A dual-band flexible antenna incorporated with the fractal structure using coplanar waveguide (CPW) is proposed for 2.42 GHz WLAN and 3.78 GHz WiMAX applications. The antenna is printed on a low-cost FR4 substrate having a thickness of 0.5 mm with overall antenna dimension of 97.48x80 mm2. Incorporation of fractal geometry leads to improvement in terms of impedance bandwidth and radiation efficiency. The simulated and measured results of the proposed antenna in terms of return loss (S11), gain, radiation pattern, and VSWR are presented here which show great correlation. The measured impedance bandwidth and gain of the flexible antenna are 17.08% (2.20 GHz-2.61 GHz), 16.30% (3.38 GHz-3.98 GHz), 4.56 dBi and 1.09 dBi, respectively. The proposed dual-band antenna shows omnidirectional and bidirectional radiation patterns in H and E-planes which makes it suitable for its use in low-cost Bluetooth/WLAN/WPAN/WiMAX applications.
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