GNSS-based multistatic SAR

Synthetic aperture radar (SAR) is an efficient tool in remote sensing for imaging the Earth’s surface to detect, monitor, and assess its changes. Despite SAR is widely used worldwide, its operation mainly uses monostatic and bistatic configuration. In contrast, multistatic configuration is confined to simulation level, at least in open literature. This thesis experimentally explored the potential of passive multistatic SAR imaging using Global Navigation Satellite Systems (GNSS) as transmitters of opportunity and a single stationary receiver on the ground, and established a practical framework for GNSS-based multistatic SAR. During the experiment, a passive SAR system recorded satellite signal reflections off a target area from four GNSS satellites and processed these signals into bistatic images. Those images were combined using both coherent and non-coherent combination techniques to form multistatic imagery. The obtained results showed that the non-coherent multistatic method enhanced information space and revealed object geometric features such as edges, shapes, and dimensions. In addition, variations of bistatic scattering obtained from individual images can be used to coarsely classify different object types. The results also confirmed that a coherent combination of SAR images with such a system was possible and improved spatial resolution as well as power budget