INTERSUBMARINE SPEECH INTELLIGIBILITY LEVELS by

The purpose of this investigation was to determine levels of speech intelligibility between two submarines using standard transmitting and receiving units while in operation. Transmission and reception of prerecorded and live voice word lists was made using an AN/WQC-2 sonar unit with directional and omnidirectional transducer arrays. The lists were recorded at the point of reception and played back to listeners for an evaluation of the speech intelligibility. The results indicate that the intelligibility scores were highest when reception was directional and both the transmitter and receiver were at the same depth. The live voice tests showed slightly higher intelligibility scores than the prerecorded lists. It would appear that further tests on reception mode incorporating such variables as range, depth * and speed of the ships are necessary to generalize to more operating conditions than those tested in this study.