HELIUM-SPEECH COMMUNICATION

摘要

The invention relates to a novel helium-speech unscrambler which can be located at a diver's location, and enables the helium-speech voiced by the diver to be subjected to waveform time expansion of an initial portion of each pitch period to reduce the bandwidth of the helium speech (e.g. to 2 to 3 KHZ) prior to transmitting the speech signals to a distant location on a carrier wave selected for optimum transmission through the water.