Novel circular fractal antenna array

Abstract

Traditional antennas work well only for one resonant frequency and using multiple antennas for different frequencies is a complex task, therefore multiband circular fractal antenna was designed which have a small size and multiple resonating frequencies for UltraWideband Applications (UWB). For designing and fabrication of the antenna the substrate used is FR4 which have dielectric constant 4.4 and whose dimensions are 48 96mm2. For the excitation of the antenna microstrip feed line of 50W is fed to the circular fractal patch for impedance matching. The UWB characteristics can be achieved using fractal concept. Also to increase the bandwidth, slots of different dimensions are etched out from the ground plane from the basic fractal configuration. Slots dimensions are adjusted in each iteration to achieve the desired results. In the later part of the work, different array configurations of the circular fractal antenna are analyzed. The various arrays design configurations are 1 2, 1 4, 2 2 and 2 4. The substrate used is FR4 whose dimension is varied according to the array configurations. Similar to basic antenna design a 50W microstrip feedline is used to excite the antenna for all the configurations. The antenna shows stable radiation patterns and good return loss values i.e better than 10dB at multiple frequencies. All the analysis is done in HFSS 2014.