Abstract:
Global Navigation Satellite System Reflectometry (GNSS-R) is a relatively new bistatic radar remote sensing technique that uses GNSS navigation satellites like GPS and Galileo as its transmitter and provides its own receiver to measure the navigation signal after it is scattered from the Earth surface back into space. Modifications to the signal caused by the scattering process contain information about the surface properties. Those properties include near-surface wind speed over water, soil moisture, inland water boundaries, and surface height. A GNSS-R type of radar is particularly attractive because a receiver alone is much smaller, lower power and cheaper than a conventional radar that includes a transmitter. As a result, GNSS-R systems can fly on smaller satellites and constellations of them can be flown to provide more frequent global coverage. This seminar will provide an overview of the science and applications possible with a spaceborne GNSS-R system, using the NASA CYGNSS constellation of eight small satellites as an example. Numerous follow-on GNSS-R missions have either been launched or are currently in development, and these will also be discussed.