## 4 Conclusions  
The microstrip antenna designed and prototyped for the 28/38 GHz frequency bands, tailored for 5G and next-generation communication systems, represents a significant leap forward compared to existing designs in the literature. Initially, the design was simulated without connectors, enabling a focused assessment of the connector's influence on the 5\({}_{11}\) parameters post-integration. The subsequent optimization and parametric analyses played a pivotal role in refining the design, resulting in superior fabrication outcomes.  
This single-element microstrip antenna delivers exceptional performance, with gains of 7.82 dBi at 28 GHz and 8.98 dBi at 38 GHz--surpassing typical antenna performance and approaching that of multi-element arrays.  
The proposed antenna design achieves dual-band operation at 28 GHz and 38 GHz, with realized gain values of 7.82 dBi and 8.98 dBi, respectively. These gains are typical for single-element patch antennas. As observed in both the simulation and the VNA measurements, the remarkably low return loss further emphasizes the antenna's excellence and distinct advantage over prior designs. Furthermore, the antenna achieves outstanding efficiency values of 96.02% at 28 GHz and 95.50% at 38 GHz while maintaining narrowband characteristics with bandwidths of 1.12 GHz and 1.27 GHz at their respective center frequencies.  
The findings of this study reveal that while the proposed antenna achieves satisfactory SLL performance at 38 GHz, the \(-2.2\) dB SLL at 28 GHz remains suboptimal, highlighting a need for improvement. Future research will focus on enhancing SLL performance at 28 GHz through advanced optimization techniques to achieve better sidelobe suppression and improve the antenna's efficiency for high-performance 5G applications.  
This study underscores the critical importance of optimization and parametric analysis in the development of high-performance microstrip antennas. This study highlights how a well-optimized single-element design can achieve both high gain and efficiency, demonstrating that smaller configurations can compete with more complex multi-element designs. The impact of the connector on antenna performance has been meticulously examined, providing valuable insights into how connector integration affects S\({}_{11}\) and overall performance. The results further illustrate how the antenna dimensions influence S\({}_{11}\), particularly through the parametric analysis, revealing the key design considerations for achieving optimal performance.  
Conceptualization, B.O.I. and C.K.; methodology, B.O.I. and C.K.; software, B.O.I. and C.K.; validation, B.O.I. and C.K.; formal analysis, B.O.I. and C.K.; investigation, C.K.; resources, B.O.I. and C.K.; data curation, B.O.I. and C.K.; writing--original draft preparation, B.O.I. and C.K.; writing--review and editing, B.O.I. and C.K.; visualization, C.K.; supervision, C.K. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The data that support the findings of this study are available from the corresponding author upon reasonable request.  
The authors declare that they have no competing financial interests that could affect this research.  
The following abbreviations are used in this manuscript: