Modeling and Up-Gradation of Concentric Circular Shaped Patch Antenna to Array Antenna with the Improved Performance for 5G Millimeter- Wave Communication. PJETS [Internet]. 2025 Jul. 30 [cited 2026 May 20];13(1):121-33. Available from: https://journals.iobm.edu.pk/index.php/pjets/article/view/1286