Triple-Band Reconfigurable Microstrip Patch Antenna with Asymmetric DGS for L and C Band Applications

This paper presents the design analysis of a reconfigurable triple-band patch antenna with a defected ground structure (DGS) aimed at enhancing antenna performance across multiple frequencies. The antenna parameters, including reflection coefficient and radiation pattern, were simulated using Computer Simulation Technology (CST) microwave software. The designed antenna S11 results indicated operation across multiple frequency bands, spanning from 1.4 GHz to 4.5 GHz. Within this range, three significant frequencies were identified: 1.5 GHz, 3.8 GHz, and 4.4 GHz. At these frequencies, the S11 values were recorded as -28.4 dB, -22.44 dB, and -19.62 dB, respectively demonstrating excellent impedance matching at each band. The incorporation of DGS effectively modifies the current distribution and mitigates electromagnetic interference, contributing to improved bandwidth, gain, and radiation characteristics. Diodes are integrated within the antenna structure to achieve dynamic frequency reconfiguration, enabling the antenna to selectively operate at any of the three specified bands. The study provides simulation and results analysis, illustrating the design's efficacy in achieving significant performance improvements and flexibility in multiband frequency selection.