Design and Analysis of a Frequency Selective Surface Loaded Bioinspired Antenna in Frequency and Time Domains

The paper addresses a bioinspired printed antenna in the shape of a 'Lotus' which is further loaded with a new type of Frequency Selective Surface (FSS) structure with unit cell dimension as 0.16 lambda(0) x 0.16 lambda(0) x 0.033 lambda(0), where lambda(0) is the lowest operating wavelength. The two dissimilar layers of FSS, which are separated by an air gap of about 3.2 mm, have been placed below the antenna. The combined structure operates over 3.8 GHz to 14.4 GHz (116.5% measured) with peak realized gain of 7.5 dBi. The introduction of the FSS layer provides gain enhancement of about 5.9 dBi. The stand-alone FSS geometry provides a wide transmission bandwidth from 5.5 to 12.5 GHz along with good angular stability of about 50 degrees. The Gielis superformula has been used to develop the petal of the lotus shaped antenna. The time domain analysis of the lotus shaped antenna has also been provided. The proposed structure can be used as an electromagnetic sensor for wide band applications over C, X, and partially Ku bands.