An Enhanced Octagonal Microstrip Patch Antenna Circularly Polarized for WIMAX and 5G Mid-Band Applications

In this paper, we present a new octagonal circularly polarized (CP) patch antenna that is suitable for applications such as WIMAX and 5G mid-band. We use a simple and efficient single-port excitation technique to achieve the desired result. The suggested antenna is printed on a Rogers RT/Duroid 5880 substrate with a 2.2 relative permittivity and a low loss tangent (0.0009). Its optimum dimension is 32 × 35 × 1.67 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>. The square slot and stubs in the ground plane are utilized for generating circularly polarized radiation in the ground plane. The obtained bandwidth at -10 dB is from 2.87 GHz to 4 GHz (32.89%), and the axial ratio (AR) below 3 dB is within 3.31-3.69 GHz bandwidth (10.64%). All the obtained results are simulated using the tools (CST) and (HFSS). Our antenna has a compact size and is easy to construct; it has good performance, like a wide band in terms of a reflection coefficient equal to 1.13 GHz; and it is very adequate for mobile applications due to circular polarization, especially for WIMAX and 5G mid-band. This characteristic gives us more freedom to make it in any location.