The widespread adoption of voice-activated systems has modified routine human-machine interaction but has also introduced new vulnerabilities. This paper investigates the susceptibility of automatic speech recognition (ASR) algorithms in these systems to interference from near-ultrasonic noise. Building upon prior research that demonstrated the ability of near-ultrasonic frequencies (16 kHz - 22 kHz) to exploit the inherent properties of microelectromechanical systems (MEMS) microphones, our study explores alternative privacy enforcement means using this interference phenomenon. We expose a critical vulnerability in the most common microphones used in modern voice-activated devices, which inadvertently demodulate near-ultrasonic frequencies into the audible spectrum, disrupting the ASR process. Through a systematic analysis of the impact of near-ultrasonic noise on various ASR systems, we demonstrate that this vulnerability is consistent across different devices and under varying conditions, such as broadcast distance and specific phoneme structures. Our findings highlight the need to develop robust countermeasures to protect voice-activated systems from malicious exploitation of this vulnerability. Furthermore, we explore the potential applications of this phenomenon in enhancing privacy by disrupting unauthorized audio recording or eavesdropping. This research underscores the importance of a comprehensive approach to securing voice-activated systems, combining technological innovation, responsible development practices, and informed policy decisions to ensure the privacy and security of users in an increasingly connected world.

翻译：语音激活系统的广泛应用改变了人机交互的日常模式，但也引入了新的脆弱性。本文研究了这些系统中自动语音识别（ASR）算法对近超声波噪声干扰的敏感性。基于先前研究表明近超声波频率（16 kHz - 22 kHz）能够利用微机电系统（MEMS）麦克风的固有特性，本研究探索了利用这一干扰现象实现替代性隐私保护手段的途径。我们揭示了现代语音激活设备中最常见麦克风存在的一个关键脆弱性——这些麦克风会无意中将近超声波频率解调到可听频谱范围内，从而干扰ASR过程。通过对近超声波噪声对多种ASR系统影响的系统分析，我们证明这种脆弱性在不同设备以及广播距离、特定音素结构等不同条件下具有一致性。研究结果凸显了开发稳健对策以保护语音激活系统免受该脆弱性恶意利用的必要性。此外，我们还探索了利用这一现象通过干扰未经授权的音频录制或窃听来增强隐私保护的潜在应用。本研究强调了构建语音激活系统综合安全方案的重要性，需要融合技术创新、负责任的开发实践和明智的政策决策，以确保用户在日益互联的世界中的隐私与安全。