No abstract

A planarprinted multiband microstrip fed antenna with reconfigurable frequency performance was designed for multistandard wireless communication systems. The antenna consists on a square shaped patch with an optimized centered Koch‐Island fractal slot. The antenna allows a reconfigurability of the frequency bands by incorporating 16 PIN diodes inside the fractal slot which is highly complex. That is why short and open circuits will be used to produce frequency agility instead of RF switches (for proof of the concept). The proposed antenna is capable to switch between 15 operating frequency bands centered at 1.7, 1.77, 2.36, 2.43, 3.30, 3.61, 3.67, 3.79, 4.05, 4.34, 4.59, 5.2, 5.27, 5.47, and 5.57 GHz through four operating modes M1–M4 over the wide range 1–6 GHz. Prototypes corresponding to different modes were manufactured and characterized. Simulated and measured results are presented and discussed. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:207–212, 2015

A planar printed dipole antenna with reflectors and directors, able to steer its radiation pattern in different directions, is proposed for telecommunication applications. Starting from a dual-beam printed dipole antenna achieved by combining two elementary dipoles back to back, and by loading four PIN diodes, three modes of reconfigurable radiation patterns are achieved at the frequency 2.56 GHz thanks to switches states. A prototype of the structure was realized and characterized; an efficiency of 75% is obtained. Simulation and measured results of the results are presented and discussed.

In this paper, we investigate a new printed antenna based on the 2D image of a fractal tree-leaf geometry by studying the effect of the irregular boundary of the proposed antenna on its radiation characteristics. Both the impedance matching properties and the radiation patterns of the antenna are studied over the frequency band 1-6 GHz. Four configurations are designed by increasing the complexity of the structure, which ranges from iteration 0 to iteration 3. The fractal properties of the proposed tree-leaf antenna are then compared to those of a conventional fractal antenna with smooth edges. Following this, the proposed antennas are fabricated and characterized experimentally. Finally, results are analyzed and discussed, and a practical application for this new type of antennas is proposed.