A dual‐polarized frequency‐selective absorber (FSA) with wide transmission band is proposed and designed. First, a three‐layered antenna‐filter‐antenna structure is designed to construct a wide passband. Then, a lossy resonator is introduced to achieve the absorption properties. Therefore, the resultant FSA can achieve one wide passband in higher frequencies and one absorptive band at lower frequencies, and thus can be applied as a radome of an antenna system. In the transmission band (3.51‐5.33 GHz), the signal can transmit through the absorber. Meanwhile, in the absorption band (1.67‐3.10 GHz), the coming wave is absorbed to reduce the radar cross section of the antenna. The total thickness of the FSA is less than 0.1λ L at the lowest operating frequency.

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This article presents a wideband frequency selective absorber with a high selective reflective‐band for RCS reduction application. The proposed design consists of three metallic layers. With lossy resonance of the resistors‐loaded folded loop at the front layer, wide absorption performance is obtained. Then two independently lossless resonances are employed to introducing a flexible and high selective reflective‐band with full reflectance into the absorption band. The resultant absorbers have the thickness of only ~0.076 λL at the lowest operating frequencies and exhibit a whole operating bands of 126.3%. Two absorption band with bandwidth of 60.3% and 44.5% have been achieved. A prototype of the proposed structure has been fabricated, whose measured results show reasonable agreement with the simulated responses under normal incidence.

COVID-19 started in late 2019 and Ukraine conflict started on February 24, 2022 have caused inflation and energy crises to the world. The aim of this paper is to research on the inflation and energy crisis under COVID-19 and Ukraine Conflict by analyzing three markets including the United States, Europe, and China through their reactions to the crises. This is because these three markets are three typical economic entities of the world which have features and representative. Detailed information has been acquired by the authors that the degree these three markets are influenced. Behaviors and measures taken to deal the situation would be analyzed through the relative economic data. Through comparison and analysis, the result is all these three bodies are affected at varying levels on import and export, job opportunity, industrial structure, agriculture and so on. From the study, the authors came to realize that China goes through the crisis relatively smoothly while the United States and Europe are more severely affected. Expectations of the macro situation will be introduced in the end.

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