RF-VoID：通过窄带射频表征学习实现带宽高效的外墙瓷砖空鼓检测

中文摘要 AI 辅助

外墙瓷砖背后的隐藏脱粘是瓷砖脱落的安全隐患，毫米波雷达提供了一种非接触式的检测手段。传统处理方法首先重建距离剖面，其可靠性受限于可用带宽，而带宽恰恰决定了部署系统的成本、采集时间和监管足迹。本研究探讨能否用计算换取带宽。一套4-40 GHz步进频率系统扫描了十二个外墙试件，其中包含深度和界面不同的0.5-1.0 mm空气空隙，并分析了A扫描、B扫描和C扫描解释的带宽依赖性，以确定分辨率界限。随后提出RF-VoID，它直接基于窄带复数响应进行决策：子带保持其测量频率顺序，包含幅度和相位以及同相和正交通道，双分支编码器沿物理频率轴使用相对位置编码和距离相关的局部性偏置读取该响应，面向检测的目标函数处理类别不平衡和立面筛查的不对称错误成本。在混合样本协议下，该方法在0.5 GHz带宽下达到98.61%的准确率和95.84%的F1分数，相比全带宽扫描减少了七十二倍，且无需距离剖面重建、反卷积或深度切片选择；在完全未参与训练样本的试件上，它仍是所比较模型中最强的，在0.5 GHz时平均宏F1分数为62.12%，在1 GHz时升至68.57%。

英文摘要

Hidden debonding behind exterior ceramic tiles is a falling-tile hazard, and millimeter-wave radar offers a non-contact way to find it. Conventional interpretation first reconstructs a range profile, so its reliability is bounded by the available bandwidth, yet bandwidth is what sets the cost, the acquisition time, and the regulatory footprint of a deployed system. This work asks whether that bandwidth can be traded for computation. A 4-40 GHz stepped-frequency system scans twelve exterior-wall specimens containing 0.5-1.0 mm air voids at different depths and interfaces, and the bandwidth dependence of A-scan, B-scan, and C-scan interpretation is analyzed to establish the resolution bound. RF-VoID is then proposed, which decides directly on the narrowband complex response: the sub-band is kept in its measured frequency order with amplitude and phase alongside the in-phase and quadrature channels, a dual-branch encoder reads it along the physical frequency axis using relative position encoding and a distance-dependent locality bias, and an inspection-oriented objective handles the class imbalance and the asymmetric error cost of facade screening. Under a mixed-sample protocol the method attains 98.61% accuracy and a 95.84% F1-score with 0.5 GHz of bandwidth, a seventy-two-fold reduction relative to the full sweep, without range-profile reconstruction, deconvolution, or depth-slice selection; on specimens held out entirely from training it remains the strongest of the compared models, with a mean macro F1-score of 62.12% at 0.5 GHz that rises to 68.57% at 1 GHz.

发表机构

• MARS Lab, Nanyang Technological University, Singapore（新加坡南洋理工大学MARS实验室）
• Ibaraki University, Mito, Ibaraki, Japan（日本茨城县水户市茨城大学）
• The University of Tokyo, Bunkyo, Tokyo, Japan（日本东京都文京区东京大学）

机构由 AI 辅助整理，请以论文原文为准。