A new type of compact ultra‐wideband planar fractal antenna with WLAN band rejection

Abstract

Abstract A new type of fractal‐shaped microstrip patch antenna for ultra‐wideband (UWB) applications and with sufficient rejection in the WLAN band is presented. The radiating patch is placed on a 1.6 mm thick low‐cost FR‐4 epoxy substrate and is fed using a symmetric coplanar waveguide. The size of the proposed antenna in terms of wavelength is 0.189 λ 0 × 0.197 λ 0 . A sectorial‐circular slot in the patch is used to create WLAN band notch. An impedance bandwidth of 11.76 GHz (from 2.19 to 13.95 GHz) is achieved, along with achieving WLAN band rejection from 4.67 to 6.21 GHz. Nearly omnidirectional radiation pattern with the maximum gain of 5 dB in the passband is achieved. In the rejection band, the gain drops to −3 dB. The simulated results are verified against experimental data and a good agreement between the two sets of data is seen. The proposed antenna covers both the unlicensed 2.4 GHz band and the UWB.