Enhancing Radar-Based Positioning with ISAR Imaging Techniques

Inertial Measurement Units (IMUs) require regular calibration updates to maintain high-precision navigation. A radar based method can be used as GNSS-free alternative. The radar either can illuminate known targets or areas on the ground or it could be used to illuminate satellites with known trajectories. But their illumination only gives a range measurement at high measurement quality. Exploiting imaging techniques give a second accurate measurement dimension along the main movement direction of the satellite, relative to the aerial vehicle. This investigation shows first ideas how this could be done including refraction, which accuracy is necessary for the satellite trajectory and presents simulation results to test for measurement accuracy.