Design and Electromagnetic Analysis of a Triple-Ring Microstrip Patch Antenna for 2.4 GHz ISM Applications

Abstract

Abstract- This Paper presents the development and electromagnetic analysis of a compact rectangular microstrip patch antenna designed to operate in the 2.4 GHz ISM band. The antenna is fabricated on an FR-4 substrate and incorporates a triple-ring resonator arrangement to enhance bandwidth and field interaction. Full-wave simulations carried out in CST Studio Suite confirm a well-defined resonance at 2.401 GHz with a return loss of −27.12 dB and a VSWR close to 1.2, indicating strong impedance matching to a 50 Ω input. The proposed configuration provides an operational bandwidth of nearly 100 MHz and supports multiple resonant modes due to the coupling between ring elements. The antenna achieves a peak directivity of 6.11 dBi in the E-plane, while the H-plane pattern exhibits near-omnidirectional characteristics, making it suitable for short-range wireless links. Near-field electric, magnetic, and surface-current distributions validate efficient radiation and multi-mode operation. Owing to its planar geometry, low cost, and reliable performance, the antenna is well suited for Wi-Fi, Bluetooth, Zigbee, and other 2.4 GHz wireless communication applications.