Study and Design of Printed Rectangular Microstrip Antenna Arrays at an Operating Frequency of 27.5 GHz for 5G Applications

In this paper, the authors studied and designed a simple patch antenna with a rectangular shape and exploited it to construct an array formed by two antennas in parallel and another one formed by four antennas in parallel in the 5G millimeter band with an operating frequency of 27.5 GHz. This study aims to obtain better antenna performances like gain, directivity, S11, bandwidth, and efficiency. In this paper, we use a polyamide-type substrate with relative permittivity εr of constant value equal to 4.3, thickness hs of constant value equal to 0.15 mm, width Wg  3.77 mm and length Lg  4.55 mm, which represents a suitable material for antenna designs proposed in this paper. Furthermore, in this paper, the total size of this single printed antenna is equal to 2.578  3.35  0.15 mm3. The single patch antenna resonates at 27.0787 GHz with a return loss (S11) measurement value equal to – 28.1548 dB, a bandwidth value equal to 1.03 GHz, a VSWR of 1.081, a gain value equal to 6.3 dB, a directivity value equal to 6.7 dB, and radiation efficiency of 92.64 %. The proposed 1  1 antenna array operates at 27.42 GHz and improves the performance achieved with a previous single antenna as follows, including S11 (down to – 30 dB), gain (7.3 dB), and directivity (7.8 dB). Similarly, the proposed 2  2 antenna array successfully improves S11 down to – 31.7 dB, gain up to 10.6 dB, bandwidth up to 1.07 GHz, and directivity up to 11.2 dB at a resonant frequency of 27.078 GHz. The antenna designs presented in this paper are performed using the high-frequency structure simulation (HFSS) tool. In addition, antennas proposed in this paper are adapted to the 27.5 GHz frequency range as well as applied to the 5G mobile communication system.