Effects of the troposphere upon radio communications and implications for weather measurement

Abstract

The aim of this research is to use observations of Very High Frequency (VHF) radio wave propagation to estimate the refractive index of air over a propagation path and subsequently the pressure, temperature, and water vapour. This can be accomplished by transmitting a known signal from one spatial location to another, and accurately timing the signal. The research develops methods for accomplishing the required measurements by means of a passive bistatic radar setup with a cooperative target. Such an approach overcomes the timing problems that are normally associated with propagation measurements. A network of these measurements can then be assimilated into a numerical weather prediction model, such as that used by the Australia Bureau of Meteorology, to increase weather forecast capability. Importantly, this research develops novel techniques to relate the propagation of radio waves from weather data. These techniques are important in their own right to identify true propagation paths.