A novel compact fractal UWB antenna with dual band notched characteristics

A very compact dual band notched fractal structured antenna is proposed for UWB applications. A novel fractal patch with defected ground structure is utilized to achieve −10 dB bandwidth of 7.87 GHz from 3.77 GHz to 11.64 GHz. To notch upper WLAN band of 5.52–5.90 GHz, an S- shaped slot is introduced in the 50 Ω microstrip feed line. The X- band notch for down link of satellite communication applications from 7.22–8.16 GHz is achieved by two symmetrical L- structured parasitics on both sides of fractal patch. The proposed antenna having a compact size of 16 × 21 mm 2 ( 0.2 λ 0 × 0.26 λ 0 ) and is fabricated on a low cost FR- 4 substrate. A maximum gain of 4.32 dBi in UWB band with gain drops to −2.53 dBi in WLAN at 5.75 GHz and −4.25 dBi in X-band at 7.35 GHz are noticed. The proposed antenna shows good similarity between simulated and measured electrical parameters such as S 11 , nearly omnidirectional patterns, constant gain and time domain characteristics makes it suitable for portable wireless applications.