Accession Number : AD0877702

Title :   Spectral Analyses of Direction of Arrival of High Frequency Radio Signals.

Descriptive Note : Technical rept. no. 19,

Corporate Author : ILLINOIS UNIV AT URBANA RADIO RESEARCH LAB

Personal Author(s) : Kabele, William C. ; Bailey, A. D.

Report Date : SEP 1970

Pagination or Media Count : 71

Abstract : A time series of rapidly sampled (almost continuous) angle of arrival data obtained by two different methods on a large aperture CDAA are analyzed for spectral content using Fourier methods. The sampling rate was fast enough that spectral components as high as 0.1 Hertz could be found if present. The results are shown as CALCOMP plots of amplitude of spectral content vs. frequency. In addition to diurnal and quasi-twenty-minute period components the analyses show periods of two, five, and eight minutes. Also indicated in certain data are shorter periods of 60, 48, 22.5, 18, and 14.5 seconds, respectively. There appear to be some significant differences between the spectral content as measured by the two methods. (Author)

Descriptors :   (*DIRECTION FINDING, RADIO TRANSMISSION), (*RADIO SIGNALS, HIGH FREQUENCY), (*IONOSPHERIC PROPAGATION, ANGLE OF ARRIVAL), RADIO WAVES, ATTENUATION, PROPAGATION, AZIMUTH, FOURIER ANALYSIS, SERIES(MATHEMATICS), DIURNAL VARIATIONS, ANTENNA ARRAYS, ALGORITHMS, DIGITAL COMPUTERS, COMPUTER PROGRAMS, SPECTRUM ANALYZERS, HARMONIC ANALYSIS.

Subject Categories : Direction Finding
      Radiofrequency Wave Propagation
      Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE