Accession Number : AD0766676

Title :   Field Test of a Near Real-Time Ionospheric Forecasting Scheme (500 km).

Descriptive Note : Research and development technical rept.,

Corporate Author : ARMY ELECTRONICS COMMAND FORT MONMOUTH N J

Personal Author(s) : Krause,George E. ; D'Accardi,Richard J. ; Roswell,Edwin L. , III

Report Date : AUG 1973

Pagination or Media Count : 65

Abstract : H FORECASTS, IN NEAR REAL-TIME, OF IONOSPHERIC CONDITIONS PERTINENT TO HF communications. To do this, vertical incidence (VI) ionospheric data was used to predict Maximum Observed Frequencies (MOF) over a 445 km path. Vertical incidence and oblique incidence (OI) maximum observed frequency data were gathered at the terminals of the path between Fort Monmouth, New Jersey, and Camp Drum, New York. A statistical analysis of the data showed the VI data to be a poor approximation to the OI data. Further, results show that using an obliquity factor based upon the secant law applied to VI data taken at an end point failed to compensate for the observed differences between OI and VI data. An obliquity function was derived, however, which did compensate for these differences. MOF forecasts based upon the model of Ames-Egan, are given for 10, 30, 60, and 120 minutes in advance. (Author)

Descriptors :   (*IONOSPHERIC PROPAGATION, RADIO INTERFERENCE), (*RADIOFREQUENCY INTERFERENCE, PREDICTIONS), RADIO TRANSMISSION, HIGH FREQUENCY, REGRESSION ANALYSIS, REAL TIME, ARMY OPERATIONS

Subject Categories : Radiofrequency Wave Propagation
      Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE