A Novel High-Gain Microstrip Patch Antenna Loaded with Patch Slots and Defected Ground Structure for GNSS Applications

This paper introduces a novel microstrip patch antenna designed for Global Navigation Satellite Systems (GNSS) applications. The antenna operates at 1.225 GHz and effectively covers key GNSS frequency bands, including GPS (L2, L5), Galileo (E5, E6), and GLONASS (L2, L3, L5). The proposed antenna is developed on an FR-4 substrate with compact dimensions of $90 \times 70 \times 1.8 \text{mm}^{3}$. It incorporates a slotted radiating patch along with a defected ground structure (DGS), which together significantly improve gain and bandwidth across the targeted GNSS frequency bands compared to the recent works. The proposed antenna exhibits a return loss of -37 dB and VSWR of 1.028 at 1.225 GHz, with a bandwidth of 18.2 %, covering all of the above-mentioned bands. Moreover, it achieves a gain exceeding 8.3 dB and directivity over 9 dB across all bands with an efficiency of over 90 %, which is a significant contribution of this work. It offers an impedance of approximately 50Ω, indicating excellent impedance matching, with a surface current reaching upto $26.6 \mathrm{A} / \mathrm{m}$. CST Microwave Studio has been utilized to design and analyze the antenna performance parameters for this research.