2.4 GHz Microstrip Patch Antenna Fabricated by Means of Laser Induced Graphitization of a Cellulose-based Paper Substrate

Since its first discovery in 2014, laser-induced graphene (LIG) has gained increasingly attention as a simple and low-cost alternative to printing techniques, which instead require additional materials such as functional ink or adhesive layers. While there are several works on LIG supercapacitors, gas sensors, and triboelectric generators, this method is still very unexplored for antennas, especially if realized on eco-friendly paper substrates. In this paper, we realized a microstrip patch antenna using LIG on a food-derived cellulose-based paper. The antenna was first designed and simulated using a High-Frequency Structure Simulator (HFSS) software, using different values of relative permittivity ϵr (from 2 to 3.6), to understand the impact of laser-induced graphitization of the substrate on the resonance frequency. The subsequently fabricated antenna showed a strong resonance peak of −25dB at 2.4 GHz, corresponding to an ϵr of 2.2, in agreement with experimental results.