Accession Number : AD0699506
Title : SIGNAL PROCESSING OF MICROWAVES SCATTERED FROM WATER.
Descriptive Note : Research rept.,
Corporate Author : CALIFORNIA UNIV BERKELEY ELECTRONICS RESEARCH LAB
Personal Author(s) : Comeau,J. ; Angelakos,D. J.
Report Date : 01 OCT 1969
Pagination or Media Count : 77
Abstract : It has been shown possible to detect low frequency sound waves in water through 8mm microwave scattering from the water surfaces. It was the purpose of this project to improve the sensitivity of signal detection by improving the signal processing method. Three steps were taken to improve on the work previously done: (1) the implementation of the Berkeley Array Processor to greatly lessen the computation time. (2) the improvement of noise-rejection by performing autocorrelation on the sample prior to fast fourier transformation. (3) the inclusion of a 30 Hz high-pass filter to remove wind noise. It was found that the implementation of these three steps did improve the sensitivity of detection by a significant margin. (Author)
Descriptors : (*UNDERWATER SOUND, DETECTION), (*ELECTROMAGNETIC WAVE REFLECTIONS, HARMONIC ANALYSIS), MICROWAVES, SCATTERING, DATA PROCESSING, CORRELATION TECHNIQUES, INTEGRAL TRANSFORMS, WIND, COMPUTER PROGRAMS
Subject Categories : Acoustics
Radiofrequency Wave Propagation
Distribution Statement : APPROVED FOR PUBLIC RELEASE