Speaking aid system for total laryngectomees using voice conversion of body transmitted artificial speech

The aim of this paper is to improve the naturalness of speech using a medical device such as an electrolarynx. There are several problems associated with using existing electrolarynxes, such as the fact the loud volume of the electrolarynx itself might disturb smooth interpersonal communication, and that the generated speech is unnatural. We propose a novel speaking-aid system for total laryngectomees using a new sound source as an alternative to the existing electrolarynx and a statistical voice-conversion technique. The new sound-source unit outputs extremely small signals that cannot be heard by people around the speaker. Artificial speech is recorded with a NAM microphone through soft tissues of the head. From the result of voice conversion, the body-transmitted artificial speech is consistently converted to a more natural voice. We also demonstrate that the speech recognition performance of the proposed system substantially increases in terms of objective evaluation.