Staked T Lines Integrated Circular Microstrip Tri-band Wearable Antenna for GSM, ISM and NATO Applications

Abstract

Antenna designed with fabrics as dielectric substrate find applications in health monitoring systems, fire-fighting, rescue operations, space, navigation and military personal communications. The aim of this paper is to design a flexible, microstrip antennas that will be mechanically robust and light weight. This type of antenna will find applications in Global System for Mobile communication (GSM), Wireless Fidelity (Wi-Fi) and North Atlantic Treaty Organization (NATO) bands. A tri – band microstrip antenna is designed and constructed with woolen felt as substrate. The dielectric constant of woolen substrate is 1.45, The thickness of the substrate is 1.588 mm. The gain and axial ratio are stable when bent and in presence of moisture. Also the operating band is compliant with specifications. The operating frequencies are 1800MHz (GSM), 3.5GHz (Wi-Fi) and 4-5GHz (NATO). The simulated result of S11 is measured as for all three bands are -13.399dB, -35.114dB and -36.254dB respectively. The tri-band wearable antenna is verified and validated using network analyzer. The testing of triband antenna also involves the calculation of Specific Absorption Rate (SAR) under the standards of IEEE and ICNIRP. The antennas with fabric as substrate allow hands free operation, comfortable and are also economically feasible.