System Concepts and Algorithms for Radar Distance Measurements with Micrometer Precision

To achieve radar measurements with micrometer precision is very challenging. As a fundamental radar limitation, the range resolution is directly determined by the used radar bandwidth. Therefore, a sufficient bandwidth is needed to distinguish the wanted target from disturbing reflections, which demands wideband circuit and system concepts. Furthermore, a sophisticated calibration of RF and IF path of the radar sensor is needed as well as model-based compensation of near-field scattering effects. Finally, it is mandatory to compensate all wave propagation effects caused by humidity, pressure and temperature in order to achieve this precision. All these different aspects will be discussed and presented and finally, radar distance measurements with micrometer precision will be shown to prove the theory.