Traditionally, direct GPS signals are used for navigation and positioning, while the indirect reflected signals are considered a nuisance. However, recent studies show that indirect reflected signals contain some useful scientific data. GPS reflected signals introduce a new and exciting way of doing ocean and land remote sensing, and have even more advantages over traditional remote sensing tools.
This project discusses the basic principles and theory of this new technology, and concentrates on reflection points and Fresnel zones. The GPS receivers are placed at different coastal regions within South Africa, and the simulation of the reflection points and Fresnel zones are observed as the GPS satellites pass over South Africa. The East London area was chosen as the location to place the receiver throughout my analysis. Areas of the Fresnel zones reaching a maximum of about 6500 km2 were observed at different receiver heights and the software to make these simulations was written using the IDL language.
Results shows that this new tool of remote sensing is feasible and has potential to be used in South Africa. The uses for this new tool include ocean altimetry, ocean, land, ice sheet remote sensing etc.