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arXiv · 2604.26778

Input Distribution Design for Ranging-Oriented OFDM-ISAC Systems Under Frequency-Selective Fading

Weijiang Zhao·Yifeng Xiong
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Abstract

The implementation of the \ac{isac} feature in \ac{6g} networks is most likely to be based on the framework of \ac{ofdm}. Input distribution design, or constellation design, is a crucial technique in \ac{ofdm}-\ac{isac} systems enabling a favorable balance between communication rate and sensing performance. In this treatise, we propose a computationally efficient input distribution design approach for \ac{ofdm}-\ac{isac} under frequency-selective channels, following the theoretical framework of capacity distortion. We highlight that under practical sensing constraints, the optimal strategy is to treat the kurtosis of constellations as a resource, and allocate it appropriately over subcarriers.

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Weijiang Zhao, Yifeng Xiong. 2026-04-29. Input Distribution Design for Ranging-Oriented OFDM-ISAC Systems Under Frequency-Selective Fading. https://arxiv.org/abs/2604.26778

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