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arXiv · 2501.19142

An Integrated Sensing and Communications System Based on Affine Frequency Division Multiplexing

Yuanhan Ni·Peng Yuan·Qin Huang·Fan Liu·Zulin Wang
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Abstract

This paper proposes an integrated sensing and communications (ISAC) system based on affine frequency division multiplexing (AFDM) waveform. To this end, a metric set is designed according to not only the maximum tolerable delay/Doppler, but also the weighted spectral efficiency as well as the outage/error probability of sensing and communications. This enables the analytical investigation of the performance trade-offs of AFDM-ISAC system using the derived analytical relation among metrics and AFDM waveform parameters. Moreover, by revealing that delay and the integral/fractional parts of normalized Doppler can be decoupled in the affine Fourier transform-Doppler domain, an efficient estimation method is proposed for our AFDM-ISAC system, whose unambiguous Doppler can break through the limitation of subcarrier spacing. Theoretical analyses and numerical results verify that our proposed AFDM-ISAC system may significantly enlarge unambiguous delay/Doppler while possessing good spectral efficiency and peak-to-sidelobe level ratio in high-mobility scenarios.

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Yuanhan Ni, Peng Yuan, Qin Huang, Fan Liu, Zulin Wang. 2025-01-31. An Integrated Sensing and Communications System Based on Affine Frequency Division Multiplexing. https://arxiv.org/abs/2501.19142

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