A compact planar microstrip-fed ultra wideband antenna for triple bands is presented and analyzed. The proposed antenna consists of semi-circular shaped radiating patch with two I-shaped stubs. It provides a wide bandwidth of 3.05–11.7 GHz. A pair of spiral loop resonators merges with radiating patch to create the first notched band in 3.3–3.7 GHz for the WiMAX system. In addition, integrated microstrip resonators are coupled with ground to generate the second- and third-notched bands in 5.2–5.4 GHz for lower WLAN and 5.7–6 GHz for upper WLAN, respectively. Experimental results of the proposed antenna exhibit good radiation pattern, stable gain, and consistent group delay performances. The time domain behavior of the antenna with and without resonator is analyzed.
Dr. Natarajamani S., Behera, S. Kumar, and Patra, S. Kumar, “A triple band-notched planar antenna for UWB applications”, Journal of Electromagnetic Waves and Applications, vol. 27, pp. 1178-1186, 2013.