System simulation for FMCW radar in industrial applications

The demand for high accuracy radar systems is continuously growing, especially in automation industry. Most of these systems are based on the distance measurement for single target and in many cases the measurement system consists of a guided wave structure, e.g. rectangular or cylindrical waveguides. However, in reality the resulting measurement results suffer from multiple spectral components besides the desired target spectrum, which occur due to multiple reflections in the measurement system. In this paper, a system simulation is presented that takes into account all relevant reflections in the measurement systems and enables prediction of the resulting spectra and its influence of the achievable measurement accuracy. Furthermore, the ideal measurement region within the waveguide can be determined depending on the target quality. The simulation results are verified by measurements and a range accuracy of ±5μm is shown by means of proper target design.