Polarization insensitive multilayered broadband absorber for L and S bands of the radar spectrum

摘要

Designing a low frequency broadband absorber is a nontrivial task in terms of establishing a trade-off between overall absorber thickness, wide absorption bandwidth, and miniaturized unit cell size. To address the issue, we propose a novel broadband absorber design based on multilayered configuration, which covers the lower bands of the radar spectrum. The design is implemented using resistive ink patterns that are printed on an economical FR4 substrate. The reflectivity response of the proposed broadband absorber is less than -10 dB in the frequency range 1.26 to 4.38 GHz, covering the L and S bands of the radar spectrum with a fractional bandwidth of 110.63%. Furthermore, the structure has a miniaturized unit cell of dimension 0.057 lambda(L) and a notable small thickness of 0.079 lambda(L). The implementation of the equivalent circuit model further validates the proposed design. The design is fabricated and experimentally verified. The simulation and measured results are in good congruence with each other.