Absorptive/Transmissive Frequency Selective Surface With Wide Absorption Band

Qingxin Guo,Lamar Y Yang,Jianxun Su,Jiming Song,Zengrui Li

doi:10.1109/access.2019.2927658

Abstract

An absorptive/transmissive frequency selective surface (ATFSS) with absorption bands at both sides of a passband is presented. Equivalent circuits of the ATFSS that consists of a lossy frequency selective surface (FSS) and a lossless FSS were modeled. To improve the rejection at an undesired band, a transmission zero was introduced and controlled by loading the lossless FSS with four-legged loaded slots. The parasitic passband was suppressed when the cross structure in the lossless FSS was loaded with resistance. In order to expand the absorption band, loaded dipoles were utilized for the lossy FSS design. An ATFSS with wide absorption bands was realized after three ATFSSs with different performances were investigated. The proposed ATFSS was fabricated and measured. The measurement results showed that a passband at around 5 GHz with a minimum insertion loss of 0.92 dB was obtained. Within an ultrawide band from 2.8 to 11.4 GHz with |S 11 | <; -10 dB, the absorption rates of higher than 80% were obtained at a lower absorption band, from 2.7 to 3.8 GHz, and at a higher absorption band, from 6.2 to 11.7 GHz. Our results showed good agreements between the measurements and simulations.

Highlights

Absorptive/transmissive frequency selective surface (ATFSS), which exhibits the characteristics of being transparent to incident electromagnetic waves in certain passbands and absorptive outside of the passbands, has attracted growing attentions during recent years
It is often referred to as a frequency selective rasorber (FSR) [1], which is a combination of the words radome and absorber, because it can be regarded as a radar absorber with transparent windows
This paper presents an ATFSS with a transparent window between two absorption bands based on the design of cascading of an absorber and a filter

Summary

INTRODUCTION

Absorptive/transmissive frequency selective surface (ATFSS), which exhibits the characteristics of being transparent to incident electromagnetic waves in certain passbands and absorptive outside of the passbands, has attracted growing attentions during recent years. The filter is transparent to the incident wave in a certain band while reflecting at the other frequencies for which it acts as a ground plane. Universal designs of an ATFSS which use two or three layers of a frequency selective surface (FSS) with certain spacing between them have been reported in some literatures. The filter for most of the presented two-layer ATFSS was designed with slot elements. This paper presents an ATFSS with a transparent window between two absorption bands based on the design of cascading of an absorber and a filter. Four-legged loaded elements and square slots were used in the design of the absorber and the filter. A passband at around 5 GHz was obtained between a lower absorption band from 2.7 to 3.8 GHz and a higher absorption band from 6.2 to 11.7 GHz

STRUCTURE AND SIMULATION RESULTS

Findings

CONCLUSION