Extension of High Frequency Over-the-horizon Radar Atmospheric State and Variability Studies to a Broader Range of Wavelengths and Elevations

Several significant upgrades have been incorporated into the latest version of the Core Truth Models (CTM) Environment Library. Nevertheless, significant upgrades to the pre-runtime environment modeling capability are required for the CTM implementation in ground test to add value to Radar Frequency (RF) effects component of the simulations. The radar tropospheric scintillation effect must be extended to a broader range of elevations and frequencies. The tropospheric scintillation effect can be extended by adding fluctuations due to rain rate and other RF phenomena. The CTM Environment Library RF effects models (beam bending, range delay, lens loss, and clear air attenuation) require atmospheric model inputs more realistic than average or exponential atmosphere models. Approved for Public Release | 25-MDA-12052 (27 Mar 25)