# Numerical Analysis and Design of an Ultra-Thin Flexible Transparent Metasurface for Broadband Radar-Infrared Compatible Stealth

## TL;DR

This paper introduces a new ultra-thin, flexible, and transparent metasurface that can help reduce radar and infrared detection, making it useful for stealth technology.

## Contribution

The novel contribution is a broadband radar-infrared compatible metasurface with ultra-thin, flexible, and transparent properties.

## Key findings

- The metasurface achieves 90% absorption in the 10.8–40.8 GHz range, covering common radar bands.
- It maintains low infrared emissivity of 0.33 and high microwave absorption in an ultra-thin 2.65 mm structure.
- The design is polarization-insensitive and reduces radar cross-section by over 10 dB even when bent.

## Abstract

In response to the significant challenges posed by the rapid progress of multi-spectral detection technologies to traditional stealth techniques, this paper presents a flexible transparent metasurface structure that is compatible with radar and infrared stealth. It consists of multi-layer functional patterned indium tin oxide (ITO) films and a flexible polydimethylsiloxane (PDMS) substrate. The metasurface uses a high-duty-cycle multi-scale circular ring to achieve a microwave absorption bandwidth of 30 GHz and low infrared emissivity of 0.33 in an optimized ultra-thin 2.65 mm thickness system. The simulation results show that the metasurface achieves absorption exceeding 90% in the frequency range of 10.8–40.8 GHz, which covers common radar bands like X, Ku, K, and Ka. Furthermore, the structure exhibits polarization insensitivity and sustains stable absorption in a wide range of 60 degrees of transverse magnetic (TM) fields. Meanwhile, it decreases the radar cross-section (RCS) by more than 10 dB over a wide angular range even when bent. This study presents a feasible metasurface with ultra-thin, flexible, transparent, and multi-spectral compatibility for the next generation of stealth systems.