L-Slots Fractal Antenna with DGS for Dual band Applications

This work presents the design of an ‘L’ shaped slot Fractal-based Rectangular Patch with Defective Ground Structure (DGS) for dual band operation, which makes it suitable for X-band (8-12 GHz) and K
u
-band (12-18 GHz) applications. The four L-shaped slots are considered for each iteration and 2*2 array, with equal slot area. Four asymmetric plus slots are created on the radiating patch in the centre of the elements of the 2*2 array antenna to produce circular polarization. The incorporation of DGS resulted in increased bandwidth and dual band operation. Antenna parameters are analysed to study its performance. The proposed antenna with DGS offers dual band operation with a frequency bandwidth of 1.86 GHz (10.26 GHz – 12.13 GHz) and 2.23 GHz (16 GHz – 18.23 GHz). Peak gain obtained is 7.9 dB at 16.92 GHz with DGS. The proposed antenna exhibits circular polarisation in the frequency range of 18.11-18.37 GHz. The simulations were carried out using HFSS software.