The application of advanced digital-processing techniques has great potential for systems that transmit voice or utilize information coded in the form of speech. The report employs a digital process that offers a new approach for general use in speech synthesis, and is an application of homomorphic methods to the problem of correcting the distorted speech of talkers in pressurized helium-oxygen atmospheres. The vocal-tract impulse response of such speech was extracted by the homomorphic deconvolution technique, and its frequency components were moved downward in frequency according to correction formulas given in a study by Gerstman (1966). Both linear and nonlinear frequency corrections were used. Speech samples taken at 800-foot pressure depth in a 96 percent helium, 4 percent oxygen atmosphere were processed in this way, using a digital simulation of Oppenheim's (1969) analysis-synthesis system. Results indicate considerable promise for the technique as a tool for further study of helium speech, and perhaps as a future on-line translation method. (Author).

The application of advanced digital-processing techniques has great potential for systems that transmit voice or utilize information coded in the form of speech. The report employs a digital process that offers a new approach for general use in speech synthesis, and is an application of homomorphic methods to the problem of correcting the distorted speech of talkers in pressurized helium-oxygen atmospheres. The vocal-tract impulse response of such speech was extracted by the homomorphic deconvolution technique, and its frequency components were moved downward in frequency according to correction formulas given in a study by Gerstman (1966). Both linear and nonlinear frequency corrections were used. Speech samples taken at 800-foot pressure depth in a 96 percent helium, 4 percent oxygen atmosphere were processed in this way, using a digital simulation of Oppenheim's (1969) analysis-synthesis system. Results indicate considerable promise for the technique as a tool for further study of helium speech, and perhaps as a future on-line translation method. (Author).

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Advances in Electronics and Electron Physics