## 2 Material and Method  
### Materials  
In this study, Esun PLA Plus Filament (Filament, esun, Shenzhen, China) was preferred for the substrate material of the antenna due to its high surface quality, high layer structure, and ten times more durability than standard PLA filaments. Detailed information on Physical and Print performances is given in Table 1.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**Physical Performance Properties**} & \multicolumn{2}{c}{**Print Performance Properties**} \\ \hline Parameters & PLA+ & Parameters & PLA+ \\ Appearance & white & Surface finish & No obvious layering \\ Tensile strength & 63 Mpa & Hole column fitting model & 0.3 mm \\ Elongation at break & 20\% & Hanging model & \textless{}60\({}^{\circ}\) \\ Bending strength & 74 Mpa & Suspension bridge & 50 mm \\ Flexural modulus & 1934 Mpa & - & - \\ Notch impact & 9 & - & - \\ \hline \hline \end{tabular}
\end{table}
Table 1: Physical and print performance properties of Esun PLA+ filament [87].  
Black Magic 3D Conductive Graphene Composite filament is used for the conductive part of the antenna due to its superior conductivity and improved mechanical properties, and its detailed properties are given in Table 2.  
The bow-tie microstrip patch antenna design procedure is given in Figure 1. Computer analysis software is central to this work for the design process, as the researcher must have the appropriate design parameters to start the production process. Simulation software is an essential tool for designing a microstrip patch antenna with bandwidth at the desired resonance frequency and showing band-pass, band-stop, or ultra-wideband characteristics. Otherwise, a new antenna must be produced for every charged parameter of the antenna, and the reflection/transmission be measured. Therefore, this process causes a loss of time and increases the design cost. For this reason, using simulation and design software to obtain the transmission/reflection characteristics and optimize the antenna parameters reduces the cost and saves time. In this study, software named CST Microwave Studio was used for microstrip patch antenna design. Polylactic Acid from Esun (Esun PLA+) with a relative dielectric constant of 2.54 and a loss tangent of 0.015 was chosen as the suitable substrate material for the designed antenna. The dielectric material thickness was determined as 1.70 mm. Graphene PLA from BlackMagic was preferred for the conductive part, and its thickness is also 1.70 mm. A computer code that performs the mathematical calculations of the bow-tie antenna was written using MATLAB software (2019, The Mathworks, Inc., Natick, MA, USA). According to the calculated dimensions, the design of the antenna was carried out with the CST Microwave Studio software (CST Studio Suite 2019, Dassault Systemes, Waltham, MA, USA).  
In this section, the parameters affecting the configurability of the graphene-based antenna are evaluated. The first of the two kinds of parameters are related to the geometric structure of the antenna, and it can be optimized with numerical simulations, while the  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Properties** & \\ \hline Brand & Black Magic 3D \\ Weight & 0.1 \\ Volume resistivity & 0.6 ohm-cm \\ Color & Black \\ Diameter & 1.75 mm \\ Size & 100 g \\ Min/max printing temperature & 220 °C \\ Country & United States \\ \hline \hline \end{tabular}
\end{table}
Table 2: Properties of 3D-conductive graphene composite filament [88].  
Figure 1: The design procedure of bow-tie microstrip patch antenna.  
other is related to the graphene model related to the calculation in the previous section. The study aims to understand the behavior of the graphene-based antenna and contribute to future studies of graphene-based antennas.