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arXiv · 2603.10958

Distortion Is Not Noise: On the Limits of the Kappa Model for Monostatic ISAC

Haofan Dong·Ozgur B. Akan
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Abstract

Monostatic ISAC sensing differs from communication because the transmitter can monitor its distorted transmit waveform. Thus, the aggregate $\kappa$ distortion model, which treats impairments as unknown noise, is appropriate for communication but pessimistic for monostatic sensing. We derive PA-aware sensing Cram\'er--Rao bounds (CRBs) and a PN-aware CRB that reveals an irreducible velocity-error floor, and quantify when $\kappa$-based bounds overestimate sensing degradation. Simulations validate the analysis and show robustness to practical DPD template errors (less than 1~dB overhead at a typical $-25$~dB NMSE).

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Haofan Dong, Ozgur B. Akan. 2026-03-11. Distortion Is Not Noise: On the Limits of the Kappa Model for Monostatic ISAC. https://arxiv.org/abs/2603.10958

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