Design of a Dual-Band Flexible Microstrip Patch Antenna on Transparent Substrate for IoT and ISM Band Applications

The presented work follows a transparent and flexible dual band microstrip-fed patch antenna that can function in both Internet of Things (IoT) and Industrial, Scientific and Medical (ISM) Band applications. The radiating parts of the antenna consist of two inverted L-shaped patches with two slots cut on it fed by a microstrip feedline along with a rectangular stub above it while the ground plane is modified to achieve dual-band functionality. The novelty of the presented work is showcased by the use of low-cost and flexible Polyethylene terephthalate (PET) material, a thermoplastic semi-crystalline polymer of the polyester group has been used as the substrate with dielectric constant taken as 3.6 and a thickness of 1.6 mm, to achieve optical transparency. The antenna is capable of resonating within the frequency bands of 3.56 GHz to 6.73 GHz with an impedance bandwidth span of 0.26 GHz over frequencies of 3.56 GHz to 3.82 GHz and 1.42 GHz over 5.31 GHz to 6.73 GHz. The proposed design of the antenna is simulated using the Ansys HFSS (High Frequency Structure Simulator) software which runs on finite element method (FEM) technique and then finally fabricated.