Accession Number : ADP006170

Title :   Assessment of Anomalous Propagation Predictions Using Minisonde Refractivity Data and the Parabolic Equation Method,

Corporate Author : RUTHERFORD AND APPLETON LABS CHILTON (UNITED KINGDOM)

Personal Author(s) : Levy, M. F. ; Craig, K. H.

Report Date : SEP 1989

Pagination or Media Count : 12

Abstract : Accurate and easy-to-use systems are now available to measure the refractive index structure in the troposphere. Combined with an efficient package for solving Maxwell's equations for radiowave propagation based on the Parabolic Equation Method, they provide a powerful tool for real time forecasts of anomalous propagation. Quantitative field-strength predictions can be obtained in a few minutes from measured meteorological profiles, on a desk-top computer. However, measurement errors inevitably lead to variability in the predictions, which should be seen in a stochastic light. Some examples based on experimental data are presented, at X-band and in the millimetre wave part of the spectrum, as well as a sensitivity analysis using statistical simulations. The Parabolic Equation Method copes well with noisy refractivity data, and the predictions are fairly insensitive to radiosonde errors.

Descriptors :   *RADIO TRANSMISSION, *RADIO WAVES, *REFRACTIVE INDEX, TROPOSPHERE, WAVE EQUATIONS, EXPERIMENTAL DATA.

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE