Performance of wearable circularly polarized antenna on different high frequency substrates for dual-band wireless applications

Abstract

This paper proposes the effect of different dielectric constants to construct a microstrip patch antenna deployed on Jean's textile covering military wireless applications. Initially, the structure is designed with double L-shaped slits inserted on both sides of the patch with an FR4 dielectric constant of 4.4. Antenna dimensions are 40 ? 25 mm2, which is miniature compared to the wave's length (?) at the desired operating frequency. The proposed antenna performance in terms of simulated parameters such as gain in dBi, reflection loss (S11), directivity, and patch antenna radiation efficiency are executed by the CST MW EM simulator. However, the conventional way of this design with FR4 may not be so reliable when it is designed on Jean's substrate. Besides all the above parameters extracted from the simulator should hold a low value to implement a high-performance deployed wearable antenna. The paper's outcome shows the importance of simulations and measurements undertaken for the proposed antenna assuming both the dielectric constants of FR4 and Jeans cloth material (with ?r of 1.7). The main contribution of the antenna is to resonate at the frequencies of 3.17 GHz with circular polarization and 5.04 GHz with linear polarization. The antenna prototype is described, and its performance is validated using measurements. The proposed structure also provides a better enhancement in terms of 10-dB impedance bandwidth, with an average gain of 5 dBi.