Design of Optimized Koch Based Fractal Patch Antenna for Multiband Wireless Applications

An optimized Koch based fractal patch antenna with twin lower leafs has been designed for appropriate wireless communication applications and capable of exhibiting penta-band behavior. The proposed structure has been created by introducing modified Koch curve on a rhombus shaped fractal patch having compact dimensions of 60 mmx50 mmx1.6 mm with defected ground structure. The reflection coefficient (S11) values of the proposed antenna are-11.97 dB,-20.29 dB, -25.38 dB,-13.91 dB and-23.48 dB at resonating frequencies of 2.8649 GHz, 6.3514 GHz, 7.1622 GHz, 8.2973 GHz, and 8.9459 GHz, respectively. It has values of VSWR at all resonating frequencies within acceptable range of 1 to 2. The prototype of the proposed structure has been designed on easily available and low cost FR4 epoxy substrate material. The bandwidths of 1.39 GHz, 3.30 GHz, 10.19 GHz, 1.93 GHz and 2.23 GHz has been obtained at all resonating frequencies. The measured results has been analyzed and compared with simulated results and bears a close approximation. The developed prototype can be utilized for applications in S, C, and X frequency band which can further be used for various communication applications like radar, satellite communication and wireless computer networks.