Comparison of Bone-Conduction Technologies

Abstract

Abstract : Bone-conduction technologies have been proposed for use with radio communication for the military. Three manufacturers have made commercially available bone-conduction systems that transmit and receive radio signals through bone conduction. The purpose of this study was to evaluate these three bone-conduction microphones and vibrators separately in order to determine which devices performed best in each capacity. The evaluation of the vibrators was conducted through presentation of speech items over each device while the listener was in background noise levels of 100 and 110 dB A-wtd. The vibrators from manufacturer A outperformed the others on the speech recognition task. The evaluation of microphones was conducted through a presentation over headphones of speech items that were recorded through each microphone in background noise levels of 100 and 110 dB A-wtd. There were no significant differences between the speech recognition performances with the microphones. Sound quality judgments made on paired comparisons of the microphones and vibrators indicated listener preference for the vibrators from manufacturer A but no single microphone. In order to provide the best bone conduction communication system to the Soldier, vibrators from manufacturer A should be used. The results of this study do not allow a recommendation for the best microphone.