Acoustic differential digital coder

摘要

An arrangement for directly converting speech waves into coded digital signals includes a vibratory diaphragm secured at an aperture in a closed chamber. The diaphragm vibrates responsive to the difference between the speech waves and sound waves radiated into the chamber from a digital signal to sound converter through a second aperture. Apparatus connected to the diaphragm generates a quantized signal responsive to the diaphragm motion and a digital code generator produces a sequence of digital coded signals corresponding to the quantized signals. The coded signals from the digital code generator are delayed and supplied to the sound converter whereby a differential pulse code modulated signal representative of the speech waves is produced.