Performance Enhancement of a Compact Tri-Band Microstrip Rectangular Patch Antenna for 5G Applications

This paper presents a high-performance tri-band Microstrip Rectangular Patch Antenna (MRPA) designed for Fifth Generation (5G) applications. The design addresses the inherent limitations of conventional microstrip antennas, particularly their low gain and narrow bandwidth, while retaining a compact and lightweight structure. The antennas were designed and simulated in Computer Simulation Technology (CST) Studio Suite using a Rogers RT5880 substrate with a thickness of 0.508 mm³, a relative permittivity of 2.2, and a loss tangent of 0.0009. To enhance performance, an I-shaped slot was strategically introduced in the patch between inverted T-slots, and Complementary Split Ring Resonators (CSRRs) were embedded in the Defected Ground Plane (DGP). This integration resulted in a 25% reduction in antenna size, alongside improvements in bandwidth. The reference MRPA with DGP and slots resonated at 10.08 GHz, 28.40 GHz, and 38.20 GHz, achieving bandwidths of 0.23 GHz, 0.74 GHz, and 1.97 GHz with gains of 6.32 dB, 9.08 dB, and 9.68 dB, respectively. After implementing the proposed modifications, the antenna resonated at 10.12 GHz, 28.72 GHz, and 38.20 GHz, with bandwidths increased to 0.25 GHz, 0.76 GHz, and 3.63 GHz (enhancements of 9%, 3%, and 84%), corresponding to gains of 6.45 dB, 9.21 dB, and 8.89 dB. A maximum radiation efficiency of 95% was recorded at 38.20 GHz in both antennas. These results demonstrate that the proposed DGP-Slotted and CSRR-loaded MRPA antenna significantly reduces size and increases bandwidth, making it a suitable choice for compact 5G wireless communication devices.