Active Hearing Protectors and Audibility of Critical Communications

描述（由申请人提供）：听力保护设备（hpd）的用户，包括通信耳机和头盔，通常由飞机、空中和地勤人员、军事人员、紧急救援人员以及在嘈杂环境中工作的工业、采矿和建筑人员佩戴，长期以来一直抱怨hpd干扰了他们的通信和听到警告信号的能力。主动噪声控制技术结合信号处理技术应用于HPD内建的通信信道是一种潜在的解决方案。这种组合可以改善低频降噪，提高通信通道再现的语音清晰度，同时保持整体降噪在职业暴露要求内，并在HPD外感知到警告声音。为实现上述目标，本文提出了一种基于微型耳机和麦克风的主动环耳耳罩，并对信号进行独立的频段处理。考虑了不同程度的信号处理复杂度，以优化语音信噪比，减少屏蔽向上扩散的影响。在“原理证明”的演示之前，要建立基于主体（主观）和基于仪器（客观）的指标，以确定主动和被动降噪、语音可理解性和警告声音的感知（仅限主观方法）。客观指标，在主观测量所需时间的一小部分内提供近似结果，在器械开发期间作为相应主观指标的替代品。听力保护装置的使用者，包括飞机、空中和地勤人员、军事人员、紧急救援人员以及在嘈杂环境中工作的工业、采矿和建筑人员通常佩戴的通信耳机和头盔，长期以来一直抱怨听力保护装置干扰了他们的通信和听到警告信号的能力。提出了一种专门设计的HPD的“原理证明”研究，旨在：1)提高内置通信信道的语音清晰度；2)保持对HPD外部报警信号的感知；3)保持环境噪声的衰减。

DESCRIPTION (provided by applicant): Users of hearing protection devices (HPDs), including the communication headsets and helmets commonly worn by aircraft air and ground crews, military personnel, and emergency responders, and persons in industry, mining and construction working in noisy environments, have long complained that HPDs interfere with their ability to communicate and to hear warning signals. The technology of active noise control together with signal processing applied to a communication channel built into the HPD is proposed as a potential solution. The combination could improve noise reduction at low frequencies and enhance the intelligibility of speech reproduced by the communication channel, while maintaining the overall noise reduction within occupational exposure requirements and the perception of an warning sound outside the HPD. Research to achieve these goals is proposed based on an active circumaural earmuff equipped with miniature earphones and microphones, and independent frequency bands of signal processing. Various levels of signal processing complexity are considered to optimize the speech signal-to-noise ratio, and reduce the influence of the upward spread of masking. The demonstration of "proof of principle" is preceeded by the establishment of subject based (subjective) and instrument based (objective) metrics for determining active and passive noise reduction, speech intelligibility, and the perception of warning sounds (subjective method only). The objective metrics, which provide approximate results in a fraction of the time required for subjective measurements, are to serve as surrogates for the corresponding subjective metrics during device development. Users of hearing protection devices (HPDs), including the communication headsets and helmets commonly worn by aircraft air and ground crews, military personnel, and emergency responders, and persons in industry, mining and construction working in noisy environments, have long complained that HPDs interfere with their ability to communicate and to hear warning signals. Research is proposed to demonstrate "proof of principle" of a specialized HPD designed specifically to: 1) improve speech intelligibility of a built-in communication channel; 2) maintain the perception of alarm signals external to the HPD, and; 3) maintain attenuation of environmental noise.