Extracting analogue signals from noise using a digital computer

Abstract

It is frequently convenient in data processing to convert analogue to digital data for computer assimilation. A convenient method of such conversion has been developed and used in the study of correlation detection of audio signals corrupted by noise. A method to use apriori knowledge of the corrupting noise to increase processing gain has been studied. In the case of detection of a sinusoid in noise, an additional gain over conventional auto -correlation of up to 14. 5 db has been achieved. Finally, a signal source located in an unknown random noise field was detected, classified and located in relative bearing by the cross-correlation of the signals received from two spatially separated sensors.