This paper proposes the design and implementation of a circular triangle fractal antenna for portable ultra-wideband (UWB) communication applications with band rejection at WLAN band. The presented antenna is made with iterative generation of a circular triangle shaped elements arranged in circular fashion with self-similarity and periodicity property with coplanar waveguide feed. The overall dimensions of the antenna are 28× 27 x 1.6 mm3. The fractal resonating plane and ground plane dimensions of the proposed antenna are optimized to obtain a resonance bandwidth of 2.39-12.28 GHz which corresponds to fractional bandwidth of 134.8% with notch band from 5.45 to 6.27 GHz to mitigate the problem of interference from WLAN. The peak gain detected is 11.16 dBi. The proposed prototype was fabricated on a 1.6 mm thick FR4 material with the relative permittivity of 4.4, and the sample was tested. The experimental results are in close agreement with the simulated ones. The time domain analysis indicates that the proposed antenna is not dispersive. The antenna radiates in a virtually omnidirectional pattern. Due to these merits, this proposed antenna can be used in UWB applications.
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