Optimized Design of Antennas based on U-Shaped Slots for Wireless Connectivity

This article presents the design and analysis of a “U” slot patch antenna realized on a FR4 substrate, for dual band operation at frequencies of 2.5 GHz and 3.5 GHz. The antenna achieves a reflection coefficient (S11) of -17 dB at 2.5 GHz with a gain of 2.75 dB, and of -15 dB at 3.5 GHz with a gain of 1.55 dB. The integration of “U” slots improves impedance adaptation and allows miniaturization while maintaining acceptable performances. The low-cost use of FR4 substrate makes this design suitable for applications requiring compact and economical solutions, such as wireless communications and IoT devices. The simulation results, including S-parameters and radiation diagrams, confirm the antenna's ability to meet the requirements of dual band applications. Prospects for improvement, notably to increase the gain and bandwidth, are also discussed.