# Enhancement of Feed Source through Three Dimensional Printing
## 1 Introduction  
At microwave frequency, a horn antenna has wide applications, and is used as a feed element in large antennas, radar communication, and mobile and satellite communication, as a standard antenna to compare it with other antennas [1]. The modern wireless system requires greater bandwidth with efficient data transmission. This requires the system to maintain a greater frequency band with improved channel capacity and wider bandwidth [2, 3]. The gain level of a horn antenna is usually maintained by aperture size and its length. However, higher aperture size results in increased length of the horn. Several studies have been conducted to address this issue, such as structure design across the interior E-plane wall of a pyramidal horn antenna, which is able to decrease side lobe levels and increase the gain of the horn antenna [4]. The growing use of the three-dimensional printing process is used to realize 3D printed horn prototype either through a metal 3D printing process [5, 6] or by using a spray of metal on 3D printed parts [7, 8]. This has resulted in an increase of costs during fabrication. Additionally, studies on meta surfaces are summarized in [9], which shows the flexible capability of microwave metamaterials in the manipulation of electromagnetic waves. It has been widely used in antenna design in recent years due to its planar structure and its potential to enhance antenna performance interms of directivity, gain, and side lobe levels. The printed patches are generally used to realize the subwavelength meta surfaces as studied in [10], maintaining a proper thickness of dielectric plate and gap between nearby patches [11], a series of subwavelength metallic split ring resonators [12], use of multilayer non uniform meta surfaces that are formed by squares and ring metal patches [13], and an ultrathin metasurfaces lens developed to provide transmission phase compensation for a wide flare angle conical horn [14]. However, these metasurfaces have limited adjusting capacity to electromagnetic waves so difficulties arise in the further application of antenna design. In addition, a metal wideband phase correcting structure was proposed in [15] but it shows a higher value in aperture phase distribution and the required defined distance between two metal layers showing a complex geometrical structure. Interestingly, the application of 3D printing is widely used in the microwave field [16]. A dielectric loaded profile conical horn antenna was designed in [17], which uses more dielectric materials to be filled. In order to have a low profile, a light weight and the use of fewer 3D printed materials with a lower side lobe level, a cube structure was considered, as in [18], to show a reduced side lobe level, whereas in [19] the considered structure was able to maintain phase correction for about 40\({}^{\circ}\). The advancement in additive manufacturing technologies is growing in significance in the field of electromagnetic wave propagation; these were studied in [20; 21; 22; 23; 24]. Considering this aspect, the novelty of this manuscript was in proposing a simple, low profile, easily realizable geometrical structure that will be able to have a more uniform phase distribution, which can be further analyzed to study the deviation of the radiated beam direction. Hence, we designed a low profile, light weight, 3D printed horn antenna through Fused Deposition Modeling (FDM) with a double layer of copper throughout its surface, which is fed by a WR-75 waveguide through the bottom part. The five layers of the cube structure generated by the Multijet Printing technique was able to generate a more uniform phase distribution that shall ultimately improve the performance of the feed source. The proposed work shows efficiency in the utilization of the 3D printing technique in realizing the meta surface. The proposed structure, which was realized by a defined cube pattern, and size was helpful for understanding phase uniformity analysis against other literature studies performed in [13; 14; 15; 17].