Frequency-selective absorptive structure with wideband transmission using modal interaction pole

A dual-polarized frequency-selective absorptive structure with a wide transmission band is presented in this article. The passband is achieved by employing the modal interaction pole of the lossy array, and the multiresonant operating modes are discussed. By combining with the lossless square array, the desired transmission and absorption behaviors are obtained. Due to the modal interaction pole, the current on the lossy layer is effectively reduced, and a wide passband with high transmittance is generated. The -3 dB fractional pass bandwidth is 47.8% with a minimum insertion loss of 0.17 dB. Furthermore, a wide absorption band is achieved by employing the three resonances of the lossy array, and the absorptivity is above 99% from 5.5 to 6.5 GHz. Only four resistors are loaded on the edges of the lossy array to provide the absorption performance at the stopband. Finally, a good agreement between the simulation and measurement results validates the presented design.