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arXiv · 2603.25623

Neural Surface and Reflectance Modelling from 3D Radar Data

Judith Treffler·Vladimír Kubelka·Henrik Andreasson·Martin Magnusson
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Abstract

Robust scene representation is essential for autonomous systems to safely operate in challenging low-visibility environments. In these conditions, radar has a clear advantage over cameras and lidars due to its resilience to environmental factors such as fog, smoke, or dust. However, radar data is inherently sparse and noisy, making reliable 3D surface reconstruction challenging. To address this, we propose a neural implicit approach for 3D mapping from radar point clouds that jointly models scene geometry and view-dependent radar intensities. Our method leverages a memory-efficient hybrid feature encoding to learn a continuous Signed Distance Field (SDF) for surface reconstruction, while also capturing radar-specific reflective properties. We show that our approach produces smoother, more accurate 3D surface reconstructions compared to existing lidar-based reconstruction methods applied to radar data and can reconstruct view-dependent radar intensities. We also show that, in general, as input point clouds get sparser, neural implicit representations render more faithful surfaces than traditional explicit SDFs and meshing techniques.

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Judith Treffler, Vladimír Kubelka, Henrik Andreasson, Martin Magnusson. 2026-07-20. Neural Surface and Reflectance Modelling from 3D Radar Data. https://arxiv.org/abs/2603.25623

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