correlation of multiple sequence sets meets the Sarwate bound with equality. Our study shows that these sequences can be sparsely expressed in the Zak domain through properly selected index and phase matrices. Particularly, it is found that the maximum inter-set cross-correlation beats the Sarwate bound if every index matrix is a circular Florentine array. Several construction methods of multiple ZCZ sequence sets are proposed, demonstrating both the optimality and high flexibility. {Additionally, it is shown that excellent synchronization performance can be achieved by the proposed sequences in orthogonal-time-frequency-space (OTFS) systems.

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Xiuping Peng, Congying Wu, Zilong Liu, Chunlei Li, Jianye Zhang, Xiangjun Li, Pingzhi Fan. 2025-02-09. Zak-Transform-Induced Optimal Sequences and Their Applications in OTFS. https://arxiv.org/abs/2502.05853

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