A Microstrip Antenna Using I-Shaped Metamaterial Superstrate with Enhanced Gain for Multiband Wireless Systems

This paper presents the design of a rectangular microstrip patch antenna (MPA) using the I-shaped metamaterial (MTM) superstrate. A seven × seven array of the I-shaped MTM unit cell is used as the superstrate to enhance the antenna performance. The antenna is fed by a microstrip feeding technique and a $50 \mathsf{\Omega }$ coaxial connector. An in-phase electric field area is created on the top layer of the superstrate to improve the performance of the antenna. The proposed I-shaped MTM-based rectangular MPA produces three operating frequencies at 6.18 GHz, 9.65 GHz, and 11.45 GHz. The gain values of the proposed antenna at 6.18 GHz, 9.65 GHz and 11.45 GHz are 4.19 dBi, 2.4 dBi, and 5.68 dBi, respectively. The obtained bandwidth at frequencies 6.18 GHz, 9.65 GHz and 11.45 GHz are 240 MHz (3.88%), 850 MHz (8.8%), and 1010 MHz (8.82%), respectively. The design and simulation of the antenna are done using the Computer Simulation Technology (CST) studio suite and MATLAB. The proposed I-shaped MTM-based rectangular MPA is fabricated on a low-cost FR-4 substrate and measured using the Agilent 8719ET network analyzer. The proposed antenna has an overall dimension of 70 × 70 × 1.6 mm³. A significant improvement in the gain of the antenna up to 74.28% is achieved. The obtained results confirm that the proposed multiband antenna has a high gain, and enhancement in bandwidth and radiation efficiency. These properties make the proposed antenna suitable for the multiband wireless communications systems such as Wi-Fi devices, radar systems, short- and long-range tracking systems, etc.