Broadband microwave-absorbing honeycomb structure with novel design concept

In this study, a novel broadband microwave-absorbing honeycomb structure is designed using a new concept and is fabricated. To efficiently improve the absorbing performance, the proposed novel design concept uses the transverse direction of a honeycomb structure made out of a lossy material. In that the honeycomb structure can be used in the transverse to the ribbon direction, the effective thickness in terms of the incident EM waves becomes very large, resulting in the enhancement of absorption bandwidth. The designed absorbing honeycomb structure was fabricated using glass/epoxy-MWCNT prepregs and the autoclave process. The measured absorbing performance of the fabricated absorbing honeycomb structure using a free-space measurement system satisfied −10 dB absorption from 3 GHz to 16 GHz. When the performance of the absorbing honeycomb structure is considered in terms of the absorbing bandwidth, because most tracking radars use the C band and/or the X band due to their resolutions, the verified return loss of the absorbing honeycomb structure was found to be superior. It was shown that a lightweight and broadband absorber could be implemented without the use of a magnetic material and without limitations on the thickness.