Belen, AysuGüneş, FilizBelen, Mehmet AliMahouti, Peyman2020-05-202020-05-202020Belen, A., Güneş, F., Belen, M. A., & Mahouti, P. (2020). 3D printed wideband flat gain multilayer nonuniform reflectarray antenna for X‐band applications. International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, 33(6), doi:10.1002/jnm.2753.https://hdl.handle.net/11494/2066Reflectarray antenna designs have become an efficient solution alternative totheir counterpart designs due to their beam scanning capability, low profile, highgain, and mounting flexibility. Herein, design and realization of a wideband, flatgain multi-layer nonuniform reflectarray (MNURA) using 3D printing technologyis presented. Design optimization of the proposed MNURA has been achieved inthe two stages: First, a 3D CST Microwave Studio based Multilayer PerceptronNeural Network (MLP NN) model establishes the reflection phase characteristicof the MNURA unit element as an accurate continuous function of the geometri-cal design parameters and dielectric constant. Then Differential EvolutionaryAlgorithm DEA is selected as a powerful optimization algorithm for determiningthe optimum geometrical design parameters and dielectric constant of MNURAthroughout the X-band to have a large range, wideband, and flat gain RA design.3D printing technology has been used for prototyping of the proposed MNURAdesign. Here, the resulted optimum dielectric constant value of 2.2 is realized by56% infill rate of“Polar White”PLA using the relation between the infill rate anddielectric constant. The prototyped antenna has a total size of 300×300 (mm),and its measured performance characteristics achieve a wideband flat gain of23.2 dBi with a ripple level of almost 1.5 dBi and return loss characteristic of lessthan?10 dB over the operation band of 8 to 12 GHz.eninfo:eu-repo/semantics/closedAccess3D printerFlat gainMultilayer perceptron neural networkReflectarray idebandX-bandArticle33610.1002/jnm.2753Q2Q4