Fractal Modified

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He et al.[12] have proposed a fractal high impedance topologies and effective bridges and employed for ultra-wideband (UWB) ground bounce noise (GBN) suppression in power and ground plane pairs. The 49 dB suppression bandwidth of the first design can be broadened from 202MHz to 20GHz. Raj Kumar et al.[13] have proposed the multiple bands and wider bandwidth surface wave suppression in the stopband uaing an EBG structure design based on fractal geometry. As the iteration number increases, the size of EBG structure reduces because attenuation band is shifted toward lower frequency side. The two iterative EBG structures offer the two wide bands for surface wave attenuation. The bandwidth of 1st iterative EBG is 1.64 GHz and the bandwidths of 2nd iterative EBG of two bands are 0.91 and 2.5 GHz, respectively. The antenna designed over EBG structure, patch and EBG in same plane offer improvement in bandwidth by 7.75 and 20.5%, respectively, in comparison to simple patch.Ruiz et al.[14] periodic patterns based on Koch fractal geometries have been applied to 1-D electromagnetic bandgap (EBG) microstrip structures. The Koch fractal geometries allow conceiving 1-D Koch fractal electromagnetic band-gap (KFEBG) microstrip structures with radius-to-period r/a ratios higher than 0.5, which is the upper limit of the conventional 1-D EBG microstrip structure. As a result of exceeding this limit, the 1-D KFEBG microstrip structure achieves wide band-gap frequency characteristics.Sujatha and Vinoy[15]have proposed PDEBG surface which makes use of square patches with fractal boundaries to control the phase difference. By suitably choosing fractal parameters for the patch boundary, a phase difference of 180 degree can be achieved and this can therefore be used in many specialized applications. Phuong et al.[17] have designed a Sierpinski gasket triangles, which are arranged to repeat 60 to form the hexagonal EBG unit cell and proposed two EBG structures, which have broadband and dual bandgap by setting the value of the gap between two adjacent Sierpinski inside the unit cell is equal to 0mm and greater than 0 mm, respectively.Rahman et al.[18] have studied the effects of bending on different paper-based antennas - conventional patch antenna, antenna using rectangular EBG, circular EBG designed to operate at10.15GHz using photo paper and observed that antennas bending under any conditions will cause the resonant frequency of the narrow band antennas to shift as well as mismatch degradation. For the wideband antenna, the resonant frequency shift is less severe due to the wideband characteristics.