Invisibility vs Super-visibility: Changing an Object's Visibility to Electromagnetic Waves

Abstract

Starting from the 1980s, discussions about invisible planes have been continuously popular. How to change the visibility of an object to electromagnetic waves is a significant topic and what this project digs into. The project focuses on using Huygens Metasurface to redirect the incident wave to wide angles to reduce the monostatic radar cross-section (RCS). The project is conducted with simulations of a well-designed Huygens Metasurface using Ansys HFSS as well as practical measurement of the reflection factor. In the measurement, when inputting the wave from 0 degree, the monostatic RCS of the metasurface is reduced by 16.47dB (2.25% of the input power) compared to the RCS of Perfect Electric Conductor (PEC). The two redirecting waves have the reflection factors of - 3.22dB and -3.24dB respectively (47.6% and 47.4% of the input power respectively), which can achieve a power redirecting efficiency of 95%. In conclusion, the monostatic RCS can be successfully reduced by the well-designed Huygens Metasurface. With the high efficiency of power redirection, the metasurface can be used as an RCS reducer as well as a power splitter. Besides, this metasurface can also be designed to increase RCS by redirecting the wave back to the incident angle to achieve super-visibility.