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This paper presents design, fabrication, and testing of a palm tree structured monopole antenna for wideband applications. The proposed antenna has a wide impedance bandwidth (−10 dB bandwidth) from 4 to 10.4 GHz. Palm tree antenna of compact size 23 mm × 20 mm is designed and fabricated on an FR4 substrate of thickness 1.6 mm. To validate the design, a mathematical relationship between the parameters of the palm tree geometry and the lower cut-off frequency has been established. Parametric study has been carried out to obtain optimum wideband characteristics. The prototype is experimentally validated for the band 4–10.4 GHz within ultra-wideband operations. Transfer function, impulse response and Group delay has been plotted in order to address the time domain characteristics of the palm tree antenna with fidelity factor values. The possible applications cover 5.2–5.8 GHz WLAN, C-band operations, 5.5 GHz WiMAX, and Wireless USB.

A new approach to obtain frequency and pattern reconflguration in Dielectric Resonator Antenna (DRA) has been proposed. The design consists of two identical aperture coupled DRAs separated by a distance of ‚0. A switchable feed based frequency reconflguration is discussed in which the feed acts as an ideal switch. This design operates at two frequencies viz., 3.6GHz and 5.2GHz. These frequencies are independently tuned using trimmers. Further, the slot length of both the DRAs can be tuned independently using movable shorting pins driven by miniature motors. The shorting pins form a part of the ground plane. By varying the slot length of the DRA, the resonant frequency is controlled which in turn helps in gaining pattern reconflguration. The structure has been designed for lower and middle band frequencies of WLAN, operating between 5.15{ 5.25GHz and 5.25{5.35GHz, respectively. These types of antennas can be employed in MIMO systems for increasing the capacity through Pattern diversity.