Accession Number:

AD0274466

Title:

STUDY OF A SPEECH COMPRESSION SYSTEM (SPECTRUM SELECTION)

Descriptive Note:

Corporate Author:

BOLT BERANEK AND NEWMAN INC CAMBRIDGE MASS

Report Date:

1962-01-30

Pagination or Media Count:

1.0

Abstract:

The design for the final model of a spectrumsampling speech compression system that utilizesA BINARY DIGITALLY CODED SIGNAL DURING TRANSMISSION WAS COMPLETED. The system provides a signal having a total analog bandwidth of 750 c. This analog signal is divided into 2 separate portions prior to analog to digital conversion each portion is transposed to occupy the frequency space from 0 - 375 c. The analog input to the digital to analog converter is commutated between the 2 analog signals at a rate of about 25-c. A cycle is defined as a look at channel A, followed by a look of equal length at channel B. The analog to digital converter samples the analog signal presented at its input at a rate of 750 samples per second and quantizes the difference between successive samples into a serial binary signal. The receiver of the system converts the signal to analog form and transposes the various narrow analog bands to their proper place on the frequency scale. A digital storage register is provided in the receiver so that one portion of the signal can be reiterated to fill in intervals that are time shared with the other portion of the speech signal. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE