A novel dual-band absorber for millimeter-wave RADAR applications

Alinearlypolarizeddual-resonantmillimeter-waveabsorberforRadioDetectionAndRanging(RADAR) applications is presented in this paper. The frequency-selective absorber (FSA) iscomposed of solitarily using the distributed elements. The proposed FSA achieves a dual-bandresonance characteristic utilizing the mutual coupling between concentric square loops, thesecond harmonic mode of the Jerusalem cross, and the corrugated cross grids. The proposeddual-bandFSAoperatesfrom25.5to26.5GHz(1GHz)(fL)and31.8GHz-32.5GHz(0.7GHz)(fH) with minimum absorptivity of 96% and 92%, respectively. The desired frequency responseof the proposed unit cell is demonstrated by an equivalent circuit model. The FSA prototypeis fabricated and the simulated results are validated using experimental measurements. Theproposed FSA is a suitable candidate for stealth application in defense and military systems.