EMT Conversion of Composite Broadband Absorbent Metamaterials for Stealth Application Over X-Bands

A validating approach for electromagnetic thermal (EMT) conversion of a composite broadband absorbent metamaterials (AMs) is proposed in this paper. The integrated multilayer AMs consisting of top square loop (Q-loops) array layer, middle metal plate-polymer sandwich, bottom Q-loops array layer stacked vertically is analyzed with finite-different time-domain (FDTD) algorithm and fabricated by High Density Interconnector (HDI) process and Micro-electromechanical Systems (MEMS) technology. The implemented composite layered structure with the dielectrics and subsequent multi metal loops has broadband bandwidth over 2.5GHz in X-bands. High absorption performance in various incident waves with different polarizations and incident angles basically maintains a fixed efficient level of the AMs with diverse absorbing states in wide operating band. Electromagnetics and thermal multiphysics analysis validates the EMT conversion of the AMs in induced strong electromagnetic resonance. The integrated thermal conduction device is loaded on the back of AMs to transfer the converted thermal energy in time, which effectively reduces the surface thermal distribution. Finally, absorbent properties tested by free space methods and thermocouple and infrared thermal imaging (ITI) system shows the polarization independent energy transformation in greatly accordance with numerical analysis. This investigation shows the potential application of AMs in stealth systems to achieve both electromagnetic stealth and infrared thermal stealth through EMT energy conversion.