Flexible Frequency Selective Surface in Convoluted Square Form With Microstrip Patch for X-Band Application

Abstract

This article reports a very efficient Frequency Selective Surface (FSS) with Convoluted Square Loop (CSL) shape is designed for applications in the X-band. They are designed on the surfaces of an FR-4 substrate. Frequency selective surface (FSS) is a combination of a periodic structure designed to selectively absorb, reflect, and transmit electromagnetic (EM) waves. FR-4 material provides durability and flexibility. A convoluted square loop structure reduces the size of the unit cell, and it also has a better stability with good gain. So, a CSL patch with a CSL FSS array with a slot on dual FR4 substrates is introduced for the improvement in overall gain and bandwidth. As per the design parameters, a structure is designed at 10 GHz. This structure is designed with ANSYS HFSS. The proposed antenna structure has a return loss of −36.424 dB, and VSWR value is 1.0307. The measurement results show a gain improvement of 6.266 dB and bandwidth of 5.882 dB.