Interferometric Imaging Radar for Space Situational Awareness Satellite Characterisation

The three-dimensional imaging of satellites from a groundbased radar is considered in a space situational awareness context. Utilizing the synthetic aperture radar (SAR) tomographic formulation and a model of the collection geometry in a specific low Earth orbit scenario, the shape and repeat nature of collection passes from ascending and descending orbits is evaluated and constraints on the formation of 3D SAR images are discussed. Processing of the three dimensional data can be implemented using interferometric and beamforming techniques. A worked example of a Ku-Band fine resolution radar systems illustrates that both interferometric and the curved collection path depth of focus information can be potentially utilized to form high fidelity three-dimensional images.