Comparative Study of Slotless and Slotted Feedline Microstrip Patch Antennas for Multiband Millimetre-Wave Operation

Abstract

Modern communication systems, such as fifth-generation (5G) networks, require antennas with a simple structure, lightweight, and high gain to achieve efficient performance. However, designing compact and effective antennas capable of working in the millimeter-wave (mmWave) band with multiband capability remains a challenge.  This paper presents the design and simulation of two ultra-compact rectangular microstrip patch antennas with feedline transmission, fabricated on a compact Rogers RT5880 (lossy) substrate with a small size (1.52 mm×2 mm). The first design (RMSPA-I) is a traditional rectangular patch antenna without a slot, while the second (RMSPA-II) is incorporates an H-shaped slot on the patch plane and a slot on the ground plane to improve performance. Both designs achieve multiband operation, with RMSPA-I resonating at (2.3GHz and 95.3GHz), and RMSPA-II resonating at (2.3GHz, 73.5GHz, and 88.5GHz). The proposed designs demonstrate improved gain, VSWR, and return loss compared to existing works, while maintaining ultra-compact dimensions suitable for modern mmWave communication systems, including 5G and beyond.