Microphone Array Signal Processing and Active Noise Control for the In-Helmet Speech Communication

Widely varying working conditions of a space shuttle and the special design of an astronaut's spacesuit form an extreme acoustic environment that imposes unique challenges for capturing and transmitting speech communications to and from a crewmember. NASA has a serious unmet need for innovative voice communication systems and technologies, which provide enhanced speech intelligibility and quality, comfort and ease of use, and adequate hearing protection. This project will build on knowledge and recent breakthroughs produced by painstaking research at Bell Labs and WeVoice, Inc., in acoustic and speech signal processing for hands-free communications. It brings together the state-of-the-art and patent-pending techniques in microphone arrays, speech enhancement, and active noise control, and proposes an integrated, more reliable solution for combating high-level noise and strong reverberation. This proof-of-feasibility research will focus primarily on whether the proposed techniques that were previously developed for applications in room acoustic environments can perform as well as or better than we expect in an in-helmet acoustic environment. In addition, this research will use informal listening tests to demonstrate performance improvement and will design a subjective program that can be readily executed in Phase II to rigorously evaluate the overall system performance. The Phase I effort will provide a foundation for prototype design to be conducted in Phase II.