Ultra-wideband RCS reduction based on coupling effects between beam diffuse and absorptive structures

Area of Science:

• Electromagnetics and Metamaterials
• Advanced Materials Science
• Radar Technology

Background:

• Traditional radar cross section (RCS) reduction techniques often face limitations in achieving broadband performance.
• Existing diffuse and absorptive methods have inherent bandwidth constraints.
• Metasurfaces offer promising avenues for tailored electromagnetic wave manipulation.

Purpose of the Study:

• To propose and demonstrate a hybrid design method for ultra-wideband RCS reduction.
• To investigate the synergistic effects between diffuse and absorptive structures in a metasurface.
• To achieve significant RCS reduction over a broad frequency range with a lightweight design.

Main Methods:

• A one-bit diffuse coding metasurface (CM) utilizing a two-layer resistive frequency selective surface (RFSS) was designed.
• The method leverages coupling effects between metallic patterns and RFSS for enhanced absorption and diffusion.
• Fabrication, analysis, simulation, and measurement of a lightweight CM loaded with RFSS were performed.

Main Results:

• The hybrid metasurface achieved a 10 dB RCS reduction in an ultra-wideband from 7.3 to 44.2 GHz (143.3% fractional bandwidth).
• The proposed mechanism effectively breaks traditional bandwidth limitations of diffusion and absorption methods.
• The metasurface demonstrated robust performance under wide-angle oblique incidences.

Conclusions:

• The developed hybrid metasurface design offers a viable solution for ultra-wideband RCS reduction.
• The coupling effect between diffuse and absorptive elements is crucial for broadening the operational bandwidth.
• This lightweight design provides a new strategy for enhancing frequency band coverage in electromagnetic wave manipulation applications.