A Simple Note on Shadowing Effects and Multipath Propagation for CNS

This contribution discusses shadowing effects of large objects with respect to navigation and communication systems. Since the current practice for assessing the impact of scattering objects on those systems is based on mainly quasi-optical wave propagation, a simplified, but yet improved analysis of possible disturbances is proposed. Based on scattering theory, a simple analytic formula is derived applying fundamentals of the radar cross section concept. As for at least canonical objects, such as metal plates or cylinders, for which an accurate analytic description for the radar cross section is well known, simple shadowing examples are discussed. With the derived formula a more sophisticated sensitive area layout can be developed than it is currently recommended with an overall layout, i.e. typically a circular area with a fixed radius. Finally, measurement results in a miniaturized anechoic chamber are presented that give additional insight into the shadowing phenomena discussed in this contribution. Further, measurement results are shown as examples for travelling waves and shadowing effects.