Periodic frequency selective surface coupled highly efficient, broadband, single layer microwave absorber

Abstract

Microwave absorbing materials and structures have been widelyutilized in aeronautic applications and platform. Improving the working absorption bandwidth oftraditional microwave absorbing materials (MAMs) has greatly challenged the scientists due to the restriction ofthe available material parameters. Therefore, in this paper an attempt has been made to develop a broadband absorber using synthesized ferrite nanocomposite and periodic frequency selective surface (FSS) in X-band frequency range. The effect of two different kinds of substrates (i.e., conventional FR4 and synthesized ferrite nanocomposite) has been studied over microwave absorption characteristics of FSS loaded composite structures. The significant enhancement has been observed in -10 dB absorption bandwidth after impacting of FSS over the substrate. The use of ferrite substrate results in superior absorption properties as compared to FR4 substrate. A2.55 mm thick synthesized ferrite substrate loaded with square loop FSS, provides a minimum reflection coefficient (RC) of-43.2 dB at 9.9 GHz with corresponding bandwidth of3.7 GHz. The finding reveals a flexible and promising strategyto improve the -10 dB absorption bandwidth of existing MAMs.