Towards Precise Channel Knowledge Map: Exploiting Environmental Information from 2D Visuals to 3D Point Clouds

Yancheng Wang; Chuan Huang; Songyang Zhang; Guanying Chen; Wei Guo; Shenglun Lan; Lexi Xu; Xinzhou Cheng; Xiongyan Tang; Shuguang Cui

arXiv · 2510.08140

Towards Precise Channel Knowledge Map: Exploiting Environmental Information from 2D Visuals to 3D Point Clouds

Yancheng Wang·Chuan Huang·Songyang Zhang·Guanying Chen·Wei Guo·Shenglun Lan·Lexi Xu·Xinzhou Cheng·Xiongyan Tang·Shuguang Cui

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Abstract

The substantial communication resources consumed by conventional pilot-based channel sounding impose an unsustainable overhead, presenting a critical scalability challenge for the future 6G networks characterized by massive channel dimensions, ultra-wide bandwidth, and dense user deployments. As a generalization of radio map, channel knowledge map (CKM) offers a paradigm shift, enabling access to location-tagged channel information without exhaustive measurements. To fully utilize the power of CKM, this work highlights the necessity of leveraging three-dimensional (3D) environmental information, beyond conventional two-dimensional (2D) visual representations, to construct high-precision CKMs. Specifically, we present a novel framework that integrates 3D point clouds into CKM construction through a hybrid model- and data-driven approach, with extensive case studies in real-world scenarios. The experimental results demonstrate the potential for constructing precise CKMs based on 3D environments enhanced with semantic understanding, together with their applications in the next-generation wireless communications. We also release a real-world dataset of measured channel paired with high-resolution 3D environmental data to support future research and validation.

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BibTeX RIS

Yancheng Wang, Chuan Huang, Songyang Zhang, Guanying Chen, Wei Guo, Shenglun Lan, Lexi Xu, Xinzhou Cheng, Xiongyan Tang, Shuguang Cui. 2025-10-09. Towards Precise Channel Knowledge Map: Exploiting Environmental Information from 2D Visuals to 3D Point Clouds. https://arxiv.org/abs/2510.08140

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