To balance venue safety with public photography rights, this paper presents CamShield _ a novel system for selective defense against unauthorized photography. Amid dense electromagnetic environments, CamShield reliably identifies cameras by analyzing their unintended electromagnetic emissions. By tracing frequency drift patterns and harmonic spectral movements unique to each device, CamShield can accurately detect cameras despite environmental noise or model similarities. An integrated antenna amplitude ratio module and Kalman filter further localize threats through resilient positioning. Directional ultrasonic beams then focus tuned acoustic interference toward devices, temporarily disrupting visualization in restricted locations while preserving ambient imaging freedoms. Comprehensive evaluations across three state-of-the-art object detectors quantify real-world reliability. With 30 intruding cameras, CamShield exhibited obstruction latencies below 346 ms. Furthermore, CamShield achieves three times the coverage using the same power as traditional Omnidirectional transmission. Together, the breakthroughs in pervasive camera sensing and context-aware actuation contribute toward advancing policy-centric access controls at the edge of cyber-physical convergence. CamShield sets an important precedent on enforcing venue custom protections in bounded secure zones without undermining positive public photography assumptions elsewhere.

中文翻译：

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CamShield：追踪电磁学以引导超声波打击非法相机


为了平衡场馆安全和公共摄影权，本文提出了 CamShield _一种选择性防御未经授权摄影的新颖系统。在密集的电磁环境中，CamShield 通过分析摄像机的意外电磁辐射来可靠地识别摄像机。通过跟踪每个设备特有的频率漂移模式和谐波频谱运动，尽管环境噪声或模型相似，CamShield 仍可以准确检测摄像机。集成天线幅度比模块和卡尔曼滤波器通过弹性定位进一步定位威胁。然后，定向超声波束将调谐的声学干扰集中到设备上，暂时扰乱受限位置的可视化，同时保留周围成像的自由度。对三个最先进的物体探测器的综合评估量化了现实世界的可靠性。对于 30 个入侵摄像机，CamShield 的阻塞延迟低于 346 毫秒。此外，CamShield 使用与传统全向传输相同的功率实现了三倍的覆盖范围。总之，普遍摄像头传感和上下文感知驱动方面的突破有助于在网络物理融合的边缘推进以策略为中心的访问控制。 CamShield 开创了一个重要先例，即在有限的安全区域内实施场馆定制保护，同时又不会破坏其他地方积极的公共摄影假设。