An absorptive coding metasurface for ultra-wideband radar cross-section reduction

Area of Science:

• Electromagnetics
• Materials Science
• Metamaterials

Background:

• Metasurfaces offer advanced control over electromagnetic waves.
• Radar cross section reduction is crucial for stealth applications.
• Ultra-wideband (UWB) performance presents significant design challenges.

Purpose of the Study:

• To propose and design an absorptive coding metasurface (ACM) for UWB RCS reduction.
• To investigate the performance of a lossy polarization conversion metasurface (PCM) as a building block.
• To demonstrate the ACM's effectiveness under various polarizations and incident angles.

Main Methods:

• Design of a lossy, anisotropic PCM with polarization conversion and absorption.
• Utilizing the PCM as coding elements in an ACM configuration.
• Simulation and experimental validation of the ACM's RCS reduction performance.

Main Results:

• The lossy PCM exhibits co-polarization reflection coefficients < -10 dB from 7.5 to 45.2 GHz.
• The ACM achieves effective RCS reduction from 7.4 to 45.5 GHz (6.15:1 bandwidth) at normal incidence.
• UWB RCS reduction is maintained even at a 45° incident angle.

Conclusions:

• The proposed ACM demonstrates excellent UWB RCS reduction capabilities.
• The design shows practical stealth performance against various radar bands (X, Ku, K, Ka).
• The ACM is a promising solution for enhancing the stealth of platforms.