Automation of Printed MIMO Antenna Design Using MATLAB for 5G Applications

A 4-port multiple input multiple output (MIMO) design using printed Yagi-Uda antennas is proposed for 5G applications. The proposed design consists of 4 printed Yagi-Uda antennas at four corners of an FR4 substrate. A script has been written in MATLAB for designing the antenna in CST Microwave Studio. When the code is run in MATLAB, it automatically opens up CST using an API and draws the antenna in CST as per the dimensions given in the code. Two poles of different lengths have been used to form the dipole element (driven element) of each antenna. An isolator patch has also been designed and used midway on the substrate to yield better isolation. The overall dimension (125mm $\times 200$ mm $\times 1.6$ mm) of the proposed structure is almost similar to the dimension of a Tab. Hence it can be used inside gadgets like Tab or Laptop. This design is capable of operating in two 5G bands – n3 (1.71-1.78 GHz) and n78 (3.3-3.8 GHz). The simulated and measured results are in good agreement and they show decent isolation (cross-port S-parameters <−20 dB). Simulated gain-values obtained in both the bands are also decent $(\sim 1$ dBi at n3 and $\sim 4$ dBi at n78).