The development of sustainable and resilient networking and communication technologies, artificial intelligence, dispersed computing, and beyond 5G are expected to play a crucial role in the realization of Industry 5.0. More specifically, antennas are recognized as a vital technology to support the continuously growing demand for 5G/6G connectivity and data rates. In the development of wireless communication systems, an effective antenna design is critical. In this work, we present the design and modeling of a hexagonal microstrip antenna for using in ultra-wide band applications such as 5G mobile networks. The suggested antenna has a frequency range of 3.3 GHz to 4.5 GHz, dimensions of 20 mm × 14 mm, and is built on a FR-4 substrate, with a relative permittivity of 4.3, and of 1.6 mm in height. It is expected that this antenna will operate in two notched bands with resonance frequencies of 3.3 GHz and 4.5 GHz and a voltage standing wave ratio (VSWR) of less than 2. The proposed antenna, which has been expanded to be a multiple-input multiple-output (MIMO) antenna, was created and modeled using CST Microwave Studio. The comparison against the recent works is given to show the efficiency of the proposed design.