Compact and Flexible Novel Wideband Flower-Shaped CPW-Fed Antennas for High Data Wireless Applications

Abstract

This communication presents two compact and flexible flower-shaped coplanar waveguide (CPW)-fed antennas (Antenna-1 and Antenna-2) for high data wireless applications. The radiators of the proposed antennas are backed by a flexible and biocompatible polyamide substrate (epsilon(r) = 4.3 and tan delta = 0.004) with 0.025 mm thickness. The flower-shaped radiators of both antennas are designed by introducing rounded slots in the basic circular shape and attaching two branches with the 50 Omega microstrip line. Antenna-1 provides resonance in the 3.5 GHz WiMAX band with a total bandwidth and gain of 484 MHz (3.3-3.784 GHz) and 1.88 dBi, respectively. Antenna-2 is designed by embedding a parasitic element at the back of the substrate of Antenna-1, which leads to significant improvement in the bandwidth. Antenna-2 can also be employed in flexible devices for dual-band operation by proper adjustment of its parasitic element radius and position. A prototype of Antenna-2 is fabricated, and measurements are conducted in the flat as well as in the concave and convex bent configurations for the characterization of its flexibility. It is observed that bending has no prominent effects on the overall performance, except a small shift in the operating frequencies. The proposed flower-shaped antennas are not only visually attractive but also show salient performance. Due to the low cost, visual attraction, compact size, wide bandwidth, and easy integration, the proposed antennas may be used in high data wireless applications as external antennas.