A Co-Polarization Broadband Radar Absorber for RCS Reduction

Abstract

In this article, a single layer co-polarization broadband radar absorber is presented. Under normal incidence, it achieves at least 90% of absorption from 5.6 GHz to 9.1 GHz for both Transverse Electric (TE) and Transverse Magnetic (TM) polarizations. Our contribution and the challenge of this work is to achieve broadband absorption using a very thin single layer dielectric and it is achieved by rotating the resonating element by 45°. An original optimized Underlined U shape has been developed for the resonating element which provides a broadband co-polarization absorption. The structure is 12.7 times thinner than the wavelength at the center frequency. To understand the absorption mechanism, the transmission line model of an absorber and the three near unity absorption peaks at 5.87 GHz, 7.16 GHz and 8.82 GHz have been used to study the electric and magnetic fields. The physical insight of how the three near unity absorption peaks are achieved has also been discussed. After fabricating the structure, the measurements were found to be in good agreement with the simulation results. Furthermore, with the proposed original UUSR resonating element, the operational bandwidth to thickness ratio of 6.43 is obtained making the proposed UUSR very competitive.

Design and simulation of cross-block structured radar absorbing metamaterial based on carbonyl iron powder composite

“…Effective permeability μ can be obtained by replacing with μ in equation 3. The operational bandwidth to thickness ratio that was used to describe the performance of the absorber is given by [32] Bandwith…”

“…The proposed RAMM thickness, bandwidth and operational bandwidth to thickness ratio indicated an outstanding performance towards overcoming the challenging task of having broadband and thin thickness absorber, compared to the currently published structures of its kind [27][28][29][30], [32], [34][35][36]. The below -10dB reflectivity bandwidth of 13.8 GHz for the designed RAMM is wider than the 10 GHz bandwidth obtained in [29], 13.2 GHz in [30] and 3.5 GHz in [32]. Others are 10 GHz [34], 3.13 GHz [35] and 3.18 GHz [36].…”

“…Likewise, the referenced absorbers' operational bandwidth to thickness ratio of 7.204 [29], 9.745 [30] and 6.43 [32] are smaller than that of the modeled RAMM value of 13.029. The designed RAMM thus outclassed these broadband absorbers because the larger the ratio, the better the performance of the absorber [32]. For the calculated result, reflectivity below -10dB takes place from 3.1 to 18.0 GHz.…”

Customized Inverse Design of Metamaterial Absorber Based on Target-Driven Deep Learning Method

“…Various MMAs have achieved narrowband [1] , wideband [10]- [12], or multiband absorption [13]- [15]. These novel devices have been widely used in the areas of bolometers [16], radar cross section reduction [17], imaging devices [18], EM compatibility [19], sensing [20]- [22], and EM interference shielding [23].…”

Experimental verification of multi-band metamaterial absorber with double structured layers

“…Electromagnetic (EM) metamaterials (MMs) are artificial structures consisting of periodic array, which can demonstrate the unique physical phenomena when EM wave interact with the matters, and these unique physical phenomena is usually not existed in natural materials, For example, EM cloaks [1], perfect lens [2], energy harvesting [3,4], perfect absorbers [5][6][7][8][9][10][11][12][13] et al Since the first perfect MM-based absorber (MMA) was designed and fabricated [5], MMAs have increasingly attract researchers due to their various applications including RCS reduction, sensors and wireless energy transfer [14][15][16]. In the last decades, researchers have introduced various absorbers working on different frequency band, ranging from radio waves to optical light [17][18][19][20][21][22][23][24][25].…”