부산대학교 도서관

The use of Signals of Opportunity (SoOp) is an advantageous way to sense the Earth and ocean surface in a passive bi-static radar configuration, as it allows for smaller sensors compared to active radars. The signals transmitted by the navigation satellites (GNSS) are a good example of SoOP. Several missions using GNSS signals have been launched, e.g. . Using GNSS reflectometry it is possible to obtain estimates of ocean roughness, cryosphere, inland waters or soil moisture, e.g. Other missions using GNSS signals are also being prepared, as for instance, ESA’s second Scout Mission, HydroGNSS [9], which is targeting soil moisture, or ESA’s Pretty mission devoted to altimetry.