This paper presents the four iterative circular shaped fractal antenna and its backscattering RCS with respect to iteration. First, the solid circular patch antenna has been designed on substrate εr = 2.2, h=0.787 mm with a = 40.766 mm and aspect ratio b/a = 0.98. The antenna has been simulated using FDTD method. The resonant frequency of this antenna has been observed at 1.42 GHz. The four iterative circular fractal antennas have also been designed with same substrate and dimension. This multi-band fractal antenna has been simulated, fabricated and tested. It has been observed experimentally that antenna is working on multiple frequencies. The size reduction of antenna is evident because first resonant frequency is shifted to 1.09 GHz in comparison to solid simple patch at 1.42 GHz. The experimental resonant frequencies of fractal antenna are 1.09 GHz, 1.65 GHz, 2.92 GHz and 4.485 GHz. The experimental and simulated resonant frequencies of antenna are in good agreement. The backscattering power with respect to iteration has been analyzed. It is observed that four iterative structure offers less backscattering power.

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Multiband Antenna Fractal Antenna Coaxial Feed Microstrip Antenna