Design of Frequency Reconfigurable Antenna with Split Ring Resonator and Diode Control for Omnidirectional Applications

Abstract

This paper presents a novel antenna design featuring frequency reconfiguration through the use of a diode. The antenna incorporates curved slots on the patch and a central circular-shaped split ring resonator, achieving dual-band operation. When the diode is ON, the antenna operates at 5.5 GHz and 7.1 GHz, and when the diode is OFF, it operates at 6.7 GHz and 7.6 GHz. The VSWR remains below 2 in both states, indicating efficient impedance matching. Additionally, the antenna maintains an omnidirectional radiation pattern regardless of the diode state, ensuring uniform signal distribution. The design employs a low-cost FR4 epoxy substrate and microstrip line feeding, balancing affordability and performance. This reconfigurable antenna is suitable for applications requiring flexible frequency tuning and reliable signal coverage.